TCD-87-F Technical Committee Docu mentation

1987 Fall M e e t i n g

T e c h n i c a l C o m m i t t e e D o c u m e n t a t i o n

TCD-87-F

A Compilation of the Documented Action on Comments Received by the Technical Committees Whose Reports Have Been Published

Prior to Consideration at the NFPA Fall Meeting

Red Lion Inn Portland, Oregon

November 9-12, 1987

Please Bring to the Fall Meeting I

Copyright ~: 1987

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National Fire Protection Association, Inc. Batterymarch Park, Quincy, MA 02269

13M-9-87-TCD Printed m U.S.A.

SUPPLEMENTARY

Report of Committee on Building Construction

Correlating Committee

Donald W, Belles, Chairman Donald W Bel les& Assoc. Inc.

Ron Cote', Secretary National Fire Protection Association

(Nonvoting)

John G. Degenkolb, Carson City, NV Kenneth A. Kander, M&M Protection Consultants Harold E. Nelson, NBS/Ctr. For Fire Research Chester W. Schirmer, Schirmer Engineering Corp. William A. Schmidt, Bowie, MD Edward J. Ward, Factory Mutual Research Corp.

Nonvoting

Jonas L. Horehart, Natl Inst i tu tes of Health Rep. NFPA Safety to Life Committee

Technical Committee on

Smoke Management Systems

Harold E~ Nelson, Chairman Ctr. for Fire Research

Ron Cote', Secretary National Fire Protection Assn.

(Nonvoting)

John A. Antola, American Insurance Services Group Donald W. Belles, Donald W. Belles & Assoc., Inc.

Rep. AAMA David O. Bruce, Smith Hinchman & Grylls Jack B. Buckley, I . A. Naman+ Assoc - Consulting Engineers Thomas C. Campbell, Saratoga, CA

Rep. Thermal Insulation Mfgrs. Assn. Gregory F. DeLuga, MCC Powers Michael Earl Dil lon, Syska & Hennessy S.E. Egesdal, Honeywell, Inc.

Rep. NEMA Gunnar Heskestad, Factory Mutual Research Corp. Vincent J. Hess;on, Bell Communications Research

Rep. NFPA IFPS J. E. Holt, Colt In t l Group Ltd. Neal D. Houghton, Bldg Owners &Mgrs. Assn. I n t l William R. Houser, US Army Environmental Hygiene Agency John Kampmeyer, Maida Engineering Francis J. HcCabe, Prefco Products" Ernest E. Mi l le r , Industr ial Risk Insurers Gregory Mi l le r , Code Consultants Inc. Lyman L. Parks, New Jersey Bell Telephone Co. Zenon A. Pihut, Texas Dept. of Health Alan J. Pinkstaff, St. Louis Cnty. Dept. of Public Works

Rep. BOCA Brad Remp, Clark County, Nevada Bldg. Dept. J. Brooks Semple, Smoke/Fire Risk Mgmt. Inc. Howard H. Summers, Jr . , VA State Fire Marshal

Rep. FMANA George T. Tamura, Natl Research Council Canada James R. Thiel, Underwriters Laboratories Inc. Robert Van Becelaere, Ruskin Manufacturing

Rep. AMCA Thomas E. Waterman, Ins t i t u te for Advanced Safety

Studies W i l l i am A. Webb, Ro l l Jensen & Assoc. Inc .

Alternates

John H. Klote, NBS/Ctr. for Fire Research (Alternate to H. E. Nelson)

Jayendra S. Parikh, Underwriters Laboratories Inc. (Alternate to J. Thiel)

Edward J. Ward, Factory Mutual Research Corp. (Alternate to G. Heskestad)

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This l i s t represents the membership at the time the Committee was balloted on the text of this edit ion. Since that time, changes in the membership may have occurred.

The Supplementary Report of the Committee on Building Construction is presented for adoption.

Thls Supplementary Report was prepared by the Technical Committee on Smoke Management Systems and proposes for adoption a Supplementary Report which documents i ts action on the public comments received on the proposed revision to NFPA 92A-1988, Recommended Practice for Smoke Control Systems, published in the Technical Committee Reports for the 1987 Fall Meeting.

This Supplementary Report has been submitted to l e t te r bal lot of the Technical Committee on Smoke Management Systems which consists of 29 voting members; of whom 22 voted af f i rmat ive ly , 3 negatively (Messrs. Heskestad, Pihut and Thiel), and 4 bal lots were not returned (Messrs. Antola, Bruce, Holt and Waterman).

Mr. Heskestad voted negatively because he strongly disagrees with the Committee's rejection of two key recommendations. Essentially, these were l) to l im i t the document exclusively to buildings with automatic f i r e suppression and 2) to account for f i r e pressures caused by volume expansion. He added that neglect of volume expansion may render a smoke control system useless; especially vulnerable wi l l be designs with re la t i ve ly low return flows from the smoke zone.

Mr. Pihut commented with his negative bal lot that smoke control without control of smoke source ( f i re ) does not constitute a smoke control system.

Mr. Thiel voted negatively because of the Committee Action on Public Comment 92A-95, Paragraph 3-4.3.4. He expanded his explanation with the following:

"Without the proposed revision (Public Comment 92A-95), there is nothing in the performance requirements in this document for dedicated or nondedicated systems that d i f ferent ia tes them from ordinary HVAC systems. Contrary to the Committee Comment, UL believes that a higher level of supervision is required For a l l sa fe ty - to - l i f e systems.

"UL has considered smoke control system performance from the perspective of sa fe t y - to - l i f e , such as described in NFPA 7] and 72-Series Standards. In that l igh t i t is important that the system be able to recognize whether a signal (command) has been properly received; and that the signaling/control channels between equipments be monitored for in tegr i t y . UL believes that monitoring for in tegr i t y of signal path ( instal led wiring) in the conventional sense of monitoring signal transmissions only is impractical and would not insure acceptable operabi l i ty of the smoke control system.

"By requiring end-to-end ver i f i ca t ion of receipt and execution of commands, a Form of dynamic supervision is realized. In order to achieve a minimum acceptable level (frequency) of supervision, the system must re ly on something other than actual smoke control si tuat ions, which are re la t i ve ly infrequent and occur a f ter - the- fac t . For this reason an a~tomatic weekly test for dedicated systems is proposed, given the isolat ion of this kind of system from dai ly usage. Nondedicated systems, on the other hand, are more frequently operated on the course of dai ly use, and system flaws would be more quickly recognized and corrected. The current proposal (paragraph ¢-4.3.1) to require semiannual testing of dedicated systems could adversely af fect the level of r e l i a b i l i t y of system operation. The frequency of system testing can be shown to relate to operational r e l i a b i l i t y - i . e . , i f corrective actions and maintenance are carried out, weekly testing can introduce higher performance r e l i a b i l i t y than semiannual test ing."

Although not reflected in the above bal lot statement, Mr. Heskestad's alternate, Edward Ward, also submitted a negative bal lot because he disagrees with the Committee Action of rejecting multiple recommendations to l imi t i ts application to buildings equipped with automatic sprinklers or other SUppression systems.

The Supplementary Report has also been submitted to l e t t e r bal lot of the Correlating Committee on Building Construction, which consists of 7 voting members; a l l of whom voted af f i rmat ive ly .

(Log #3) 92A - l - (Entire Document): Reject SUBMITTER: Rick R. Schartel, Wyomissing H i l l s , PA COMMENT ON PROPOSAL NO.: 92A-I RECOMMENDATION: Return entire document to Committee for Further Study. SUBSTANTIATION: Smoke control systems without benefit of automatic suppression may be overwhelmed by a serious f i r e condition. I support the negative votes of Messrs. Heskestad and Pihut. COMMITTEE ACTION: Reject. COMMITTEE COMMENT: The automatic sprinkler question has been addressed in the Committee Action on Comment 92A-7 (Log #17) and Comment 92A-8 (Log #I08).

(Log #90) 92A - 2 - (Entire Document): Reject SVBMITTER: Edward J. Ward, Factory Mutual Research Corp. COMMENT ON PROPOSAL NO.: 92A-I RECOMMENDATION: I f my f i r s t two comments on Sections I - I and l-2 are not incorporated, the entire document should be returned to the Committee for reconsideration. SUBSTANTIATION: I f this document is intended for use at unsprinklered buildings i ts design guidance is minimal or inadequate. I t refers to ASHRAE as the principle reference, is limited to low cei l ing heights and pressure differences are insuf f ic ient . COMMITTEE ACTION: Reject. COMMITTEE COMMENT: The automatic sprinkler question has been addressed in the Committee Action on Comment 92A-7 (Log #17) and Comment 92A-8 (Log #I08).

(Log #137) 92A - 3 - (Entire Document): Reject SVBMITTER: C.V. Lovett, Easton, CT COMMENT ON PROPOSAL NO.: 92A-I RECOMMENDATION: Return this document to Committee for Further Study. SUBSTANTIATION: This document has taken many false assumptions. I t only applies to a specific type of building but is recommended for a l l types, sizes, etc. buildings. COMMITTEE ACTION: Reject. COMMITTEE COMMENT: None of the so-called "false assumptions" are identi f ied by the Commenter.

(Log #143) 92A - 4 - (Entire Document): Accept SVBMITTER: John H. Klote, National Bureau of Standards COMMENT ON PROPOSAL NO.: 92A-I RECOMMENDATION: Change the term "pressure d i f fe ren t ia l " to "pressure difference" throughout 92A. SUBSTANTIATION: Both terms are used in the text, but the term "pressure difference" has the proper meaning in this context. The other term would be appropriate for an analysis using d i f fe rent ia l equations. COMMITTEE ACTION: Accept.

(Log #16) 92A - 5 - (Entire Document): Accept in Part SVBMITTER: Neal D. Houghton, BOMA COMMENT ON PROPOSAL NO.: 92A-I RECOMMENDATION: Delete a l l references to "Areas of Refuge".

Section I - I , second paragraph, third l ine, delete the words, "Areas of Refuge".

Section I-4, fourth paragraph, "Refuge Area" delete entire paragraph.

Section 2-1.4, "Refuge Areas" delete entire section. SUBSTANTIATION: I t is a travesty to suggest that a safe waiting area can be created on a f i r e f loor , par t icular ly in a nonsprinklered building. Section 2-1.4, Refuge Areas, states that " . . . . design c r i t e r i a have yet to be developed"; but the implication is that, in spite of this caveat, the 92A document provides such c r i te r ia . Such inconsistency casts doubt upon the whole document.

COMMITTEE ACTION: Accept in Part. AS suggested by the Commenter, in I-1, second

paragraph, third l ine, delete the words "areas of refuge" and in I-4, Definitions, delete, in ent i rety, the def in i t ion of "Refuge Area".

Revise 2-1.4 by changing wording, deleting portions, and combining the two paragraphs so as to read:

2-1.4 Tenable Environment. A nonsmoke zone of a zoned smoke control system may be used as an area intended to protect occupants for the period of time needed for evacuation. The concept of area of tenable environment in which building occupants could wait out large f i res has not achieved wide acceptance and design c r i t e r i a have yet to be developed. COMMITTEE COMMENT: The Commenter's f i r s t two recommendations have been accepted by the above Committee Action. The third, dealing with 2-I.4, was rejected because the concept of an area of "tenable environment" (vs area of refuge) is important to describe as a barr ier which maintains a tenable environment For the period of time necessary for evacuation. The sentence describing the problems of "waiting out" a f i r e actually explains the Commenter's argument and should be retained as modified above.

(Log #41) 92A - 6 - ( l - l ) : Accept SVBMITTER: Gregory F. DeLuga, MCC Powers COMMENT ON PROPOSAL NO.: 92A-1 RECOMMENDATION: Rearrange text as follows:

Remove the last sentence from paragraph l - l : Detailed Engineering Design Information is contained

in the ASHRAE publication, "Design of Smoke Control Systems for Buildings".

Add the above sentence to the end of paragraph I-6.1, since the subject of design c r i te r ia is introduced in paragraph I-6.1. SUBSTANTIATION: Paragraph l - I does not address specific smoke control design c r i te r ia , thus the referenced sentence is more appropriately placed as indicated above. COMMITTEE ACTIOn: Accept.

(Log #17) 92A - 7 - ( I - I ) : Reject SUBMITTER: Gunnar Heskestad, Factory Mutual Research Corp. COMMENT ON PROPOSAL NO.: 92A-I RECOMMENDATION: Change sentence beginning "In general, l imit ing . . . . " to:

"Limiting f i r e size by provision of automatic sprinklers or other means of automatic suppression w i l l be necessary for ef fect ive control of smoke." SUBSTANTIATION: Without automatic suppression, a f i r e w i l l often go into a flashover phase with pressure differences across smoke barriers easily exceeding the minimum recommended values. COMMITTEE ACTION: Reject. COMMITTEE COMMENT: Automatic suppression w i l l , in most situations, be necessary for ef fect ive control of smoke. Given that the proposed document could apply to numerous occupancy types, means other than automatic extinguishment, such as separation of combustibles, can be used as part of an ef fect ive smoke control system.

(Log #108) 92A - 8 - ( I - I ) : Accept in Principle SUBMITTER: Elmer Chapman, Levittown, NY COMMENT ON PROPOSAL NO.: 92A-I RECOMMENDATION: In l - l , de f in i t i ve ly state that automatic sprinkler protection is necessary for successful smoke control. SUBSTANTIATION: The size of the f i r e and the quantity of smoke to be controlled is not stated in this draft of 92A. The size of a f i r e and the quantity of smoke must be limited. A zoned smoke control system can not be designed to handle unlimited volumes of smoke. Smoke volume must be limited by l imit ing Fire size. An engineered system must be designed to meet predetermined specifications. Designers of a bridge

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must know the maximum weight the bridge is expected to carry. The bridge is then designed to this specif ication plus a safety factor. When the engineer calculates the design of a building he must determine the Floor loading and then design to meet this specif ication. I t cannot be for an unspecified load. When designing a zoned smoke control system, the amount of smoke expected to be handled by this system must f i r s t be determined and the system then designed to meet this specification. I t cannot be for an unspecified amount. Butcher and Parnell stated in thei r book "Smoke Control in Fire Safety Design" on page 6:

" I -4 Limiting the f i r e size for the purpose of design calculation: In the general case of a developing f i r e in a building, the calculation of smoke quantities becomes almost impossible because conditions are changing in a way which cannot usually be predicted. I t has been shown that the rate of smoke production depends on the size ( i . e . , the perimeter) of the f i r e , so that as a Fire grows and i ts boundaries spread, the rate of production w i l l also increase. On the other hand, the rate of smoke production also depends upon the height of clear space above the Fire. As the f i r e develops, the smoke layer collecting beneath the cei l ing w i l l become thicker, the clear space above the f i r e w i l l be reduced and therefore the rate of smoke production w i l l become less and less. The magnitude of these two opposing effects wi l l depend on the circumstances prevailing in the building at the time and there w i l l , of course, be other factors operating to affect the amount of smoke produced as a f i r e develops, not least among these being the increase in heat output as the size of the Fire increases. I t is certain that even for a specific building i t is not possible to quantify these variables and any attempt to calculate the rate of smoke produced or to design a smoke control system based on a general set of conditions is not rea l i s t i c . However, one of the primary principles of f i r e protection is to make provisions in a building which w i l l either l im i t the Fire size or res t r i c t i ts spread. In a large building the insta l la t ion of sprinklers w i l l usually be specified, in which case i t is possible to assume that the Fire w i l l be limited to a size which is approximately a 3 m x 3 m square (or i ts equivalent c i rc le 3.8 m in diameter). This assumption is jus t i f i ed by records which show that in a high proportion of f i res in sprinklered premises the f i r e is controlled to a size approximating to the sprinkler head spacing. Consequently, in most smoke control designs sprinklers are specified as a firm requirement and the above Fire size is assumed in any consideration of smoke control measures."

The only way to control the amount of smoke that is generated in a building f i r e is to control the size of the f i r e . The only way to control the size of a building f i r e is with a suppression system. I t must be recognized that i t is not possible to have an ef fect ive zoned smoke control system unless there is an ef fect ive Fire control system FIRST. As Butcher and Parnell have pointed out i t is not practical nor economically Feasible to design a smoke control system for a Fire larger than 3 meters x 3 meters (5 megawatts). The ins ta l la t ion of a suppression system (sprinkler system) must be specified to insure the smoke generation rate w i l l be maintained within the smoke control system design specifications. COMMITTEE ACTION: Accept in Principle.

In I - I , second paragraph, change the second sentence to read:

"Limiting f i r e size by provision of automatic sprinklers or other means of automatic suppression w i l l generally be necessary For ef fect ive and economical control of smoke in most occupancies. Other techniques may be appropriate for specialized occupancies or existing Fac i l i t i es . " COMMITTEE COMMENT: The Committee Action should sat is fy the Commenter's intent.

(Log #88) 92A - 9 - ( I - I ) : Reject SUBMITTER: Edward O. Ward, Factory Mutual Research Corp. COMMENT ON PROPOSAL NO.: 92A-I RECOMMENDATION: Revise second sentence of second paragraph to read as follows:

"Limiting f i r e size by provision of automatic sprinklers w i l l be necessary For ef fect ive control of smoke." SUBSTANTIATION: Without automatic sprinklers, Fire development w i l l be signif icant and flashover w i l l be l i ke ly . Pressures generated under these conditions w i l l overcome the smoke control system. COMMITTEE ACTION: Reject. COMMITTEE COMMENT: See Committee Comment on Comment 92A-7 (Log #17) on Section 1-1.

(Log #138) 92A - 10 - (I-2, I-5.3, I-7, 2-1.4, Table 2-I, 3-4.3.4, 3-4.3.5): Accept in Part SUBMITTER: Donald W. Belles, Belles & Assoc., Inc. COMMENT ON PROPOSAL NO.: 92A-I RECOMMENDATION: Revise NFPA 92A, Recommended Practice For Smoke Control Systems as follows:

I. Add to paragraph I-2 Scope the Following statement:

"This practice also applies to systems dedicated solely to the control of smoke."

2. Revise paragraph I-5.3, Airflow, to read as Follows:

]-5.3 Airflow. Airf low can be used . . . such openings. A velocity of 3 m/s to 4 m/s has been suggested to prevent smoke flow through a permanent opening. Since . . . . movement.

3. Revise the f i r s t paragraph of Section I-7 to delete the terms "necessarily reduce or" so that the third sentence reads:

"Automatic suppression systems l im i t the growth rate and the maximum size of f i r e but do not eliminate the movement of smoke."

4. Revise 2-l .4, second paragraph, by deleting the expression "Theoretically, a refuge area could be designed to provide protection For any period of time. However,". The paragraph w i l l then read:

"The concept of refuge areas . . . developed." 5. Revise Table 2-I to reduce the required pressure

for buildings with automatic sprinkler protection to O.Ol.

6. Revise Section 3-4 on Controls by adding additional paragraphs and renumbering subsequent paragraphs as Follows:

3-4.3.4 Manual Activation. All smoke control systems should be designed for manual activation. Controls should be provided in the Fire Fighters smoke control station and such other locations deemed prudent.

3-4.3.5 Automatic Activation. All smoke control systems should be designed For automatic activation. Activation should occur via actuation of automatic sprinkler systems or other heat activated devices which assure the f i r e response w i l l be consistent with the smoke zone of f i r e origin. The use of smoke detectors to activate smoke control systems should be approached with care because of the poss ib i l i ty of activation of a detector outside the zone of f i r e origin.

Manual f i r e alarm pull stations should generally not be used to activate smoke control systems because of the likelihood of a person signalling an alarm from a station outside the smoke zone of f i r e origin. SUBSTANTIATION: Revision No. ] is proposed since the recommended practice applies to systems dedicated solely to the control of smoke as, For example, in the case of stairway pressurization systems.

Comment No. 2. A veloci ty of 3-4 meters/second has been Suggested by Butcher and Parnell as a means of preventing smoke flow through a permanent opening.

Comment No. 3 is viewed as an edi tor ia l revision since automatic suppression w i l l reduce or l im i t f i r e size, thereby l imi t ing the amount of smoke produced.

Comment No. 4 is an edi tor ia l suggestion to eliminate the inference that refuge areas can be designed in buildings for prolonged periods of time.

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Comment No. 5. The revision to Table 2-I to reduce the pressure to 0.01 in buildings with automatic sprinklers recognizes the f i r e pressures in sprinklered buildings w i l l be limited.

Comment No. 6. The section on Controls as currently written p~ovides no guidance as to how smoke control systems should be activated. In the absence of specific guidance, a serious deficiency exists in the Recommended Practice. COMMITTEE ACTION: Accept in Part.

I. Add the sentence proposed in point l of the Commenter's Suggested changes as a new inserted second sentence of I-2, rather than at the end of the paragraph.

2. Do not add the wording dealing with a i r velocit ies to I-5.3 as addressed by the Commenter's point 2.

3. Revise I-7 as proposed in the Commenter's point 3. 4. Accomplish the equivalent of the Commenter's

point 4 dealing with the deletion of words from 2-I .4 through the Committee Action on Comment 92A-5 (Log #16).

5. Do not revise Table 2-I as suggested by the Commenter's point 5.

6. Do not revise 3-4 as suggested by the Commenter's point 6 except as directed by the Committee Action on Comment 92A-89 (Log #5) on 3-4,3.2 which draws from this Commenter's proposed wording. COMMITTEE COMMENT: With respect to the six above actions:

I. The Commenter's additional sentence to l 2 is accepted and i n s e r t e d as a second sentence f o r b e t t e r placement and c l a r i f i c a t i o n .

2. Pressure d i f fe ren t ia l considerations w i l l provide adequate design basis without the need to specify a i r veloci t ies.

3. The Commenter's change to I-7 helps to c l a r i f y . 4. The Committee Action on Log #16 should sat isfy

the Commenter's intent with respect to the revision of 2-I .4.

5. A design pressure d i f fe rent ia l value of 0.01 w i l l not provide a safety factor. AIso, see the Committee Action on Comment 92A 43 (Log #141) on 2-2.1 which revises Table 2-I.

6. The Committee does not agree that both automatic and manual means of activation are needed. See the Committee Action on Comment 92A-86 (Log #129) on 3-4.3. However, some of the Commenter's proposed wording has been drawn upon as part of the Committee Action on Comment 92A-89 (Log #5) on 3-4.3.2 which addresses the dangers of activating systems by manual pull stations.

(Log #89) 92A - II - ( I -2 . ) : Reject SUBMITTER: Edward J. Ward, Factory Mutual Research Corp. COMMENT ON PROPOSAL NO~: 92A-I RECOMMENDATION: Revise Scope to read as follows:

"This Recommended Practice applies to the design, insta l lat ion, testing, operation and maintenance of new and re t ro f i t ted mechanical a i r conditioning and venti lat ion systems for the control of smoke in sprinklered buildings. See NFPA 204M, Guide for Smoke and Heat Venting, for smoke and heat venting." SUBSTANTIATION: Same Substantiation as stated in my comment on Section l - l . COMMITTEE ACTION: Reject. COMMITTEE COMMENT: See Committee Action on Comment 92A-7 (Log #17) on l - l .

(Log #91) 92A - 13 - ( I -2) : Reject SUBMITTER: Edward J. Ward, Factory Mutual Research Corp. COMMENT ON PROPOSAL NO.: 92A-1 RECOMMENDATION: Add the following af ter the First sentence in Scope:

"This Recommended Practice is applicable in occupancies not involving storage or manufacturing, where the quantity of combustibles present is low." SUBSTANTIATION: The Fire loading in storage and manufacturing areas would result in pressures and smoke quantities which are beyond the scope of this document. Additionally, smoke removal and incoming fresh a i r would result in a more vigorous Fire (than the same situation without smoke control) in warehouse occupancies. COMMITTEE ACTION: Reject. COMMITTEE COMMENT: The document sets out principles for smoke management. Users should operate within these principles irrespective of occupancy.

(Log #132) 92A - 14 - I-2): Accept in Principle SUBMITTER: C.V. Lovett, Easton, CT COMMENT ON PROPOSAL NO.: 92A-I RECOMMENDATION: Revise as follows:

". . . control of smoke from other than large zones such as atr ia, shopping malls, etc. type buildings." SUBSTANTIATION: The Scope does not l i s t any l imitations but Proposal 92A-I states "The problem of maintaining tenable conditions within large zones of f i r e origin, such as a t r ia and shopping malls, is not addressed by this document. This more d i f f i c u l t issue, in terms of the physics involved, w i l l be addressed later in what is planned to be a separate document, NFPA 92B" which was submitted by the Technical Committee on Smoke Management Systems the authors of this same scope. COMMITTEE ACTION: Accept in Principle.

Revise I-2 Scope statement by adding wording, From the Substantiation found in the TCR, as a new inserted third sentence, following the new sentence inserted by the Committee Action on Comment 92A-I0 (Log #138) as follows:

"The problem of maintaining tenable conditions wlthin large zones of Fire origin, such as at r ia and shopping malls, is not addressed by this document." COMMITTEE COMMENT: The Committee Action should sat isfy the Commenter's intent.

(Log #134) 92A 15 - (I-2 and 2-2.1): Accept in Principle SUBMITTER: C.V. Lovett, Easton, CT COMMENT ON PROPOSAL NO.: 92A-I RECOMMENDATION: Revise as follows:

"This recommended practice does not apply to large open f a c i l i t i e s with ceilings higher than 9 f t . " SUBSTANTIATION: What is the suggested minimum pressure differences across smoke barriers in buildings without ceilings higher than 9 ft? This document is very limited to a specific type of f a c i l i t y but i t does not state this l imitat ion. COMMITTEE ACTION: Accept in Principle.

See Committee Action on Comment 92A-14 (Log #132) on I-2. COMMITTEE COMMENT: The Committee Action on Log #132 should sat isfy the Commenter's intent.

(Log #18) 92A - 12 - ( I -2) : Reject SUBMITTER: Gunnar Heskestad, Factory Mutual Research Corp. COMMENT ON PROPOSAL NO.: 92A-l RECOMMENDATION: At the end of the f i r s t sentence, insert:

"in sprinklered buildings or occupancies with other means of automatic suppression." ~UBSTANTIATION: Provides consistency with my comment on paragraph 1-1. COMMITTEE ACTION: Rejec t . COMMITTEE COMMENT: See Committee Comment on Comment 92A-7 (Log #17) on Sec t ion 1-1.

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(Log #114) 92A - 16 - (I 4): Reject SUBMITTER: John G. Degenkolb, Carson City, NV COMMENT ON PROPOSAL NO.: 92A-I RECOMMENDATION: 1 4 Smoke Barrier, second sentence:

"A smoke barrier should have a f i r e resistance rating of not less than 45-minutes." SUBSTANTIATION: Vinyl sheeting, plain glass, Saran Wrap, etc. are not adequate to prevent passage of smoke even under low heat conditions. The 45-minute requirement would permit wired glass. qQMMITTEE ACTION: Reject. ~OMMITTEE COMMENT: Fire resistance is a function of need and should not be set a r b i t r a r i l y .

(Log #42) 92A - 17 - ( I -4) : Accept SUBMITTER: Gregory F. DeLuga, MCC Powers COMMENT ON PROPOSAL NO.: 92A-I RECOMMENDATION: Add new def in i t ion to I-4 as Follows:

Smoke Control Mode. A predefined operational configuration of a system or device For the purpose of smoke control. SUBSTANTIATION: This term is used within the document (as in 3-4.2), and i ts intended meaning should be defined. COMMITTEE ACTION: Accept.

(a) Small openings in smoke barriers such as construction jo ints, cracks, closed door gaps, and similar clearances should be addressed in terms of maintaining an adequate pressure difference across the smoke barrier, with the positive pressure outside of the smoke zone.

(b) Large openings in smoke barriers such as doors intended to be open, and other sizable openings should be addressed in terms of maintaining an adequate a i r veloci ty across the smoke barr ier, with the a i r Flow direction into the smoke zone. SVBSTANTIATION: The suggested rewording is intended to improve the present text. COMMITTEE ACTION: Accept.

(Log #144) 92A - 18 - ( I-4 and 2-1.4): Accept in Principle SUBMITTER: John H. Klote, National Bureau of Standards COMMENT ON PROPOSAL NO.: 92A-I RECOMMENDATION: Change the term "refuge area" to "temporary santuary". SUBSTANTIATION: For many people the term "refuge area" has a very long term meaning. This is not what i t means in 92A, and another term would make the document more understandable. COMMITTEE ACTION: Accept in Principle.

See Committee Action on Comment 92A-5 (Log #16). COMMITTEE COMMENT: The Committee Action on Log #16 should sat isfy the Commenter's intent.

(Log #147) 92A - 19 - ( I-4 and 2-1.4): Accept in Principle SVBMITTER: O.L. Arnold/Roll Oensen, Roll Oensen & Assoc., Inc. COMMENT ON PROPOSAL NO.: 92A-I RECOMMENDATION: Revise def in i t ion of "refuge area" as follows:

Refuge Area. An area other than the area of incidence that affords safety from Fire and smoke. SUBSTANTIATION: To maintain consistency with NFPA I01, Section 5-1.2.5. COMMITTEE ACTION: Accept in Principle.

See Committee Action on Comment 92A-5 (Log #16). COMMITTEE COMMENT: The Committee Action on Log #16 should sat isfy the Commenter's intent.

(Log #115) 92A - 20 - ( I -5) : Accept in Principle YUBMITTER: John G. Degenkolb, Carson City, NV COMMENT ON PROPOSAL NO. : 92A-I RECOMMENDATION : Provide a new I-5,1 and renumber :

I-5.1 I t is basic that the building be protected with an automatic sprinkler system i f smoke management is to be real ly ef fect ive. SUBSTANTIATION: To t ry to control smoke in a nonsprinklered building presents almost insurmountable problems and is certainly not cost e f f i c ien t . How ducts should be constructed, a i r moving equipment developed to handle actual f i r e temperatures would present insurmountable costs. Sprinkler protection makes smoke management Possible. Section I-7 is too weak. COMMITTEE ACTION: Accept in Principle.

See Committee Action on Comment 92A-7 (Log #17) on I - I . COMMITTEE COMMENT: The Committee Action on Log #17 should sat isfy the Commenter's intent.

(Log #43) 92A - 21 - ( I -6.2): Accept yVBMITTER: Gregory F. DeLuga, MCC Powers COMMENT ON PROPOSAL NO.: 92A-I RECOMMENDATION: Change I-6.2, Leakage Areas, paragraph to read as follows:

I-6.2 Leakage Area Parameters. Design c r i te r ia and acceptance testing of smoke control systems should be based upon the following parameters with reference to the Smoke Zone and ad jacent zones:

(Log #44) 92A - 22 - ( I -6.3): Reject SUBMITTER: Gregory F. OeLuga, MCC Powers COMMENT ON PROPOSAL NO.: 92A-I RECOMMENDATION: Add the following sentences at the end of the I-6.3, Weather Data, paragraph:

"Specific smoke control design c r i t e r i a to compensate for the effects of weather is not yet available. Present designs of smoke control systems should attempt to minimize the effects of wind." SUBSTANTIATION: The present paragraph needs to provide guidance or direction regarding the statements made. The suggested additional sentences add direction consistent with the ASHRAE smoke control design document. COMMITTEE ACTION: Reject. COMMITTEE COMMENT: The current d ra f t ' s treatment of the issue is adequate.

(Log #45) 92A - 23 - ( I-6.5): Reject SUBMITTER: Gregory F. DeLuga, MCC Powers COMMENT ON PROPOSAL NO.: 92A-I RECOMMENDATION: Revise paragraph I-6.5 to read as follows:

I-6.5 Pressure Di f ferent ia ls. The maximum and minimum allowable pressure d i f fe ren t ia ls across smoke barriers of smoke control zones should be a design consideration. The maximum pressure d i f fe ren t ia l should not result in door-opening Forces which exceed the requirements of NFPA I01, Life Safety Code, as well as the requirements of the local code. The minimum pressure d i f fe rent ia l should allow a tenable environment during occupancy and evacuation of the zone(s) adjacent to the smoke zone. The minimum pressure d i f fe rent ia l should also be suf f ic ient to overcome any opposing Forces of wind, building stack ef fect , and buoyancy of smoke. yVByTANTIATION: The suggested rewording is more consistent with pre-deFined terms (tenable environment vs. signif icant smoke leakage) and also improves the sentence structures within the paragraph. COMMITTEE ACTION: Reject. COMMITTEE COMMENT: The proposed text addresses only zones but ignores stairwel l issues. The general concept is adequately addressed in the TCR draft .

(Log #46) 92A - 24 - ( I -6.7): Reject SUBMITTER: Gregory F. DeLuga, MCC Powers COMMENT ON PROPOSAL NO.: 92A-I RECOMMENDATION: Add the following sentences to paragraph 1-6.7:

"In s ta i r pressurization systems, i t is reasonable to assume that the smoke zone door and the ground f loor door w i l l be open on an almost constant basis due to occupant movement and f i r e f ighting e f fo r ts . Stair pressurization systems should include this two door open scenario as a minimum design consideration." SUBSTANTIATION: The suggested additional sentences provide specific design minimums, which compliment the present content of the paragraph. COMMITTEE ACTION: Reject. COMMITTEE COMMENT: Each case should be indiv idual ly designed.

g5

(Log #92) 92A - 25 - (I-6.7): Accept SUBMITTER: Edward O. Ward, Factory Mutual Research Corp. COMMENT ON PROPOSAL NO.: 92A-]

I RECOMMENDATION: Delete the last sentence. SUBSTANTIATION: I t is impractical to expect doors to be open for such short time periods. Deleting sentence does not detract from intent of paragraph and allows a more conservative design. COMMITTEE ACTION: Accept.

(Log #94) 92A - 2B - ( ] -7) : Reject SUBMITTER: Edward J. Ward, Factory Mutual Research Corp. COMMENT ON PROPOSAL NO.: 92A-I RECOMMENDATION: Delete the f i r s t two paragraphs. SUBSTANTIATION: The document should only apply to sprinklered buildings and, as a result, these two paragraphs are not needed. COMMITTEE ACTION: Reject. COMMITTEE COMMENT: See Committee Action on Comment 92A-26 (Log #I16) and Comment 92A-27 (Log #93) on I-7.

(Log #116) 92A - 26 - ( I-7): Reject SUBMITTER: John G. Degenkolb, Carson City, NV COMMENT ON PROPOSAL NO.: 92A-1 RECOMMENDATION: Delete a l l reference to f i r e suppression systems other than automatic sprinklers. SUBSTANTIATION: The only acceptable f i r e suppression system to be used in connection with a smoke management system is the automatic sprinkler system. All reference to Halon, etc. should be deleted. I f i t is necessary to mention f i r e extinguishing gases such as Halon, C02, etc. because they are present as in a computer room, special precautions should be outlined. COMMITTEE ACTION: Reject. COMMITTEE COMMENT: Although use of automatic sprinkler systems may dominate in the design of smoke control systems, the Committee is not w i l l i ng to exclude other means of accomplishing the same result. Material needs to be retained (especially the second and third paragraphs of I-7) as a warning to the document user that smoke control systems should not interfere with the operation of other extinguishing systems which may be present. Also see Committee Action on Comment 92A-27 (Log #93) on I-7.

(Log #93) 92A - 27 - ( I-7): Accept in Principle SUBMITTER: Edward J. Ward, Factory Mutual Research Corp. COMMENT ON PROPOSAL NO.: 92A-] RECOMMENDATION: Revise the first paragraph as follows (only if my previous comment on this paragraph is not accepted):

I-7 Fire Suppression Systems. Automatic sprinkler and other suppression systems are an integral part of many f i r e protection designs and the r e l i a b i l i t y and eff ic iency of such systems in control l ing building f i res is well documented. I t is important to recognize that the functions of suppression and smoke control systems are both important. Automatic suppression systems can extinguish a f i r e early in i ts growth, thereby eliminating additional smoke generation. On the other hand, well designed smoke control systems can maintain a tenable environment along c r i t i ca l egress routes during the time i t takes the f i r e suppression system and f i re service personnel to achieve f inal extinguishment. SUBSTANTIATION: This paragraph as written implies that f i r e suppression systems alone cannot achieve the goals of both suppression and smoke control. This is not true. Automatic sprinklers without smoke control are extremely effective for protection of l i f e and property. Smoke control in the absence of sprinklers is debatable at best. COMMITTEE ACTION: Accept in Principle.

Revise the f i r s t paragraph of I-7 to read: "Automatic sprinkler and other suppression systems

are an integral part of many f i r e protection designs and the r e l i a b i l i t y and eff ic iency of such systems in controll ing building Fires is well documented. I t is important to recognize that the functions of suppression and smoke control systems are both important. Automatic suppression systems can extinguish a f i re early in i ts growth thereby eliminating additional smoke generation. On the other hand, well designed smoke control systems can maintain a tenable environment along c r i t i c a l egress routes during the time i t takes the f i r e suppression system or f i r e service personnel to achieve extinguishment. COMMITTEE COMMENT: The Committee Action should sat isfy the Commenter's intent.

(Log #19) 92A - 29 - ( I -7) : Accept in Part in Principle SUBMITTER: Gunnar Heskestad, Factory Mutual Research Corp. COMMENT ON PROPOSAL NO.: 92A-I RECOMMENDATION: Delete second paragraph and revise f i r s t paragraph to read:

"Fire Suppression Systems. Automatic sprinkler and other suppression systems are an integral part of many f i r e protection designs and the r e l i a b i l i t y and eff ic iency of such systems in controll ing building f i res is well documented. I t is important to recognize that the functions of suppression and smoke control systems are both important. Automatic suppression systems can extinguish a f i r e early in i ts growth, thereby eliminating additional smoke generation. On the other hand, well-designed smoke control systems can maintain a tenable environment along c r i t i ca l egress routes during the time i t takes the f i r e suppression system and f i r e service personnel to achieve f ina l extinguishment." SUBSTANTIATION: These changes re f lec t the re lat ive roles of the suppression system and the smoke control system in the overall protection strategy. The existing text is misleading, suggesting that a suppression system alone cannot achieve both suppression and smoke control (as related to generation of smoke). COMMITTEE ACTION: Accept in Part in Principle.

Do not delete the second paragraph but see Committee Action on Comment 92A-27 (Log #93) on 1-7. COMMITTEE COMMENT: The Committee believes that the second paragraph of I-7 needs to be retained. However, the Committee Action on Log #93 should sat is fy part of the Commenter's intent.

(Log #2) 92A - 30 - ( ] -7) : Accept in Principle SUBMITTER: Thomas C. Campbell, TIMA COMMENT ON PROPOSAL NO.: 92A-I RECOMMENDATION: Add a new sentence at the end of the second paragraph, as follows:

"Buildings for which smoke control systems are being designed, should be equipped with an automatic f i r e extinguishing system, throughout." SUBSTANTIATION: Research reported by Butcher & Parnell in "Smoke Control in Fire Safety Design", indicates that the quantity of smoke generated is proportional to the size of a f reely expanding f i r e so that i t is impractical, i f not impossible, to design a workable smoke control system, unless the size of the f i r e is controlled by an automatic f i r e suppression system. COMMITTEE ACTION: Accept in Principle.

See Committee Action on Comment 92A-8 (Log #I08) on Section l - l . COMMITTEE COMMENT: The Committee Action on Log #108 should sat is fy the Commenter's intent.

(Log #26) 92A - 31 - ( ] -8) : Accept in Principle SUBMITTER: Rob Zivney, MCC Powers COMMENT ON PROPOSAL NO.: 92A-1 RECOMMENDATION: Relocate this section (a l l three paragraphs) to 4 - ] . ] , and change f i r s t word from "Testing" to "Purpose". Renumber existing 4- ] . I to 4-1.2.

g8

SUBSTANTIATION: I t is awkward and confusing to present this subject in three separate places in the text (Note: Section l-6.1 covers the same subject under Design Parameters). Chapter 4 "Testing" is the most appropriate location for this information, and is where a user w i l l look for guidance on the subject. COMMITTEE ACTION: Accept in Principle.

Move a l l three paragraphs of proposed I-8 to become a new 4- I . I and delete the boldface t i t l e "Testing" from the beginning of the f i r s t paragraph.

Renumber TCR paragraph 4- I . I as 4-1.2. Create a I-8 as follows: I-8 Testing. See 4-I.

COMMITTEE COMMENT: The Committee Action should sat is fy the Commenter's intent.

(Log #27) 92A - 32 - ( I -9) : Accept in Principle SUBMITTER: Rob Zivney, MCC Powers COMMENT ON PROPOSAL NO.: 92A-I RECOMMENDATION: Relocate this paragraph to 4-4.1 and renumber existing paragraphs accordingly. SUBSTANTIATION: I t is awkward and confusing to cover the same subject in two remote parts of the text, under two di f ferent names. By placing the text under Periodic Testing i t more c lear ly draws the correlation between the two terms. COMMITTEE ACTION: Accept in Principle.

Move proposed I-9 to become a new 4-4.1 and delete the boldface t i t l e "Maintenance" from the beginning of the paragraph.

Renumber TCR paragraphs 4-4.1 through 4-4.3 as 4-4.2 through 4-4.4.

Create a I-9 as follows: I-9 Maintenance. See 4-4.

COMMITTEE COMMENT: The Committee Action should sat is fy the Commenter's intent.

(Log #I04) 92A - 33 - ( 2 - I . I ) : Reject SUBMITTER: francis J. McCabe, Prefco Products, Inc. COMMENT ON PROPOSAL NO.: 92A-I RECOMMENDATION: Add new paragraph:

2 - ] . l . l Smoke Systems Performance Improvements to the Fire Barrier Systems. Smoke control systems are based on two important and separate aspects. First , they attempt to control the dynamics of the buildings a i r Flows to obtain improved safety from smoke. Second, is the f i r e barr ier aspect where the smoke system requirements have caused the correction and upgrading of the long rel ied on f i r e zone barr ier system in two ways:

(1) that the smoke control system components and general construction requirements are improved and leakage-rated to perform in elevated temperatures, and

(2) many components would be predisposed to the safety position by an advance signal from the smoke detector. SUBSTANTIATION: Smoke systems have been proferred (sic) with l i t t l e reference to their evolution from the f i r e zone barrier- systems. I t would help overcome some objections i f the contributions made to the barr ier system by smoke system technology were mentioned in the document. This would serve to inform the f i r e services that smoke systems enhance and improve the barr ier systems.

While smoke c o n t r o l may ye t be in the development stage and is ye t to have i t s techno logy comp le te l y eva lua ted by code a u t h o r i t i e s and f i r e F i g h t e r s , the acceptance o f smoke c o n t r o l could be done by those people who might o b j e c t to the a i r dynamics aspect on the basis o f the improvement to the b a r r i e r system. ~OMMITTEE ACTION: Re jec t . COMMITTEE COMMENT: The change suggested by the Commenter is not a p p r o p r i a t e to the 2-1.1 purpose s ta tement and would serve to confuse.

(Log #107) 92A - 34 (2-I .1) : Reject SUBMITTER: francis J. McCabe, Prefco Products, Inc. COMMENT ON PROPOSAL NO.: 92A-I RECOMMENDATION: Add to second paragraph:

" . . . construction as i l lus t ra ted in Figure 2-1, and l isted in Table 2-I (Table 2-I shown on following page)."

1 H O l l l I I l l W ! 1 U i l l N l l T A L l

I l I I A l l O l l / O i J I C T l l l l

| I I l l ~ l l I I f l A l I O I l ,

(1) I ~ - l l l l l | l . a l l l i

(c) l I IE ZOICE. ~ & l l l l

\

]\ / - - ( C l ) ~ ~ a . - ~ , ,~eI l~T - SSO°V

Il lO ATI¥1I (of ~ A L ) l ~ W l l l

(C)) S ~ S (~wIa~OL - U.DSl I } O ° r

SUBSTANTIATION: Smoke systems acceptance by f i r e and code authorities has been inhibited by: l ) the lack of f i r e zone ident i f icat ion and ver i f i ca t ion from smoke only zones, and 2) the need for c la r i f i ca t i on of the basic objectives and functions of smoke control. The omission of components operation per system function has further exacerbated this problem. Substantiation is the over 12 years of systems incubation with continued misinterpretation of systems functioning. COMMITTEE ACTION: Reject. COMMITTEE COMMENT: The Comment introduces material and concepts which have not had public review. The Commenter is encouraged to submit the material as public proposals following the publication of NFPA 92A when public proposals are once again being accepted.

(Log #47) 92A - 35 - (2-1.2.2(b)I): Accept SUBMITTER: Gregory F. DeLuga, MCC Powers COMMENT ON PROPOSAL NO.: 92A-1 RECOMMENDATION: Revise 2-1.2.2(b)1 as follows:

I. Component fai lures of equipment which is required for normal building operation are less l i ke l y to remain uncorrected. SUBSTANTIATION: The suggested rewording is intended as an improvement on the present wording. ~OMMITTEE ACTION: Accept.

(Log #48) 92A - 36 - (2-1.2.2(c)2): Accept SQBMITTER: Gregory F. DeLuga, MCC Powers COMMENT ON PROPOSAL NO.: 92A-1 RECOMMENDATION: Revise 2-I.2.2(c)2 as follows:

2. Inadvertant modification of controls affecting smoke control funct ional i ty is more l i ke l y to occur. SUBSTANTIATION: The suggested rewording is intended to more speci f ica l ly address the concern. COMMITTEE ACTION: Accept.

97

SM(EE SYST~4$ Iro'NCTIONS WITH DAMPER POSITI(~S

FUNCTION

Pressurization

Exhaust

IContainment

IPurge

NOTES: (i)

(2)

(3)

ZONE

Non-Fire No Smoke

"C" Fire Zone

"C" Fire Zone

I "B" Non-Fire With Smoke

"C" Alternate Choice in Fire Zone

I I

PHASE I OONTR~

I I I I Automatic I I I Fire Fighter

ql & (3~.~ Supervision Only IUL33 Automatic I Immediate Response | to Heat with I Actuator Disconnect

2 I

11 & (3)

I I"B" Automatic

In Non-Fire Zones l"c" Before 350°F I or After

Under 15O°F ~Fire Fighter Super- I vision Recommended

TEMPERATd RE

Ambient

Ambient to 350°F &

Below 150°F

450°F to 2OO0°F

Ambient to 350°F &

Below 150°F

DAMP

~PPL~

Open

Closed

Closed

Open

R PO S I DEDI~TED

Closed

___Open IClosed (or [Open directly IOver tbe Fire lOt By ISupervision)

Open

ION

RETU P,N

Closed

Open

Closed

Open

Appropriste fans would be on i00%.

The system recirculating or return air damper would be closed for 100% intake and i00% exhaust.

There should be at least 2 intakes on the supply side & the 2 intakes are to be controlled and placed so as to differentiate the windward & leeward (smoke free vs. smoke f~lled) side of the building.

TAB~Iz 2-1

(Log #119) 92A - 37 - (2-1.3) : Reject SUBMITTER: John G. Degenkolb, Carson City, NV COMMENT ON PROPOSAL NO.: 92A-] RECOMMENDATION: Delete fourth l ine . SUBSTANTIATION: At present the so-cal led Model Codes do not have spec i f ic requirements fo r smoke management - a t e rm n o t even to be Found. I t was a n t i c i p a t e d t h a t 92A would p r o v i d e the necessa ry i n f o r m a t i o n but i t doesn't do so. COMMITTEE ACTION: Reject. COMMITTEE COMMENT: The Commenter's proposed change is not understood. Deletlng the fourth l i ne would resu l t in an incomplete sentence.

(Log #118) 92A - 38 - (2-2.1) : Reject SUBMITTER: John G. Degenkolb, Carson City, NV COMMENT ON PROPOSAL NO.: 92A-I RECOMMENDATION: In Table 2- I , which Follows the wording of 2-2.1:

Delete Note I. Delete NS l ine . Change AS l ine Design Pressure to 0.03

SUBSTANTIATION: While i t is acknowledged that Stack e f f e c t and wind are s t r o n g f a c t o r s , we d o n ' t r e a l l y know enough about how to hand le them a t t h i s t i m e . I f t hey a re i n c l u d e d we end up w i t h the s i t u a t i o n where we are damned e i ther way we go.

As previously stated, smoke management can ' t reasonably be expected with free burning f~re. The pressures referenced aren ' t r e a l i s t i c . Tamura has reported 0.16 which is .04 higher than any I ' ve seen reco rded so no marg ln f o r e r r o r is p r o v i d e d .

Ben jamin o r i g i n a l l y p rov ided the 0 .05 f i g u r e For AS s i t u a t i o n s but d id acknowledge t h a t 0.01 t o 0 .02 are f a r more r e a l i s t i c . So, 0 .03 would p r o v i d e an adequate safety margin. ¢OMMITTEE ACTION: Reject.

COMMITTEE COMMENT: With respect to the Commenter's proposed delet ions, see Committee Action on Comment 92A-7 (Log #17) on l - l . With respect to changing the design pressure d i f f e r e n t i a l , see Committee Action on Comment 92A-43 (Log #141) on 2-2.1. The pressure d i f f e r e n t i a l of 0.03 would not provide an adequate Factor of safety.

(Log #20) 92A - 39 - (2 2.1): Accept in Pr inc ip le SUBMITTER: Gunner Heskestad, Factory Mutual Research Corp. COMMENT ON PROPOSAL NO.: 92A-1 RECOMMENDATION: Change Note l of Table 2-I to read:

"For representatlve wind condit ions and stack e f f e c t . " SUBSTANTIATION: Present wording is ambiguous as to how the designer incorporates ef fects of wind and temperature. The new wording makes i t incumbent upon the designer to provide the needed pressure di f ferences, whatever the spec i f ic e f fects of wind and temperature might be. COMMITTEE ACTION: Accept in Pr inc ip le .

See Committee Action on Comment 92A 43 (Log #141) on 2-2.1. COMMITTEE COMMENT: The Committee Action on Log #141 should sa t i s fy the Commenter's in tent .

(Log #21) 92A - 40 - ( 2 - 2 . 1 ) : R e j e c t SUBMITTER: Gunnar Heskes tad , F a c t o r y Mutua l Research Corp. COMMENT ON P R O P O S A L ~ : 92A-1 RECOMMENDATION: I n Tab le 2 - I , d e l e t e column BLDG TYPE and second row i n t a b l e . Change e n t r y f o r DESIGN PRESSURE From 0 .5 to 0 .15 and e n t r i e s For PERMISSIBLE - - f rom .02 to 0 . 0 6 . D e l e t e Note 2.

98

SUBSTANTIATION: Existing recommended pressure differences appear too small, even for sprinklered f i res , when volume expansion pressures of the f i r e are considered. We have measured volume expansion pressures on the order of 0.5 in. water gage and higher. Changing From 0.05 to O.15 insures that a far greater fract ion of systems w i l l actually achieve smoke control. COMMITTEE ACTION: Reject. COMMITTEE COMMENT: The Comment introduces material and concepts which have not had public review. The Commenter is encouraged to submit the material as public proposals following the publication of NFPA 92A when public proposals are once again being accepted.

(Log #9S) 92A - 41 - (2-2.1): Reject SUBMITTER: Edward O. Ward, Factory Mutual Research Corp. COMMENT ON PROPOSAL NO.: 92A-l RECOMMENDATION: Revise Table 2-I by deleting a l l references to nonsprinklered buildings and increasing the minimum pressure differences from "O.OS" to "0.15" and from "0.02" to "0.06" For sprinklered buildings. SUBSTANTIATION: The pressure differences presented are inadequate or minimal at best. Fully developed f i res and flashover conditions w i l l develop pressures Far in excess of those figures given for nonsprinklered buildings. The pressures given For sprinklered buildings are minimal and are not l i ke ly to overcome pressure differences caused by wind, especially for high rise buildings. COMMITTEE ACTION: Reject. COMMITTEE COMMENT: The Comment introduces material and concepts which have not had public review. The Commenter is encouraged to submit the material as public proposals following the publication of NFPA 92A when public proposals are once again being accepted.

(Log #28) 92A - 42 - (2-2.1 and 2-2.2): Accept in Principle SUBMITTER: Rob Zivney, MCC Powers COMMENT ON PROPOSAL NO.: 92A-I RECOI~MENDATION: Add the following to paragraph 2-2.1:

"These pressure differences are between the smoke zone and adjacent smoke control zone, Floor, or s ta i rwel l , while the affected areas are in the smoke control mode. The short term pressures recognize a temporarily reduced pressure d i f ferent ia l as a result of the design number of doors being open continuously. This temporarily reduced pressure d i f ferent ia l is the characteristic response time of the smoke control system."

Replace the First sentence of 2-2.2 with the following:

"Similarly, the pressure differences across a f u l l y closed door between the smoke zone and adjacent smoke control zone, f loor , or s ta i rwel l , while the affected areas are in the smoke control mode, should not exceed the values given in Table 2-2 SO that the door can be operated." SUBSTANTIATION: Current text of 2-2.1 is unclear as to whether the design conditions are the normal or the smoke control mode in Note 3 includes purpose and use of stated.

Text of 2-2.2 is c la r i f i es that the COMMITTEE ACTION:

, and i f the adjacent area referenced the stairwel l or not. Also the the short term pressure is not

made consistent with 2-2.1 and situation is a f u l l y closed door. Accept in Principle.

Rather than doing as the Commenter suggests, revise Note 3 to Table 2-I to read:

NOTE 3: The pressure difference measured between the smoke zone and adjacent spaces, while the affected areas are in the smoke control mode.

COMMITTEE COMMEN!: The Committee Action should meet the Commenter's intent.

(Log #141) 92A - 43 - (2-2.1): Accept in Principle SUBMITTER: John H. Klote, National Bureau of Standards COMMENT ON PROPOSAL NO.: 92A-l RECOMMENDATION: Revise as follows:

2-2.1 * The following Table of suggested minimum design pressure differences was developed for gas temperature of 1700°F next to the smoke barrier.

Table 2-I Suggested Minimum Design Pressure Difference Across Smoke

Barriers (~) (Inches Water Gage)

DESIGN BLDG CEILING PRESSURE TYPE (2) HEIGHT DIFFERENCE

AS ANY 0.05 NS 9 f t 0.10 NS 15 f t 0.14 NS 21 f t 0.18

NOTE l : For design purposes, a smoke control system should maintain these minimum pressure differences under l i ke l y conditions of stack ef fect or wind.

NOTE 2: AS - Sprinklered, NS - Nonsprinklered.

I f i t is desired to calculate pressure differences For gas temperatures other than 1700°F, the method described in Appendix A may be used. Pressure differences produced by smoke control systems tend to Fluctuate due to the wind, fan pulsations, doors opening, doors closing~ and other Factors. Short term deviations from the suggested minimum design pressure difference may not have a serious effect on the protection provided by a smoke control system. There is no clear cut value of allowable value of this deviation. I t depends on tightness of doors, tightness of construction, t ox i c i t y of smoke, a i r Flow rates, and on the volumes of spaces. Intermittent deviations up to 50 percent of the suggested minimum design pressure difference are considered tolerable in most cases. SUBSTANTIATION: Pressure differences Should be given for heights other than 9 Ft. The proposed text ref lects the nature of pressure Fluctuations in a more meaningful way. ~OMMITTEE ACTION: Accept in Principle.

Revise Table 2-I and add revised 2-2.1 wording as suggested by the Commenter and reinsert Note 3 (as revised by Committee Action on Comment 92A-42 (Log #28)) as found in the TCR. COMMITTEE COMMENT: The Committee Action should sat is fy the Commenter's intent.

(Log #112) g2A - 44 - (2-2.2 Note 6 (New)): Accept SUBMITTER: James A. Milke, Columbia, MD COMMENT ON PROPOSAL NO.: 92A-l RECOMMENDATION: Add Note 6:

6. Door widths apply only i f door is hinged at one end, otherwise use the calculation procedure provided in the ASHRAE publication "Design of Smoke Control Systems for Buildings". SVBSTANTIATION: Maximum pressure difference calculation is based on summing moments about pivot axis For door. I f the pivot axis is not located at the door edge, then the actual door width minus the knob-to-edge distance is not the appropriate moment arm. COMMITTEE ACTION: Accept.

(Log #113) 92A - 45 - (2-2.2 Note 4): Accept SUBMITTER: James A. Milke, Columbia, MD COMMENT ON PROPOSAL NO.: 92A-l RECOMMENDATION: Revise Note to read:

4. For other door opening forces, other door sizes or hardware other than a knob, e.g., panic hardware, use the calculation procedure provided in the ASHRAE publication "Design of Smoke Control Systems for Buildings".

99

SUBSTANTIATION: Calculation of maximum pressure difference is dependent on moment arm of the Force applied by occupant using door hardware. Panic hardware w i l l provide a moment arm, r, which is d i f ferent from that of a knob. The moment arm for the panic hardware case w i l l be near the center of the door i f the applied force is distributed evenly to both points of attachment of the door. COMMITTEE ACTION: Accept.

(Log #120) 92A - 46 - (2-2.2): Reject SUBMITTER: John G. Degenkolb, C~rson City, NV COMMENT ON PROPOSAL NO.: 92A-I RECOMMENDATION: Needs considerably more input from the Committee and, possibly, From the hardware industry. SUBSTANTIATION: Insuf f ic ient consideration has been given to the force of the door closer i t se l f , the weight of the door, the type of hinge, etc. I t should be suf f ic ient to state that the Force needed to start the door moving should not exceed 30 pounds. Here, again, i f you introduce wind and stack action you WON'T be able to comply with the 30 Ibf . COMMITTEE ACTION: Reject. COMMITTEE COMMENT: The Commenter has not provided any specific wording, however, see Comments 92A-44 (Log #I12) and 92A-45 (Log #I13) on 2-2.2 which should meet some o f the Commenter 's c o n c e r n s .

(Log #liT) 92A - 47 - (2-3.1): Reject SUBMITTER: John G. Degenkolb, Carson City, NV COMMENT ON PROPOSAL NO.: 92A-1 RECOMMENDATION: Revise as Follows:

2-3.l Stairtower Pressurization. New second sentence:

"Stairwell pressurization should be in i t ia ted by smoke detectors positioned on the building in ter ior side of the stairtower adjacent to each doorway and by actuation of the sprinkler system protecting that area. Upon actuation of either, the pressurization system For that stairtower should be actuated and a l l doors into the stairtower close and latch. SUBSTANTIATION: No provision has been made For actuation of the pressurization system. COMMITTEE ACTION: Reject. COMMITTEE COMMENT: Provision has been made. See oaragraph 3-4.4. Controls For s ta i r pressurization systems are covered elsewhere in the document.

(Log #145) 92A - 48 - (2-3.1): Accept SUBMITTER: D.L. Arnold/Roll Jensen, Roll Jensen & ASSOC., I n c . COMMENT ON PROPOSAL NO.: 92A-l

I RECOMMENDATION: Delete "smoke-Free" From paragraph. SUBSTANTIATION: Change maintains consistency with last sentence of paragraph ( i . e . , "smoke i n f i l t r a t i o n is l imited"). COMMITTEE ACTION: Accept.

(Log #121) 92A - 49 - (2-3.2): Reject YUBMITTER: John G. Degenkolb, Carson City, NV COMMENT ON PROPOSAL NO.: 92A-l RECOMMENDATION: This section is very d i f f i c u l t to understand and application to a job s i te is impossible.

a) What is a "low population density and low f i r e loading"? Why is i t dismissed in such a cavalier fashion. An of f ice building has a low population density and we are certainly concerned with f i r e safety therein.

b) No information is provided as to minimum a i r velocit ies. This is supposed to be a Recommended Practice, one step above a Guide and ought to provide some specific information.

SUBSTANTIATION: A half page is given over to discuss some abstract subjects but no guidance is given as to how to proceed with i t . Terminology is new and not understood by the Mechanical Engineers and Building OFFicials with whom I have had discussions. COMMITTEE ACTION: Reject. COMMITTEE COMMENT: The Commenter has not provided any specific suggested wording changes. The Commenter is encouraged to submit public proposals, with specific wording, Following the publication of NFPA 92A when public proposals are once again being accepted.

(Log #139) 92A - 50 - (2-3.2(a)): Accept in Principle SUBMITTER: T Daly/H. Moore, Hilton Hotels Corpl COMMENT ON PROPOSAL NO.: 92A-I

I RECOMMENDATION: Delete second sentence and Return to Committee For Further Study. SUBSTANTIATION: The terms "low population density" and "low Fire loadings" are undefined, subjective and do not correlate with other NFPA definit ions in either the Life Safety Code (low hazard) or the sprinkler standard ( l igh t hazard). The introduction of new undefined terms tends to make application and enforcement more d i f f i c u l t . COMMITTEE ACTION: Accept in Principle.

Delete the second sentence but do not "Return to Committee". COMMITTEE COMMENT: The Committee Action of deletlng the sentence should satisfy the Commenter's intent.

(Log #49) 92A - 51 - (2-3.2): Reject SUBMITTER: Gregory F. DeLuga, MCC Powers COMMENT ON PROPOSAL NO.: 92A-I RECOMMENDATION: Revise 2-3.2(b)(I) Notes l as Follows:

I. Fan bypass controlled by one or more stat ic pressure sensors, arranged to sense the d i f fe rent ia l pressure between the stairtower and the building exterior. SUBSTANTIATION: Existing text cal ls For the stat ic pressure to be sensed between the stairtower and the building inter ior . However, in order For the stairtower static pressure to be optimum with respect to the smoke zone, the "building in ter ior " serving as the reference would have to be the smoke zone. Since this cannot be known beforehand, the next best reference is the building exter ior. Other building in ter ior points cannot be used For reference since they may be pressurized zones. COMMITTEE ACTION: Reject. COMMITTEE COMMENT: The concern is the pressure d i f fe rent ia l between the s ta i r enclosure and the f i r e Floor. Thus, the TCR wording is correct.

(Log #30) 92A - 52 - (Figure 2-3.2(b)( l ) ) : Reject SUBMITTER: Rob Zivney, MCC Powers COMMENT ON PROPOSAL NO.: 92A-l RECOMMENDATION: In Note I change "located" to "that sense pressure between the stairtower and the building exter ior". SUBSTANTIATION: The function of the sensor ~s important, not the location. The building exter ior is the reference For controls, since i t is more constant, and common to a l l Floors. COMMITTEE ACTION: Reject. COMMITTEE COMMENT: See Committee Action on Comment 92A-51 (Log #49) on 2-3.2(b)(I).

(Log #29) 92A - 53 - (2-3.2(b)(I)) : Reject yUBMITTER: Rob Zivney, MCC Powers COMMENT ON PROPOSAL NO.: g2A-I RECOMMENDATION: Delete the last sentence. SUBSTANTIATION: No purpose or guidelines For consideration are established. COMMITTEE ACTION: Reject. COMMITTEE COMMENT: Deletion would lead to response time not being considered. I t should be considered.

100

(Log #146) 92A - 54 - (2-3.2(b)(2)): Reject SUBMITTER: D.L. Arnold/Roll Jensen, Roll Jensen & Assoc., Inc. COMMENT ON PROPOSAL NO.: 92A-I RECOMMENDATION: Delete second paragraph regarding the discharge of s ta i r pressurization into existing buildings in i ts ent i rety. SUBSTANTIATION: Discharging over-pressure r e l i e f into existing buildings w i l l reduce the building's f i r e safety by violat ing the passive in tegr i ty with active components and increasing the potential for spreading contaminated outside a i r through the building. COMMITTEE ACTION: Reject. COMMITTEE COMMENT: Discharge of s ta i r pressurization into buildings is a viable method of rel ieving overpressure in existing buildings where the existing construction and physical constraints preclude other r e l i e f d i rect ly to the outside.

(Log #31) 92A - 55 - (2-3.2(b)(2)(a)): Accept SUBMITTER: Rob Zivney, HCC Powers COMMENT ON PROPOSAL NO.: 92A-I

I 'RECOHMENDATION: In l ine 9, change " re f lec t " to "allow the system to meet". SUBSTANTIATION: Existing wording is awkward and can be misleading. COMMITTEE ACTION: Accept.

(Log #50) 92A - 56 - (2-3.2(b)(2)(a)): Accept in Principle SUBMITTER: Gregory F. DeLuga, MCC Powers COMMENT ON PROPOSAL NO.: 92A l RECOMMENDATION: Revise 2-3.2(b)(2)(a), Fourth sentence as Follows:

"The location of barometric r e l i e f dampers must not be in close proximity to the stairtower a l r supply openings, otherwise the dampers may open prematurely and not allow the proper stat ic pressure level to be achieved throughout the stairtower. SUBSTANTIATION: The revision is suggested as a refinement of the present text. COMMITTEE ACTION: Accept in Principle.

See Committee Action on Comment 92A-55 (Log #31) on 2-3.2(b)(2)(a). COMMITTEE COMMENT: The Committee Action on Log #3l should sat isfy the Commenter's intent.

(Log #5l) 92A - 57 - (2-3.3.1): Accept SUBMITTER: Gregory F. DeLuga, MCC Powers COMMENT ON PROPOSAL NO.: 92A-1 RECOMMENDATION: Interchange the content of paragraphs 2-3.3.1 and 2-3.3.2. SUBSTANTIATION: This change is suggested to present the information on potential smoke entering the stairtower before the need for automatic shutdown due to such smoke. COMMITTEE ACTION : Accept.

(Log #52) 92A - 58 - (2-3.3.1): Reject SUBMITTER: Gregory F. DeLuga, MCC Powers COMMENT ON PROPOSAL NO.: 92A-I RECOMMENDATION: Revise 2-3.3.1 as follows:

2-3.3.1 Since a stairtower pressurization system poses the potential for injecting smoke into the sta i rwel l , a stairtower pressurization system should be arranged to automatically shutdown a pressurization fan upon detection of smoke entering the stairway by means of the pressurization fan. SUBSTANTIATION: This revision is suggested as an improvement to the existing text. COMMITTEE ACTION: Reject. q0HMITTEE COMMENT: The "should be considered" wording from the TCR would be lost i f the Commenter's proposed changes were accepted. The option is needed.

(Log #32) 92A - 59 - (2-3.4. l (a)) : Accept SUBMITTER: Rob Zivney, MCC Powers COMMENT ON PROPOSAL NO,: 92A-I RECOMMENDATION: In (a), revise f i r s t sentence as follows:

"Simple single point injection systems such as that i l lus t ra ted in Figure 2-3.4.1 may use a roof or exter ior wall mounted propeller fan."

Delete paragraph (b) and renumber remaining paragraphs accordingly. SUBSTANTIATION: Presents concepts more clearly, without redundancy. q0MMITTEE ACTION: Accept.

(Log #122) 92A - 60 - (2-3.4.1(a)): Reject SUBMITTER: John G. Degenkolb, Carson City, NV COMMENT ON PROPOSAL NO.: 92A-1 RECOMMENDATION: This statement indicates i t is sat isfactory to introduce a i r d i rect ly into the stairway From the roof - probably based on Fung's work which has been shown in various f ie ld tests to be incorrect. In at least 3 instal lat ions I am aware of, this was an absolute fa i lure. SubseQuently i t was discussed with NBS to find out i f there was any way that the Bulletin by rung could be rescinded. There wasn't. I t was acknowledged to be incorrect. I t is essential that a i r be introduced at the bottom. The fan may be at the roof and ducted down but i t must not be introduced into the sta i r enclosure at the top. SUBSTANTIATION: As stated above. COMMITTEE ACTION: Reject. COMMITTEE COMMENT: The Commenter has not provided specific recommended changeS. The Committee feels that viable systems can have a i r entering From places other than just the bottom of s ta i r enclosures.

(Log #53) 92A - 61 - (2-3.4.1(a)): Accept in Principle SUBMITTER: Gregory F. DeLuga, HCC Powers COMMENT ON PROPOSAL NO.: 92A-I RECOMMENDATION: Revise 2-3.4.1(a) as Follows:

(a) A simple single point injection system such as that i l lust rated in Figure 2-3.4.1, may use a roof or wall mounted propeller Fan. SUBSTANTIATION: The revision addresses both roof and wall mounted fans. The subject of windshields should be treated as a separate item. COMMITTEE ACTION: Accept in Principle.

See Committee Action on Comment 92A-59 (Log #32) on 2-3.4.1. COMMITTEE COMMENT: The Committee Action on Log #32 should sat isfy the Commenter's intent.

(Log #54) 92A - 62 - (2-3.4.1(b)): Reject SUBMITTER: Gregory F. OeLuga, MCC Powers COMMENT ON PROPOSAL NO.: 92A-I RECOMMENDATION: Change 2-3.4.1(b) to 2-3.4.1(c), and revise the text as follows:

(c) Propeller fans generally produce lower d i f fe rent ia l pressures than centrifugal, tubeaxial, and vaneaxial fans, and are thus most susceptable to the adverse affects of wind pressures. The potential adverse effects of wind are minimized when propeller fans are located on roofs due to the shielding generally provided by parapets, and the usual wind direction being perpendicular to the fan axis. SUBSTANTIATION: The revision is suggested as an enhancement of the existing text and in the order of presentation. COMMITTEE ACTION: Reject. COMMITTEE COMMENT: The Commenter's proposed wording does not enhance the TCR wording. AIso, the Committee Action on Comment 92A-59 (Log #32) on 2-3.4.l has deleted subpart (b).

101

(Log #55) 92A - 63 - (2-3.4.2): Accept in Principle SUBMITTER: Gregory F. DeLuga, MCC Powers COMMENT ON PROPOSAL NO.: 92A-I RECOMMENDATION: Change 2-3.4.2 to 2-3.4.1(d), and revise the text as Follows:

(d) Propeller fans mounted on walls pose the greatest susceptability to the adverse affects of wind pressures. The adverse affect w i l l be maximum when wind direction is in direct opposition to the fan a i r flow, resulting in a lower intake pressure and thus s ign i f icant ly reducing fan effectiveness. Winds which are variable in intensity and direction also Pose a detrimental effect on the a b i l i t y of the system to maintain control over the stairwel l s tat ic pressure. Wall mounted propeller Fans should thus always have an adequate windshield due to this Potential ly extreme adverse effect of wind. SUBSTANTIATION: The revision is suggested as an enhancement of the existing text. COMMITTEE ACTION: Accept in Principle.

Revise as Suggested by the Commenter, but do not use (therefore, delete) the Commenter's proposed last sentence dealing with wall mounted propeller Fans and windshields. COMMITTEE COMMENT: The Committee disagrees with the proposed last sentence and Feels that i t does not provide the necessary guidance under most conditions. Acceptance of the remainder of the Commenter's suggested verbiage should sat isfy the Commenter's intent.

(Log #123) 92A - 64 - (2-3.5. I (c)) : Reject SUBMITTER: John G. Degenkolb, Carson City, NV COMMENT ON PROPOSAL NO.: 92A 1 RECOMMENDATION: Delete 2-3.5.1(c) text. SUBSTANTIATION: See comments made on 2-3.4.1(c).

An incorrect statement and, based on many real f i r e tests as Far back as 1962 when the concept was First introduced in San Diego, CA the exact reverse is true. When a i r was introduced low and doors were opened, the system s t i l l worked. When a i r was introduced at the top and doors were opened, the s ta i r Failed to remain tenable. COMMITTEE ACTION: Reject. COMMITTEE COMMENT: Injection at points other than the bottom of the shaft enclosure is viable.

(Log #56) 92A - 65 - (2-3.5.1): Accept SUBMITTER: Gregory F. OeLuga, MCC Powers COMMENT ON PROPOSAL NO.: 92A-I RECOMMENDATION: Revise 2-3.5.1(c) as Follows:

(c) Because a ground level stairtower door is l i ke l y to be in the open position much of the time, a single bottom injection system is especially prone to fa i lure . Consideration of this specific situation as wel l as o v e r a l l c a r e f u l design a n a l y s i s is r e q u i r e d f o r a l l s i n g l e bottom i n j e c t i o n systems, and f o r a l l o t h e r single injection systems for stairtowers in excess of lO0 f t in height. SUBSTANTIATION: The revision is suggested as an improvement to the existing text. COMMITTEE ACTION: Accept.

(Log #124) 92A - 66 - (2-3.6): Reject SUBMITTER: ,John G. Degenkolb, Carson City, NV COMMENT ON PROPOSAL NO.: 92A-I RECOMMENDATION: Delete last sentence of 2-3.6. SUBSTANTIATION: Incorrect statement.

In the last sentence the statement is incorrect. Codes require that the vestibule be negative with 150 percent exhaust and I00 percent supply i f done mechanically and i t has worked most successfully. I f i t is a nonmechanical vestibule i t must be open to the exter ior of the building with an opening of at least 16 sq f t - and not into a l ight shaft or similar.

COMMITTEE ACTION: Reject. COMMITTEE COMMENT: Existing code requirements should not dictate what this recommended practice describes. The draft TCR wording adequately describes viable options.

(Log #125) 92A - 67 - (2-3.6(b)): Reject SUBMITTER: John G. Degenkolb, Carson City, NV ~O.MMENT ON PROPOSAL NO.: 92A-I RECOMMENDATION: Delete 2-3.6(b). SUBSTANTIATION: An incorrect statement. Shern wrote an a r t i c le in the old NFPA Quarterly about 1963 describing a variety of real Fire tests which, in turn, contradict the statements made. I conducted a series of tests in a building to be abandoned in San Diego. Instrumentation was done by the Los Angeles Fire Department with Shern in charge. The tests were redone in a 7-story building in Los Angeles and again under Shern's direction. The results and Findings of those tests are printed in the Quarterly and are the basis for current code requirements. ~MMITTEE ACTION: Reject. COMMITTEE COMMENT: See Committee Action on Comment 92A-66 (Log #124) on 2-3.6.

(Log #33) 92A - 68 - (2-3.7): Accept SUBMITTER: Rob Zivney, MCC Powers COMMENT ON PROPOSAl NO.: 92A-I

I RECOMMENDATION: In second sentence, change "The intent" to "A benefit". ~BSTANTIATION: This Feature is not the sole, or even primary intent of Fire Floor exhaust. COMMITTEE ACTION: Accept.

(Log #7) 92A - 69 - (2-4.1): Accept SUBMITTER: J. Brooks Semple, Smoke/Fire Risk Management, Inc. COMMENT ON PROPOSAL NO.: 92A-I RECOMMENDATION: Rearrange order of l i s t , without text changes:

(a) Exhaust of the f i r e f loor . (b) Pressurization of the elevator lobbies. (c) Construction of smoke t ight elevator lobbies. (d) Pressurization of the elevator hoistway.

SUBSTANTIATION: The more popular and practical method (item (b) above) should be shown in a p r i o r i t y position over lesser direct treatments of the elevator problem. COMMITTEE ACTION: Accept.

(Log #126) 92A - 70 - (2-4(b), (c), and (d)): Reject SUBMITTER: John G. Degenkolb, Carson City, NV ~MMENT ON PROPOSAL NO.: 92A-I RECOMMENDATION: Revise to combine (b), (c), (d). SUBSTANTIATION: Without elevator lobby separation, Pressurization of the hoistway would result in more or less equal pressurization of a l l f loors served by the elevators. Hoistway doors are anything but smoke t ight and there is no correction of that problem in the forseeable future for high rise buildings. COMMITTEE ACTION: Reject. COMMITTEE COMMENT: Three separate paragraphs stress three separate alternatives and each is viable alone. Elevator hoistway pressurization can and does work, without always having to provide a smoketight lobby.

(Log #142) 92A - 71 - (2-4.2): Accept ~UBMITTER: John H. Klote, National Bureau of Standards COMMENT ON PROPOSAL NO.: 92A-I RECOMMENDATION: Delete "successfully" in the f i r s t sentence. SUBSTANTIATION: These methods have been employed, but thei r success in control l ing smoke movement during building f i res has not been proven. COMMITTEE ACTION: Accept.

102

(Log #135) 92A - 72 - (2-5.2): Accept in Principle yVBMITTER: C.V. Lovett, Easton, CT ~QHHENT ON PROPOSAL NO.: 92A-1 RECOMMENDATION: Rev ise as F o l l o w s :

" S o m e / C e r t a i n b u i l d i n g s can be . . . . " SUBSTANTIATION: I n large open b u i l d i n g s ( i . e . , auditoriums, domes, theaters, warehouses, etc.) this arrangement is not practicable. Building can not be divided as this paragraph states ( i . e . , supermarkets, malls, large auto production type f a c i l i t i e s , etc.) . COMMITTEE ACTION: Accept in Principle.

Revise 2-5.2.1 to read: "Some buildings can . . . . "

COMMITTEE COMMENT: The Committee Action should sat isfy the Commenter's intent.

(Log #96) 92A - 73 - (2-5.2.4): Accept in Principle yUBMITTER: Edward J. Ward, Factory Mutual Research Corp. COMMENT ON PROPOSAL NO.: 92A-l RECOMMENDATION: Delete this entire paragraph. SUBSTANTIATION: Due to the limited l ikelihood of the smoke control system being ut i l ized, the heating problem should not be a consideration. We should not run the risk of minimizing the effectiveness of smoke control only because of heating requirements. ~OMMITTEE ACTION: Accept in Principle.

Replace 2-5.2.4 with a new 2-5.2.4 and 2-5.2.5 as follows and renumber TCR proposed 2 5.2.5 as 2-5.2.6:

2-5.2.4 When a f i r e occurs, a l l of the nonsmoke zones in the building may be pressurized as in Figures 2-5.2.1(a), (c) and (e). This system requires large quantities of outside air . The comments concerning location of supply a i r inlets of pressurized stairtowers (see 2-3.3) also apply to the Supply a i r inlets for nonsmoke zones.

2-5.2.5 In cold climates, the introduction of large quantities of outside a i r can cause serious damage to building systems. Therefore, serious consideration should be given to emergency preheat systems which w i l l temper the incoming a i r and avoid or l im i t damage. Alternatively, pressurizing only those zones imrnediateldy adjacent to the smoke zones could be used to l im i t the quantity of outside a i r required, as in Figures 2-5.2.1(b) and (d); however, the disadvantage of this limited approach is that i t is possible to have smoke flow through shafts past the pressurized zone and into unpressurized spaces. When this alternative is considered, a careful examination of the potential smoke flows involved needs to be accomplished and determined acceptable. COMMITTEE COMMENT: The Committee Action should sat is fy the Commenter's intent.

(Log #57) 9ZA - 74 - (2-5.2.5): Accept in Principle yVBMITTER: Gregory F. DeLuga, MCC Powers COMMENT ON PROPOSAL NO.: 92A-I RECOMMENDATION: Revise 2-5.2.5 as follows:

2-5.2.5 Zone alarms resulting from the operation of automatic f i r e detectors (such as smoke, heat, waterflow, etc.) of protective signaling systems, may be used as the basis For activating the appropriate zoned smoke control system(s). Such u t i l i za t i on of the protective signaling system requires that the alarm zones be arranged to coincide with the smoke control zones, to avoid activation of the wrong smoke control system(s). SUBSTANTIATION: The suggested revision incorporates correct protective signaling system terminology. COMMITTEE ACTION: Accept in Principle.

Revise 2-5.2.5 to read: 2-5.2.5 Fire signals from protective signaling

systems may be used For activating the appropriate zoned smoke control system(s). Such use of the protective signaling system requires that the alarm zones be arranged to coincide with the smoke control zones to avoid activation of the wrong smoke control system(s). COMMITTEE COMMENT: The revised Committee wording should sat isfy the Commenter's intent.

103

(Log #127) 92A - 75 - (2-5.2): Accept in Principle YUBMITTER: John G. Degenkolb, Carson City, NV COMMENT ON PROPOSAL NO.: 92A-I RECOMMENDATION: Revise as follows:

2-5.1 Smoke Control Zones. Smoke control zone boundaries should coincide with the sprinkler zones. When a sprinkler r iser can supply up to 52,000 sq Ft, the smoke zone should coincide and not overlap into another sprinkler zone. There may be more than one smoke zone in a single sprinkler zone but the smoke zone should not overlap the sprinkler zone. SUBSTANTIATION: Because the actuation of the smoke management equipment should be actuated by the sprinkler operation, (and smoke detection) automatically, i t would be improper For the sprinkler operation to set o f f the smoke management system in another area. COMMITTEE ACTION: Accept in Principle.

See Committee Action on Comment 92A-74 (Log #57) on 2-5.2.5. COMMITTEE COMMENT: The Committee Action on Log #57 should sat isfy the Commenter's intent.

(Log #4) 92A - 76 - (2-5.2.6 (New)): Reject yVBMITTER: Rick R. Schartel, Wyomissing Hi l ls , PA COMMENT ON PROPOSAL NO.: 92A-I RECOMMENDATION: Add paragraph 2-5.2.6:

2-5.2.6 Openings in return and exhaust a i r system ( i . e . , louvers, vents and g r i l l es ) shall be so located as to not draw f i r e and smoke toward exits. SUBSTANTIATION: Practical highrise f i r e Fighting experience has demonstrated that f i r e w i l l spread in these directions. This has occurred in center core buildings with central return and/or exhaust shafts and plenums. Since the Code does not require automatic suppression, the building must rely on Fire Fighting Forces for survival. The smoke control System should not make their job more d i f f i c u l t by drawing f i r e and smoke toward their attack points. COMMITTEE ACTION: Reject. COMMITTEE COMMENT: This is a general a i r conditioning issue which is outside the scope of this document. In other words, the Commenter's proposed wording addresses an area of the building which is inside the zone that has been given up with respect to other building zones which are to be kept tenable.

(Log #105) 92A - 77 - (2-5.2.6 (New)): Reject SUBMITTER: Francis J. McCabe, Prefco Products, Inc. COMMENT ON PROPOSAL NO.: 92A-l RECOMMENDATION: Add new paragraph:

2-5.2.6 I t is necessary to ident i fy and ver i fy the smoke zones with Fire heat From the smoke zones without f i r e heat. I t is dangerous to misidentiFy the f i r e zone -- lowering the pressure of the wrong zone which already has smoke migrating into i t could defeat smoke control and cause the f i r e to be drawn into that zone. Smoke detectors ident i fy; heat detection ver i f ies . SUBSTANTIATION: To this time we have weak requirements on possibly the most important control information bases For automatic system set-up. This guideline gap is one major reason behind Fire services objections to smoke systems. We must provide guidelines that call for the a l l important control information development that w i l l allow positive d i f fe rent ia t ion of smoke only f i l l e d vs. smoke and f i r e heat spaces. COMMITTEE ACTION: Reject. COMMITTEE COMMENT: The Commenter's wording would require both detection of smoke and detection of heat before activating the system. The Committee believes that ver i f ica t ion need not be required in every smoke control system.

(Log #128) 92A - 78 - (2-6): Reject yUBMITTER: John G. Oegenkolb, Carson City, NV COMMENT ON PROPOSAL NO.: 92A-I RECOMMENDATION: Revise as Follows:

2-6 Escalator Smoke Control. The Committee should take some action concerning the method or methods to be used to handle smoke control when escalators are

present. Many, many buildings are provided with escalators and there is a complete lack of coverage For that situation in the proposed Recommended Practice. SUBSTANTIATION: This is Far too important and complex a problem for one individual (myself) to resolve and is, in my opinion, one of the basics which the Committee should have considered. qOMMITTEE ACTION: Reject. COMMITTEE COMMENT: The Comment introduces material and concepts which have not had public review. The Commenter is encouraged to submit the material as public proposals following the publication of NFPA 92A when public proposals are once again being accepted.

(Log #136) 92A - 79 - (2-6): Accept in Principle SUBMITTER: C.V. Lovett, Easton, CT qOMMENT ON PROPOSAL NO.: 92A-I RECOMMENDATION: Revise as follows:

"In some buildings, there may . . . . " SUBSTANTIATION: Many buildings can not be zoned ( i . e . , autitoriums, domes, theaters, warehouses, etc.) plus many buildings do ~ot have stairtowers, so how can they be used/pressurized. Other examples of one ( I ) story buildings without stairtowers and that can not be zoned with walls ( i . e . , supermarkets, malls, department stores, large auto production type f a c i l i t i e s , etc.) . COMMITTEE ACTION: Accept in Principle.

In 2-6, as shown in the TCR, delete the First three words ( i . e . , "In many buildings") so as to read:

2-6 Combination Systems. There may be occasions

COMMITTEE COMMENT: The Committee Act ion should s a t i s f y the Commenter's i n t e n t .

(Log #58) 92A - 80 - (3-2.3.3): Accept in Principle SVBMITTER: Gregory F. DeLuga, MCC Powers qOMMENT ON PROPOSAL NO.: 92A-1 RECOMMENDATION: Rearrange 3-2.3.3 to read as follows:

3-2.3.3 Fan/Coil Units and Water Source Heat Pump Units. These types of a i r handling units are often located around the perimeter of a building f loor to condition the perimeter zones. Since the fan/coi l and water source heat pump units are comparatively small in outside a i r capacity and are typ ica l ly d i f f i c u l t to r e c o n f i g u r e For smoke con t ro l purposes, they may be excluded from per fo rming smoke c o n t r o l f u n c t i o n s . I f these units have outside a i r intake provisions, such units within the smoke zone should be shut down when the zone is to be negatively pressurized.

The fan/coil and water source heat pump units are typ ica l ly used in combination with larger central HVAC equipment or individual in ter ior zone a i r handling units. The zone smoke control funct ional i ty should be provided by the larger central or in ter ior zone a i r handling units. SUBSTANTIATION: The revision and rearrangement is suggested as an improvement on existing text. COMMITTEE ACTION: Accept in Principle.

Revise to read: 3-2.3.3 Fan/coil Units and Water Source Heat Pump

Units. These types of a i r handling units are often located around the perimeter of a building f loor to condition the perimeter zones. Since the fan/coi l and water source heat pump units are comparatively small in outside a i r capacity and are sometimes d i f f i c u l t to reconfigure for smoke control purposes, they should be excluded from performing smoke control functions. Units within the smoke zone should be shut down when the zone is to be negatively pressurized.

The fan/coi l and water source heat pump units are sometimes used in combination with larger central HVAC equipment or individual in ter ior zone a i r handling units. The zone smoke control functions should be provided by the larger central or in ter ior zone a i r handling units. qOMMITTEE COMMENT: The Committee Action should sat is fy the Commenter's intent.

(Log #59) 92A - 81 - (3-2.3.4): Accept in Principle SVBMITTER: Gregory F. DeLuga, MCC Powers COMMENT ON PROPOSAL NO.: 92A-I RECOMMENDATION: Revise 3-2.3.4, last two sentences as follows:

"Some induction units have cooling or heating coi ls to individual ly condition induced room a i r before mixing i t with primary a i r . Induction units within the smoke zone should be shut down or should have the primary a i r closed o f f when the zone is to be negatively pressurized." SUBSTANTIATION: The revision is suggested as an improvement on existing next. COMMITTEE ACTION: Accept in Principle.

Revise second paragraph of 3-2.3.4 to read: "Induction units within the smoke zone should be shut

down or should have the primary a i r closed o f f . COMMITTEE COMMENT: The Committee Action should sat isfy the Commenter's intent.

(Log #34) 92A - 82 - (3-2.3.5): Accept in Principle SUBMITTER: Rob Zivney, MCC Powers COMMENT ON PROPOSAL NO.: 92A-I RECOMMENDATION: Delete fourth paragraph and replace with:

"Smoke control may be achieved by supplying maximum supply a i r to areas adjacent to the smoke zone. For dual duct systems, this may be accomplished using only one deck. For the smoke zone, supply Fans would be shut o f f . " SUBSTANTIATION: More a c c u r a t e l y s t a t es what is i n c r e m e n t a l l y d i f f e r e n t about dual duct and mu l t i zone systems. COMMITTEE ACTION: Accept in Principle.

Replace the Fourth paragraph with the following: "Smoke control should be achieved by supplying

maximum ai r to areas adjacent to the smoke zone. This should be accomplished using the cold deck because i t is usually sized to handle larger a i r quantities. For the smoke zone, Supply Fans should be shut o f f . " COMMITTEE COMMENT: The emphasis should be to use the higher capacity part of the system. The Committee Action should sat isfy the Commenter's intent.

(Log #35) 92A - 83 - (3-2.3.6): Reject SUBMITTER: Rob Zivney, MCC Powers ~OMMENT ON PROPOSAL NO.: 92A-I RECOMMENDATION: Delete third sentence beginning "In the smoke...". In the Fourth sentence, delete "For smoke control, the VAV system Fan and terminal unit controls" and replace with "In the smoke control mode, the VAV system Fan and terminal unit controls serving smoke control zones adjacent to the smoke zone". At the end of the paragraph, add the sentence "In the smoke mode, the rAY system Fan serving the smoke zone and associated terminal unit fans may be shut down and dampers in those terminal units may remain in any posit ion." SUBSTANTIATION: This paragraph states that the bypasses exist to protect against ductwork damage. I t is not desirable to encourage this damage and impair the ab i l i t y of the smoke control system to function properly. Also, existing text provides no dist inct ion between the di f ferent control strategies For the smoke zone and adjacent smoke control zones. qOMMITTEE AqTION: Reject. COMMENT COMMENT: Because the recommended practice cal ls for boxes to be indexed open, there is no need to control the bypass.

(Log #36) 92A - 84 - (3-2.3.7): Accept SUBMITTER: Rob Zivney, MCC Powers COMMENT ON PROPOSAL NO.: 92A-I

I RECOMMENDATION: In First sentence delete "with". Delete the last sentence and replace with "In the smoke

I control mode, these terminal unit fans serving the smoke zone should be shut o f f . Terminal unit fans serving smoke control zones adjacent to the smoke zone may continue to operate normally."

104

SUBSTANTIATION: Deletion of "with" provides a more accurate statement. Current text provides no guidance. COMMITTEE ACTION: Accept.

(Log #60) 92A - 85 - (3-4.2.2): Accept SVBMITTER: Gregory F. DeLuga, MCC Powers COMMENT ON PROPOSAL NO.: 92A-I RECOMMENDATION: Revise 3-4.2.2 as follows:

3-4.2.2 Various types of control systems are commonly used for HVAC systems. These control systems u t i l i ze pneumatic, e lec t r ic , electronic, and programmable logic based control units. All of these control systems can be adapted to provide the necessary logic and control sequences to configure HVAC systems for smoke control. Programmable electronic logic ( i .e . microprocessor) based control units, which control and monitor HVAC systems as well as provide other building control and monitoring functions, are readily applicable for providing the necessary logic and control sequences for an HVAC system's smoke control mode of operation. ~IJ_BSTANTIATION: The suggested revision is offered as an improved version of the existing text. COMMITTEE ACTION: Accept.

(Log #129) 92A - 86 - (3-4.3): Accept in Principle SUBMITTER: John G. Degenkolb, Carson City, NV COMMENT ON PROPOSAL NO.: 92A-I RECOMMENDATION: Revise last sentence to read:

"Smoke control systems should be activated automatically and should also be capable of manual override." SUBSTANTIATION: I t is my opinion that the operation of the smoke management/control system should be accomplished automatically. The need for operation may most l i ke ly occur when there is no one present in the building to i n i t i a te action and even i f there were someone present, that person may not be aware of the problem unti l too late. COMMITTEE ACTION: Accept in Principle.

I Replace last sentence of 3-4.3 with: Smoke control systems should normally be activated

i automatically, however, under certain circumstances, I manual activation may be appropriate. Under either i automatic or manual activation, the smoke control

system should be capable of manual override. COMMITTEE COMMENT~ The Committee Action should sat is fy the Commenter's intent.

(Log #61) 92A - 87 - (3-4.3.1): Reject SUBMITTER: Gregory F. DeLuga, MCC Powers COMMENT ON PROPOSAL NO.: 92A-I RECOMMENDATION: Revise 3-4.3.1 as follows:

3-4.3.1 Automatic activation (or deactivation) includes al l means whereby a specific alarm From an automatic Fire detector of a protective signaling system causes activation of one or more smoke control systems without manual intervention. For purposes of automatic activation, "automatic f i r e detector" includes al l devices which require no manual action such as smoke, heat, and waterflow switches. SUBSTANTIATION: The suggested revision incorporates proper protective signaling system terminology. COMMITTEE ACTION: Reject. COMMITTEE COMMENT: The Committee believes that automatic activation need not necessarily come through the protective signaling system. I f the system were automatically activated, the Commenter's proposed wording would require a complete protective signaling system. This is not the Committee's intent. The present wording, as shown in the TCR, is adequate.

(Log #62) 92A - 88 - (3-4.3.2): Reject SUBMITTER: Gregory f . DeLuga, MCC Powers COMMENT ON PROPOSAL NO.: 92A-I RECOMMENDATION: Revise 3-4.3.2 as follows:

3-4.3.2 Manual activation (or deactivation) includes a l l means whereby an authorized person may activate smoke control by the use of controls provided for that purpose. Manual activation controls may be provided at one or more locations, including at a smoke control device ( i .e . at a fan, damper, etc . ) , on a local control panel, at a motor control ler , at the building's main control center, and at the f i r e f ighters smoke control station. The specific location(s) of manual activation controls should be as required by the authority having jur isdict ion. SUBSTANTIATION: The suggested revision is offered as an improved version of the existing text, and for terminology consistent with other paragraphs. COMMITTEE ACTION: Reject. COMMITTEE COMMENT: The present wording, as shown in the TCR, is adequate.

(Log #5) 92A - 89 - (3-4.3.2): Accept in Principle SUBMITTER: Rick R. Schartel, Wyomissing Hi l ls , PA COMMENT ON PROPOSAL NO.: 92A-I RECOMMENDATION: Add at end of paragraph 3-4.3.2:

"Manual pull stations which are part of the building's f i r e alarm system shall not be used for manual activation of smoke control systems." SUBSTANTIATION: Added text c l a r i f i es entire paragraph and prevents a well-intentioned mistake. COMMITTEE ACTION: Accept in Principle.

TO the end of 3-4.3.2 add: Manual Fire alarm pull stations should generally not

be used to activate smoke control systems, other than stairtower pressurization systems, because of the l ikelihood of a person signaling an alarm from a station outside the smoke zone of f i r e origin. COMMITTEE COMMENT: The Committee Action should sat is fy the Commenter's intent.

(Log #63) 92A - 90 - (3-4.3.3): Accept SUBMITTER: Gregory F. DeLuga, MCC Powers COMMENT ON PROPOSAL NO.: 92A-I RECOMMENDATION: Revise 3-4.3.3 as follows:

3-4.3.3 Response Time. Smoke control system activation should be in i t iated immediately af ter receipt of an appropriate automatic or manual activation command. Smoke control systems should activate individual components (dampers, fans, etc.) in the sequence necessary to prevent physical damage to the fans, dampers, ducts, and other equipment. The total response time for individual components to achieve their desired state or operational mode should not exceed the following time periods:

(a) Fan operation at the desired state . . . . . 60 seconds (b) Completion of damper travel . . . . . . . . . . 75 seconds.

SUBSTANTIATION: The suggested revision is offered as an improved version of the existing text. COMMITTEE ACTION: Accept.

(Log #64) 92A - 91 - (3-4.3.4(a)): Reject SUBMITTER: Gregory F. DeLuga, MCC Powers COMMENT ON PROPOSAL NO.: 92A-1 RECOMMENDATION: Revise 3-4.3.4(a) as follows:

(a) When required, a Fire f ighters smoke control station (FSCS) should provide f u l l monitoring and manual control of a l l smoke control systems and equipment from a designated location. SUBSTANTIATION: The revision is Suggested as an improvement of the existing text. COMMITTEE ACTION: Reject. COMMITTEE COMMENT: The Commenter's wording would require monitoring and reporting of the condition of every damper. Such detail is not always needed.

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(Log #106) 92A - 92 - (3-4.3.41: Accept in Principle SUBMITTER: Francis J. McCabe, Prefco Products, Inc. COMMENT ON PROPOSAL NO.: 92A-I RECOMMENDATION: Revise as follows:

3-4.3.4(b1 . . . . e lectr ic disconnect switches, high l im i t static pressure switches, and combination fire/smoke damper closure control that would preclude that response to heat beyond the required UL33 Fire l ink or UL555S operator/actuator ratings. SUBSTANTIATION: There has been incomplete comrnunication between f i r e f ighters and Fire damper manufacturers. This has resulted in the manufacturers offer ing a Fire damper override control From the FSCS. The overriding reaction to complete communications on this is that the f i r e damper function in elevated temperatures that exceed the f i r e closure response rating must be intact and not l e f t incapacitated or beyond the operating test rating of UL33 or UL555S. See New York Fire Department l e t t e r appended. This f i r e damper closure and barr ier system fa i lu re would be a serious detriment to the success of smoke control systems. (Note: A copy of the referenced material is available For review at NFPA Headquaters.) COMMITTEE ACTION: Accept in Principle.

Revise the end of 3-4.3.4(b1 to read: • . . electr ic disconnect switches, high l im i t stat ic

pressure switches, and combination Fire/smoke damper closure control that would preclude that response to heat beyond the required UL 33, Heat Responsive Links For Fire-Protection Service, heat responsive l ink or UL 555S, Leakage Rated Dampers For Use in Smoke Control Systems, operator/actuator degradation temperature classif icat ions.

Add a Chapter 5 of Referenced Publications to include UL 33 and UL 555S. COMMITTEE COMMENT: The Committee Action should sat isfy the Commenter's intent.

(Log #65) 92A - 93 - (3-4.3.4(b) and (c i ) : Accept ~n Principle SUBMITTER: Gregory F. DeLuga, MCC Powers COMMENT ON PROPOSAL NO.: 92A-l RECOMMENDATION: Revise 3-4.3.4(b) and 3-4.3.4(c) into paragraph 3-4.3.4(b) as follows:

The FSCS should have the highest p r i o r i t y control over a l l smoke control systems and equipment. Where manual controls are also provided at other building locations for control of smoke control systems, the control mode selected From the FSCS should prevail. FSCS control should override or bypass other building controls such as Hand-OFf-Auto, and Start/Stop switches located on Fan motor control lers, freeze detection devices, and duct smoke detectors. FSCS control should not override or bypass devices and controls which are intended to protect against e lectr ical overloads, provide For personnel safety, and prevent major system damage. These include overcurrent protection devices, electr ical disconnect switches, and devices which protect HVAC systems against stat ic pressure extremes which could cause the rupture or collapse of ducts.

Exception: The FSCS Fan control capabi l i ty need not bypass switches located on motor control lers of nondedicated smoke control system Fans, when:

(1) Such fan motor control lers are located in mechanical or electr ical equipment rooms, or other areas generally accessible only to authorized personnel, and

I (21 The use of such a motor contro l ler switch to • turn a fan on or o f f w i l l ult imately cause a trouble

annunciation at the building's main control center. SUBSTANTIATION: This revision is suggested as an improved combination of existing paragraphs (b) and (c), and also provides a practical al ternative to requiring complicated and expensive bypass control For nondedicated smoke control system Fan motor control ler switches. COMMITTEE ACTION: Accept in Principle.

I Do as the Commenter suggests but at the end of the long raragraph, before the exception, delete most of

I the last two lines so as to read: ". . . These include overcurrent protection devices

and electr ical disconnect switches• Exception: The FSCS Fan . . . ".

COMMITTEE COMMENT: The Committee Action should sat isfy the Commenter's intent.

(Log #66) 92A - 94 - (3-4.3.4(d) and (e)): Accept yUBMITTER: Gregory F. DeLuga, HCC Powers COMMENT ON PROPOSAL NO.: 92A-I RECOMMENDATION: Revise 3-4.3.4(d) and (el as follows:

(d) The f i r e Fighters smoke control station should contain a building diagram which clear ly indicates the type and location of a l l smoke control equipment (fans, dampers, etc.) . The building areas affected by the equipment should also be clearly indicated.

(e) The actual status of the systems and equipment which are activated or are capable of activation For smoke control, should be clearly indicated at the Fire f ighters smoke control station. SUBSTANTIATION: The revision is proposed as an improvement of the existing text. COMMITTEE ACTION: Accept.

(Log #24) 92A - 95 - (3-4.3.4(g)-(New)): Reject $UBMITTER: James R. Thiel, Underwriters Laboratories Inc. COMMENT ON PROPOSAL NO.: 92A-I RECOMMENDATION: Expand Paragraph 3-4.3.4 as Follows:

3-4.3.4 Fire Fighters Smoke Control Station. (g) Smoke control systems may employ dedicated or

nondedicated functions, or both, as described in Section 2-1.2. System commands issued in dedicated systems (functions) should be monitored For in tegr i ty by means of end-to-end ver i f icat ion, i . e . , feedback that the command has been received and executed• The system should also employ an automatic weekly test of the various dedicated smoke control functions• Audible annunciation of Function Failure should be given.

System commands issued in nondedicated systems (functions) should also require end-to-end ver i f i ca t ion. I t is acceptable to test funct ional i ty by manual means; and either audible or visual indication of function Failure should be provided. SUBSTANTIATION: Proposed NFPA 92A recognizes that component fa i lures in dedicated systems may be undetected since they generally do not affect building operation; nondedicated systems, on the other hand, have the advantage of using common building HVAC components which are Frequently used, hence Failures are more readily detected.

Proposed expansion of Paragraph 3-4.3.4 which is based on Section 2-1.2 recognizes this dist inct ion and recommends an industy-accepted Form of command signal monitoring which is cost effect ive and rel iable• The proposal For automatic weekly testing of dedicated systems supplements end-to-end ver i f icat ion; i t is needed from the standpoint of theoret ical ly maintaining a reasonable degree of confidence (roughly 90 percent) that the system w i l l remain in good working condition.

While end-to-end ver i f ica t ion of commands is also important in nondedicated systems, manual testing ~s suf f ic ient to supplement system components which are Frequently used. COMMITTEE ACTION: Reject. COMMITTEE COMMENT: The Committee believes that the Commenter's wording would add supervision levels in excess of those deemed necessary.

(Log #67) 92A - 96 - (3-4.41: Accept SUBMITTER: Gregory F. DeLuga, MCC Powers COMMENT ON PROPOSAL NO.: 92A-I RECOMMENDATION: Add:

"3-4.4 Controls For Stair Pressurization Systems." as a header l ine. Change present 3-4.4 to 3-4.4.1. SUBSTANTIATION: This suggestion is made to establish consistency of style with 3-4.5 Controls for Zoned Smoke Control Systems. COMMITTEE ACTION: Accept,

(Log #110) 92A - 97 - (3-4.5(a)( I ) ) : Accept in Principle YUBMITTER: Elmer Chapman, Levittown, NY COMMENT ON PROPOSAL NO.: 92A-I RECOMMENDATION: In 3-4.5(a)(I), and in any other applicable paragraphs, state that automatic actuation of a zoned smoke control system, which w i l l attempt to exhaust the Fire area and supply a i r to other areas,

106 shall not be undertaken under any circumstances.

SUBSTANTIATION: Fully Automated Smoke Control Systems Can Be Hazardous

Automatic exhausting of the Fire area does not consider the negative effects such a i r movement w i l l have on the Fire area. The use of f u l l y automated zone smoke control systems can be hazardous. Actual Fire experience has proven this to be true. Three actual cases w i l l be described.

Exhausting the Fire Floor Fully automated smoke control systems do not take

into account the dynamics of the f i r e and therefore can create hazardous conditions in a Fire building. They violate two basic principles of Firefighting. Which are:

First Principle Venti lation of a Fire building is not conducted unt i l

the Fire Department has i ts hose lines in place and there is water in the hose lines for suppression of the f i r e . The Fire Service is Familiar with the person throwing a brick through the window of a f i r e building while awaiting the arr ival of the Fire Department. They reason that while waiting for the Fire Department they may as well help assist the Firemen by breaking the windows as they believe that this w i l l be the First action the firemen take upon their a r r i va l . They are wrong. The Fire Department does not venti late a f i r e building unt i l i t has i ts hose lines in place and supplied with water to control the Fire. Similarly any automated zone smoke control system that proposes to exhaust the f i r e f loor area (venti late a Fire) can be just as wrong. Activating a zoned smoke control system prior to the application of a suppressant is equally as wrong. Therefore automatic activation of a zoned smoke control System, cannot be advocated unless the building is Fully sprinklered. This should be clear ly stated in the text of NFPA 92A.

Second Principle When vent i lat ion is conducted at a f i r e , the

vent i lat ion is provided d i rect ly over the main body of f i r e . I f this principle is violated the f i r e w i l l be spread From i ts present location towards the point of vent i lat ion. Therefore, in a zoned smoke control system this means that you cannot exhaust the Fire Floor through the plenum. This also applies to sprinklered buildings because i f the plenum is used for exhaust i t w i l l pull the Fire through the plenum above the sprinklers and possibly overwhelm the sprinkler system. I f however the plenum is sprinklered i t may be used in the exhausting of the Fire Floor.

The EFfects of Automatic Exhaust Upon Fires Fire at 1 New York Plaza

A Fire at I New York Plaza on August 5, 1970 originated in the plenum on the 33rd Floor d i rec t ly under the telephone equipment room on the 34th Floor. Fire was drawn through the plenum in a westerly direction to the return a i r shaft 200 feet away from the point of origin. The f i r e was prevented from traveling in the opposite direction by a Floor to slab part i t ion. The HVAC system in this building was designed to exhaust smoke from the f i r e Floor. When the smoke detector in the return a i r shaft was activated i t only shut down the supply Fans and l e f t the return Fans running. This is permitted under NFPA 90A and was permitted by New York City RS 13 in effect at the time. This automatic exhaust system was planned to exhaust any smoke From a Fire. I t did not Function as planned as i t was overwhelmed by the amount of smoke that the Fire generated. I t had a very serious effect upon the f i r e i t se l f . I t spread the Fire 200 feet From the point of origin to the v i c in i t y of the return a i r shaft, where a l l the major structural damage was done. The d i f fe rent ia l of pressure between the Fire area and the return a i r shaft caused the wall separating the Fire area from the return a i r shaft to collapse into the return a i r shaft.

This provision for exhausting the f i r e Floor has been removed From the New York City Code and should be removed From NFPA 90A. This is one example of what can happen when an attempt is made to use the HVAC system to exhaust the f i r e f loor. In this case the HVAC system was exhausting many Floors and not only the f i r e Floor. The exhaust rate was six a i r changes per hour. The ef fect of the exhaust fans was not as great as would be expected in a smoke control system where the exhaust Fans are used to exhaust the Fire Floor exclusively.

Fire at 810 7th Avenue A f i r e at 810 7th Ave. on Jan. 17, 1974 started in a

dumpster in the elevator lobby on the 5th Floor, The HVAC system was also arranged to have the return Fans remain on to exhaust the smoke from a Fire. The Fire entered the plenum of the elevator lobby and was pulled through the plenum to the return a i r shaft. As this f i r e roared through the plenum i t heated the noncombustible ceil ing t i l e to incandescence unti l they f e l l out of their frames, starting many Fires throughout the Floor. At this f i r e the Fire Department extinguished the f i r e and preserved the evidence of this phenomenon. How many other Fires did this happen? But the spot Fires grew unti l the area was completely involved in one large Fire and the evidence destroyed. This example demonstrates the hazards of automated exhausting of the Fire f loor and of exhausting through the plenum. The exhaust rate was again six a i r changes per hour.

Fire at 777 3rd Avenue A f i r e at 777 3rd Av. on Jan. 9, 1976 started some

time af ter midnight on the 20th Floor. The HVAC system was completely shut down For the night. When the building engineer arrived shortly af ter 6 a.m., he went to the 40th f loor mechanical equipment room (MER) where he Found a smoke condition on the upper Floors. He immediately called the Fire Department. The Fire Department searched the building for over an hour. The location of the f i r e had not been located and the smoke condition on the 17th to the 40th Floors was increasing. I t was decided to turn the exhaust fans on to remove the smoke From the building. When this was done 5 windows on the 20th Floor blew out and a large area of the Floor was involved in Fire. The f loor area was about 200 f t by lO0. The f i r e area was about 7000 sq Ft. The HVAC zone was the 17th to the 38th Floor. Again exhausting the f i r e f loor had a disastrous ef fect upon the Fire. Again the exhaust rate applied to the Fire f loor was only six a i r changes per hour. This f i r e had been burning for many hours with the HVAC system shut o f f . The growth rate of the f i r e with the HVAC system o f f was very slow and was in a smoldering state. When an attempt was made to exhaust the f i r e area at a rate of six a i r changes per hour the entire Fire area was involved in Fire in less than one minute. 92A does not address what exhaust rate is to be used on the Fire area. Any attempt to exhaust the Fire area w i l l create a i r movement in this area which can cause disastrous results as shown by the three actual Fires related above.

All automated operations are not hazardous. Automatic shut down of a l l supply and return Fans, and the closing of a l l supply and return dampers throughout the building can safely be accomplished and in Fact is highly recommended. This can be accomplished by the actuation of any device indicating the existence of a Fire in a building including smoke detectors. The automatic actuation of a s ta i r pressurization system can also be actuated by any device in the building that indicates the existence of a f i r e in a building. Automatic actuation of a zoned smoke control system which w i l l attempt to exhaust the f i r e area and supply a i r to other areas shall not be under taken under any circumstances. The consequences of such an action can be too hazardous. COMMITTEE ACTION: Accept in Principle.

Add to the end of 3-4.5.1(a)(I) the Following separate paragraph:

Automatic actuation of a zoned smoke control system, which is designed to exhaust the f i r e area and supply a i r to other areas, should be given careful consideration before being undertaken because of the possib i l i ty of activation of a detector outside the zone of Fire origin. COMMITTEE COMMENT: The Committee Action should sat is fy the CommenteF's intent.

107

(Log #6B) 92A - 98 - (3-4.4(a)): Reject SUBMITTER: Gregory F. DeLuga, MCC Powers qOMMENT ON PROPOSAL NO.: 92A-I RECOMMENDATION: Revise the First sentence of 3-4.4(a) Automatic Activation to read as Follows:

(a) Automatic Activation. The occurrence of any f i r e alarm signal From both manual and automatic devices connected to the building's protective signaling system should cause an automatic activation of a l l s ta i r pressurization system.

SUBSTANTIATION: This revision is suggested to incorporate proper terminology into the existing text. COMMITTEE ACTION: Reject. GOMMITTEE COMMENT: The Commenter's proposed wording does not improve or c l a r i f y . The present terminology, as shown in the TCR, is proper.

(Log #69) 92A - 99 - (3-4.4(b)): Accept $UBMITTER: Gregory F. DeLuga, MCC Powers ~OMMENT ON PROPOSAL NO.: 92A-I RECOMMENDATION: Revise 3-4.4(b) Manual Activation to read as follows:

(b) Manual Activation. Manual activation and deactivation control capabil i ty over the s ta i r pressurization systems should be provided at the FSCS as well as at the building's control center. In addition, the PSCS should have the capabil i ty to override the automatic shutdown of a s ta i r pressurization fan upon smoke detection, in accordance with proper judgement of the best course of action. SUBSTANTIATION: The revision is proposed as a more comprehensive treatment of the subject. COMMITTEE ACTION: Accept.

(Log #I09) 92A - I00 - (3-4.S. l (a)(1)) : Reject SUBMITTER: Elmer Chapman, Levittown, NY COMMENT ON PROPOSAL NO.: 92A-l RECOMMENDATION: In 3-4.5.1(a)(I) and other related paragraphs, delete reference to a smoke detector as an acceptable means of automatically in i t i a t ing a smoke c o n t r o l system, SUBSTANTIATION: Smoke de tec to rs cannot be r e l i e d upon to de f i ne the f i r e area. The r e l i a b i l i t y o f smoke detectors to perform this function has not been satisfactory demonstrated. In fact the opposite has been demonstrated in New York City where the false alarm rate is estimated to be in excess of I000 to I. Many systems are being shut down to prevent the systems From false alarming and disrupting business. The deficiency in the r e l i a b i l i t y factor of smoke detectors prohibits them from being used as a means of activation of an automatic zoned smoke control system. I f a smoke detector should define the wrong area as the f i r e area and activate a zoned smoke control system based on this false information, the results could be disastrous. As an example of false smoke detector information, the Fire in the Westchase Hilton in Houston, Texas on March 6, 1986 was on the fourth f loor, but the f i r s t smoke detector to activate was on the eighth Floor.

Let us For a minute look at a hypothetical case and analyze the effects on a f i r e that would occur i f a smoke detector defined the wrong f loor as the Fire f loor . In this hypothetical case a smoke detector activated the automated zone smoke control system and misdefined the Fire f loor by one f loor, a highly possible scenario. The real Fire is on the 19th Floor but the f i r s t smoke detector to activate is on the f loor above, the 20th Floor. Air would be supplied by the automated zone smoke control system to the 19th f loor , the real f i r e f loor , intensifying the f i r e on that f loor . Air would be exhausted by the automated zone smoke control system from the 20th Floor, the false Fire f loor , creating a negative effect on that f loor . The Spread of the f i r e from the 19th f loor to the 2Oth f loor would be greatly assisted by this d i f fe rent ia l of pressure created by the automated zone smoke control system. When two f loors of a high-rise building are f u l l y involved in Fire we have reached the l imi ts of manual f i r e suppression. I t is l i ke l y that the f i r e w i l l then spread to a l l f loors above the Fire Floor unti l i t reaches the roof.

Advocacy for the insta l la t ion OF such a automated zoned smoke control system using smoke detectors as the in i t i a t i ng device is wrought with dangers. A system of greater r e l i a b i l i t y must be used to determine the real f i r e f loor. Such a system is the water Flow in a sprinkler system. COMMITTEE ACTION: Reject. COMMITTEE COMMENT: Automatic operation by smoke detection is appropriate with the necessary caution. See the Committee Action on Comment 92A-97 (Log #1tO) on 3-4.5(a)(I).

108

(Log #70) 92A - IOl - (3-4.5.1(a)( I ) ) : Accept in Principle SUBMITTER: Gregory F. DeLuga, MCC Powers COMMENT ON PROPOSAL NO.: 92A-I RECOMMENDATION: Revise 3-4.5.1(a)(1)as follows:

(1) An automatic smoke detection system may be used to automatically activate a zoned smoke control system. The smoke detection system may be o£ limited coverage (less than the usually accepted 900 sq Ft per detector), provided that the smoke detectors are located so as to detect smoke before i t leaves the smoke zone. The location of smoke detectors and the zoning of the detectors needs to be careful ly analyzed to achieve a smoke detection system which w i l l re l lab ly indicate the correct smoke zone. SUBSTANTIATION: This proposal is suggested as an alternate way of expressing the concept OF using a limited coverage smoke detection system to automatically activate zoned smoke control. The references to "smoke leaving the smoke zone", and "suf f ic ient quantities" have been removed due to the inab i l i t y of present day smoke detectors to indicate "quantity" or the "direction" of smoke travel. COMMITTEE ACTION: Accept in Principle.

Do as the Commenter Suggests but reword the Commenter's second sentence to read:

"The smoke detection system may be of limited coverage having spacing greater than 900 sq Ft per detector provided that the smoke detector . . " ~OMMITTEE COMMENT: The Committee Action should sat is fy the Commenter's intent.

(Log #I03) 92A - 102 - (3-4.5.1(a)( I ) ) : Reject SUBMITTER: H. Brooke Stauffer, NEMA COMMENT ON PROPOSAL NO.: 92A-I RECOMMENDATION: Delete the last 3 sentences. Add the Following as a third sentence:

"Application of automatic smoke detection may be found in NFPA 72E, Standard For Automatic Fire Detectors, Chapter 9." SUBSTANTIATION: Information is located in existing NEMA Standards covering this application. Chapter 9, NFPA 72E is Smoke Detectors For Control of Smoke Spread. (NOTE: See NFPA IM, Style Manual, For information pertaining tO the reference of other documents.) COMMITTEE ACTION: Reject. COMMITTEE COMMENT: Reference to NFPA 72E does appear in the document. The Committee believes that the existing wording is appropriate.

(Log #22) 92A - I03 - (3-4.5.1): Accept in Principle SUBMITTER: Gunnar Heskestad, Factory Mutual Research Corp. COMMENT ON PROPOSAL NO.: 92A-I RECOMMENDATION: Under (a), delete Paragraph (1) and revise paragraph (2) to read:

"A waterflow switch, heat detector or smoke detectlon system serving the smoke zone should be used to activate zoned smoke control systems." ~UBSTANTIATION: Detection of "smoke leaving the smoke zone", as presently recommended in (1), would normally Occur at a very advanced f i r e stage. COMMITTEE ACTION: Accept in Principle.

See Committee Action on Comment 92A-lOl (Log #70) on 3-4.5.1(a)( l) . COMMITTEE COMMENT: The subject of "smoke leaving the smoke zone" has been addressed by Log #70. The Committee Action should sat isfy the Commenter's intent.

(Log #97) 92A - tO4 - (3-4.5.1): Accept in Principle SUBMITTER: Edward a. Ward, Factory Mutual Research Corp. COMMENT ON PROPOSAL NO.: 92A-I RECOMMENDATION: Under "Automatic Activation", Subpart ( l ) , revise f i r s t sentence to read as Follows:

"An automatic detection system designed to detect smoke in the smoke zone..." SUBSTANTIATION: Paragraph as written w i l l result in needless time delay. I f concern is false signals, the r e l i a b i l i t y of the detectors should be examined, not the r e l i a b i l i t y of the smoke control System.

COMMITTEE AGTION: Accept in Principle. See Committee Action on Comment 92A-101 (Log #70) on

3 - ¢ . 5 . 1 ( a ) ( 1 ) . COMMITTEE COMMENT: The Committee Ac t i on on Log #70 should sat isfy the Commenter's intent.

(Log #71) 92A - 105 - (3-4.5.1(b)(2)): Accept in Principle SUBMITTER: Gregory F. DeLuga, MCC Powers COMMENT ON PROPOSAL NO.: 92A-l RECOMMENDATION: Revise 3-4.5.1(b)(2) as follows:

(2) Key operated manual switches which are located within a smoke zone and which are clearly marked to ident i fy their function, may be used to manually activate the zone's smoke control system. When a FSCS is provided, zoned smoke control systems should also be able to be manually activated from the FSCS, by switches which are c lear ly marked to ident i fy the zone and function. In addition, when the building is provided with a main control center, zoned smoke control systems should also be able to be manually activated from the building's main control center. SUBSTANTIATION: The proposed revision addresses the need to manually activate zoned smoke control systems from a FSCS as well as the building's main control center. This enables f i r e service and knowledgeable building personnel to activate smoke control systems without the need to travel to the smoke zone. COMMITTEE ACTION: Accept in Principle.

Do as the Commenter suggeStS, but also retain the Note which appears in the TCR. COMMITTEE COMMENT: The Committee Action should sat isfy the Commenter's intent.

(Log #72) 92A - 106 - (3-4.5.2(b)): Accept SUBMITTER: Gregory F. DeLuga, HCC Powers COMMENT ON PROPOSAL NO.: 92A-l RECOMMENDATION: Revise 3-4.5.2(b) as follows:

(b) Manual Activation and Deactivatlon. Manual activation or deactivation of zoned smoke control systems and equipment should have p r io r i t y over automatic activation of smoke control systems and equipment, as well as over a l l other sources of automatic control within the building. Where equipment used for zoned smoke control is subject to automatic activation in response to an alarm from an automatic f i r e detector of a protective signaling system, or where such equipment is subject to automatic control according to building occupancy schedules, energy management strategies, or other nonemergency purposes, such automatic control should be preempted or overridden by manual activation or deactivation of the smoke control equipment. Manual controls provided speci f ica l ly For this purpose should be clear ly marked as to the zone and Function served. Manual controls which are shared For both smoke control functions and other building control purposes, as in a building's main control center, should f u l l y cover the smoke control Functionality in the control center operational documentation. SUBSTANTIATION: This proposed revision incorporates terminology which is consistent with previous paragraphs ( i .e . activation in l ieu of operation), and also more thoroughly addresses the requirements For properly identifying the manual controls. qOMMITTEE AqTION: Accept.

(Log # l l ] ) 92A - I07 - (3-4.5.2): Reject $UBMITTER: Elmer Chapman, Levittown, NY qOMMENT ON PROPOSAL N~=: 92A-I REqOMMENDATION: In 3-4.5.2, and in any related paragraphs, state that Fire dampers should not be overridden by the F i re f ighter 's Central Smoke Station. SUBSTANTIATION: Fire dampers should not be overridden by the Firef ighter 's Central Smoke Station. This action would violate the effectiveness of a l l "Fire Barriers" in a building with zoned smoke control. Buildings are divided into f i r e areas by rated f i r e barriers. These barriers may consist of f i r e part i t ions, f i r e walls, cei l ings, f loors, etc. The purpose of these f i r e barriers is to l im i t the size of a f i r e by preventing the spread of f i r e to adjacent areas. Any openings in these f i r e barriers must be protected with rated assemblies to prevent the spread of f i r e . Protective assemblies may consist of f i r e 109

rated doors or, in HVAC systems, f i f e rated f i r e dampers. I f an opening is permitted in a f i r e barrier i t w i l l render the barrier inef fect ive. I t w i l l permit the spread of f i r e beyond the area of origin. The openings in these f i r e barriers which are permitted For the operation of a HVAC System are protected by Fire dampers. Fire dampers are required by code to close when a temperature at the damper reaches 60 ° F above the maximum temperature that can be expected under normal operations. I f this temperature is exceeded the dampers w i l l close thus preventing the spread of Fire through this opening in the Fire barr ier. Once these dampers close they cannot be reopened remotely. TO reopen these dampers i t is necessary to go d i rect ly to the damper and reopen the damper manually and replace the thermostatic device (fusible l ink) to malntain the damper in an opened condition. When this type Fire damper closes, i t renders this opening useless in a smoke control system unti l such time that the Fire Department can get to the location of the Fire damper and manually open i t . This is unsatisfactory when i t is expected that the HVAC system w i l l be used as a smoke control system or as a smoke removal system. A damper that can be remotely controlled From the Firef ighters's Central Smoke Station is more desirable but this damper must also f u l f i l l the original function that was required of i t , stop the spread of f i r e through this opening. This damper must meet a l l the requirements of UL555.

A f i r e damper is a very inef fect ive smoke stop damper as i t has a very high smoke leakage rate. Also a Fire damper w i l l not close when the temperature of the smoke is less that the setting of the thermostatic device at the damper permitting the spread of smoke throughout the building by the HVAC system. A smoke damper must be set to close by the actuation of a smoke detector i f i t is expected to prevent the spread of smoke. A smoke damper should meet the requirements of ULS55S. A combination of a f i r e and smoke damper may be used where both are required but the combination damper must meet the requirements of both UL555 and UL555S. This combination damper may be a controllable damper but the Fire stopping Function must not be overridden by the signal from the Firef ighter 's Central Smoke Station. The damper must close at the required temperature regardless of the signal being sent From the control panel. When the temperature at the damper has returned to a safe temperature that w i l l not permit the spread of f i r e than control of the damper may be returned to the control panel. An improperly designed and or operated f i r e damper can create a greater f i r e hazard and l i f e safety hazard than i f no smoke control system had existed.

These are my objections to the document as presently written. These objections are legitimate and modifications in the document to bring these conditions to the attention the user w i l l result in an improved document that w i l l provide a f i r e safe environment For a l l concerned. COMMITTEE ACTION: Reject. COMMITTEE COMMENT: The Commenter's wording would exclude a possible viable operational mode. Additionally, see the Committee Action on Comment 92A-92 (Log #106) on 3-4.3.4 which addresses a similar subject.

(Log #73) 92A - I08 - (3-4.5.3): Reject SUBMITTER: Gregory F. OeLuga, MCC Powers COMMENT ON PROPOSAL NO.: 92A-I RECOMMENDATION: Revise 3-4.5.3, Sequence, as Follows:

3-4.5.3 Sequence. The activation or deactivation of smoke control systems, should occur in a careful ly designed overall sequence, to ensure maximum benefit and prevent any damage or undesirable effects on ducts and other equipment. SUBSTANTIATION: This revision is proposed as an improvement over the existing text, as well as incorporating the concept of properly deactivating a smoke control system. Consideration must be given to the proper sequence For both activation and deactivation. ~OMMITTEE ACTION: Reject. qOMMITTEE COMMENT: The existing wording adequately covers the Committee's intent.

(Log #37) 92A - I09 - (3-4.5.4): Reject SUBMITTER: Rob Zivney, MCC Powers COMMENT ON PROPOSAL NO.: 92A-l RECOMMENDATION: In the f i r s t sentence af ter "format which", insert "establishes required outputs and associated inputs, and".

Revise paragraph (a) as follows: "Outputs from a protective signaling system which are

the inputs to the smoke control system. Care should be taken to ensure that the zoning of the protective signaling system is consistent with the zoning of the smoke control system. Typically, the zoning of the protective signaling system should be f inal ized af ter the smoke control zones are established, to ensure that protective signaling system zones which activate the smoke control system do not cover multiple smoke control zones. This may involve adding additional zones to the protective signaling system."

In paragraphs (c) and (d) insert "allowable" af ter "maximum". In paragraph ( f ) , delete "the" and "system".

Revise paragraph ( i ) as follows: "Auxi l iary functions as may be required, to achieve or maximize the ef fect of the smoke control system. Changes to, as well as the override of normal operation stat ic pressure control setpoints should also be indicated i f applicable."

Add new paragraph ( j ) "Equipment which is to be controlled from or have i ts status indicated on the FSCS ( i f provided)." SUBSTANTIATION: Provides better guidance on the subject. COMMITTEE ACTION: Reject. COMMITTEE COMMENT: Existing guidance, per TCR draf t , adequately covers the Committee's intent.

(Log #38) 92A - 1]0 - (3-4.5.5): Accept SUBMITTER: Rob Zivney, MCC Powers COMMENT ON PROPOSAL NO.: 92A-I

I RECOMMENDATION: Relocate "automatic" to fol low "the system should continue". SUBSTANTIATION: Makes the paragraph consistent with the heading. COMMITTEE ACTION: Accept.

(Log #74) 92A - I l l - (3-4.5.5): Reject SUBMITTER: Gregory F. DeLuga, MCC Powers COMMENT ON PROPOSAL NO.: 92A-I RECOMMENDATION: Revise 3-4.5.5 as follows:

3-4.5.5 Automatic Activation in Response to Multiple Alarm Signals.

In the event that multiple alarm signals are received, indicating f i r e or smoke in more than one zone, the smoke control system(s) should continue to operate as automatically activated in response to the f i r s t alarm signal received. SUBSTANTIATION: The proposed revision incorporates proper signaling system terminology. COMMITTEE ACTION: Reject. COMMITTEE COMMENT: The TCR verbiage, as revised by the Committee Action on Comment 92A-llO (Log #38) better explains the concept.

(Log #6) 92A - ]12 - (3-4.5.5): Reject SUBMITTER: Rick R. Schartel, Wyomissing H i l l s , PA COMMENT ON PROPOSAL NO.: 92A-I RECOMMENDATION: Revise paragraph to read as fol lows:

"In the event that automatic signals are received from more than one smoke zone, a l l functions required as i f i t were the i n i t i a l signal shall occur except that zones under negative pressure from the f i r s t signal shall continue in that mode." SUBSTANTIATION: By posit ively pressurizing a second f i r e (not an uncommon event, par t icu lar ly during arson) the Fire may be accelerated creating a worse condition.

COMMITTEE ACTION: Reject. COMMITTEE COMMENT: The Committee feels that the state of the art is such that human analysis is needed before activation of smoke control to a second area.

(Log #8) 92A - If3 - (3-6.3(New)): Accept in Principle SUBMITTER: J. Brooks Semple, Smoke/Fire Risk Management, Inc. COMMENT ON PROPOSAL NO.: 92A-l RECOMMENDATION: Add new section to read:

3-6.3 Elevated temperatures may be expected in the smoke exhaust path, often suf f ic ient to exceed Class ] duct material temperature l imi ts. However, i f uninsulated metallic or masonry duct materials are used, they w i l l provide suf f ic ient heat-sink capacity to lower smoke temperatures before reaching the Fans. Therefore, except in the unusual circumstances of high combustible fuel loading very near to the exhaust fans, special high temperature ratings of smoke exhaust fans should not be necessary. See 2-5.2.3. SUBSTANTIATION: Costly, high temperature rated fans are often specified when their remote locations from fuel loads and the heat-sink capacity of the connecting ducts are overlooked. The same l ine of reasoning prevents the use of normal HVAC fans for smoke control, thus either unnecessarily raising the price of the insta l la t ion or maybe pricing smoke control out of the job. COMMITTEE ACTION: Accept in Principle.

Add a 3-6.3 to read: 3-6.3 Special high temperature ratings for smoke

exhaust fans w i l l not normally be necessary. COMMITTEE COMMENT: The Committee Action should sat is fy the Commenter's intent.

(Log #75) 92A - ]14 - (3-7.2): Reject SUBMITTER: Gregory F. DeLuga, MCC Powers COMMENT ON PROPOSAL NO.: 9ZA-I RECOMMENDATION: Revise 3-7.2 as Follows:

3-7.2 Normal electr ical u t i l i t y power which serves the HVAC systems, and has generally provided re l iable service is acceptable for nondedicated zone smoke control systems. SUBSTANTIATION: The revision is suggested as an improved version of the present text. COMMITTEE ACTION: Reject. COMMITTEE COMMENT: The Committee Feels that the existing verbiage, as shown in the TCR, is adequate.

(Log #98) 92A - 115 - (3-7.2): Reject SUBMITTER: Edward J. Ward, Factory Mutual Research Corp. COMMENT ON PROPOSAL NO.: 92A-l RECOMMENDATION: Delete 3-7.2. SUBSTANTIATION: The importance of smoke control and power supply to i t should be independent of whether or not system is dedicated or nondedicated. Stand-by power is needed for either. COMMITTEE ACTION: Reject. COMMITTEE COMMENT: The benefit received from standby power is minor. For dedicated systems the associated costs would be low; for nondedicated systems the costs would be high. I t is not cost ef fect ive to require standby power for nondedicated systems.

(Log #76) 92A - If6 - (3-7.3): Accept SUBMITTER: Gregory F. DeLuga, MCC Powers COMMENT ON PROPOSAL NO.: 92A-]

I ECOMMENDATION: Revise 3-7.3 as follows: 3-7.3 Standby power should be considered for

dedicated smoke control systems and thei r control systems.

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SUBSTANTIATION: The reference to "detection" system has been removed, since the requirements for standby power for such systems is covered in the Protective Signaling System standards. COMMITTEE ACTION: Accept.

(Log #99) p

92A - 117 - ( 3 - 7 . 3 ) : Reject SUBMITTER: Edward J. Ward, Factory Mutual Research Corp. COMMENT ON PROPOSAL NO. : 92A-I RECOMMENDATION: Revise paragraph to read as follows:

"Stand-by power should be provided for smoke control systems and the i r associated detection and control system." SUBSTANTIATION: See substantiation under comment For 3-7.2 COMMITTEE ACTION : Reject. COMMITTEE COMMENT: See Committee Action and Committee Comment on Comment 92A-115 (Log #98) on 3-7.2.

(Log #101) 92A - 118 - (4 -1 . l (a ) ) : Accept in Principle SUBMITTER: John M. Watts, Jr. Fire Safety Ins t i tu te COMMENT ON PROPOSAL NO.: 92A-1 RECOMMENDATION: Replace the word "operational" with the word "component". SUBSTANTIATION: The term "operational test ing" is not d is t inc t from the concept of "acceptance test ing" as defined in paragraph 4-3.1. "Component test ing" is more descriptive of the intended procedure as defined in paragraph 4-2.3. COMMITTEE ACTION: Accept in Principle.

I Ed i to r ia l l y change "operational" to "component systems". COMMITTEE COMMENT: The Committee Action should sat is fy the Commenter's intent.

(Log #9) 92A - 119 - (4-2.2): Accept SUBMITTER: J. Brooks Semple, Smoke/Fire Risk Management, Inc. COMMENT ON PROPOSAL NO.: 92A-1 RECOMMENDATION: Add to the end of the sentence:

"including the following architectural features:" and delete from (d) "Architectural features such as". SUBSTANTIATION: All items in the l i s t are architectural features, not (d) alone. COMMITTEE ACTION: Accept.

(Log #77) 92A - 120 - (4-2.2): Reject SUBMITTER: Gregory F. DeLuga, MCC Powers COMMENT ON PROPOSAL NO.: 92A-I RECOMMENDATION: Revise the f i r s t part of 4-2.2 as follows:

"4-2.2 Prior to beginning the operational testing, the party responsible for testing should be provided with writ ten ver i f i ca t ion of the completeness of the building construction. Each party having responsibi l i ty for performing a phase of the construction and/or the insta l la t ion of equipment associated with smoke control should provide the portion of the wri t ten ver i f ica t ion which covers the i r areas of responsib i l i ty . Typical areas of responsibi l i ty include, but are not l imited to : " SUBSTANTIATION: This proposed revision addresses the prac t ica l i t y of the typical building project. Typical ly, the party responsible for smoke control testing wi l l not have had performance responsib i l i ty for a l l areas of construction and ins ta l la t ion which af fect the in tegr i t y of the smoke control system. Without assigning responsibi l i t ies For ver i f i ca t ion to the respective parties, the party responsible for testing would be placed in an unfair and generally unmanageable posit ion. COMMITTEE ACTION: Reject. COMMITTEE COMMENT: Requiring "writ ten ver i f i ca t ion" is unreal ist ic.

(Log #39) 92A - 121 - (4-2.4): Accept in Principle SUBMITTER: Rob Zivney, MCC Powers COMMENT ON PROPOSAL NO.: 92A-] RECOMMENDATION: Revise wording before the comma to read:

"Since smoke control systems usually involve an integration of building systems". SUBSTANTIATION: Corrects an inaccurate statement. COMMITTEE ACTION: Accept in Principle.

Revise the introductory phrase before the comma to read:

"Because smoke control systems are usually an integral part of building operating systems, . , ". COMMITTEE COMMENT: The Committee Action should sa t is fy the Commenter's intent.

(Log #23) 92A - 122 - (4-3.1): Accept in Principle SUBMITTER: Gunnar Heskestad, Factory Mutual Research Corp. COMMENT ON PROPOSAL NO.: 92A-I RECOMMENDATION: At the end of last sentence, add:

I "Wind speed, direction and outside temperature should be recorded on each test day." SUBSTANTIATION: Weather conditions may have a strong influence on system performance. COMMITTEE ACTION: Accept in Principle.

I Use the Commenter's Suggested wording but insert i t as a new 4-3.3.2 and renumber exist ing 4-3.3.2 through 4-3.3.5 as 4-3.3.3 through 4-3.3.6. COMMITTEE COMMENT: The Committee Action should sa t is fy the Commenter's intent.

(Log #]02) 92A - 123 - (4-3.3.2(New)): Accept in Principle SUBMITTER: John H. Watts, Jr. Fire Safety Ins t i t u te COMMENT ON PROPOSAL NO.: 92A-l RECOMMENDATION: Add new paragraph:

4-3.3.2 Record weather data; temperature, wind direction and veloci ty .

Renumber present paragraphs 4-3.3.2 through 4-3.3.5. SUBSTANTIATION: As stated in paragraph I-6.3, weather is an important design parameter. A smoke control system which functions properly in good weather may fa i l under more adverse conditions. Weather data is important For evaluating the test. COMMITTEE ACTION: Accept in Principle.

See Committee Action on Comment 92A-122 (Log #23) on 4 - 3 . 1 .

COMMITTEE COMMENT: The Comm@ttee Action on Log #23 should sat is fy the Commenter's intent.

(Log #78) 92A - 124 - (4-3.4.1): Accept in Principle SUBMITTER: Gregory F. DeLuga, MCC Powers COMMENT ON PROPOSAL NO.: 92A-l RECOMMENDATION: Revise 4-3.4.1 as follows:

4-3.4.1 Without any smoke control systems in operation, measure and record the pressure difference across each stairtower door while the door is closed. After recording the pressure differ.ence across the door, measure the force necessary to open each door, using a spring type scale. Establish a consistent procedure for recording data throughout the ent ire test, such that the stairtower side of the doors w i l l always be considered as the reference point, (0 PSI) and the f loor side of the doors w i l l always have the pressure difference value (posi t ive i f higher than the stairtower and negative when less than the stairtower). Since the stairtower pressurization system is intended to produce a posit ive pressure within the stairtower, a l l negative pressure values recorded on the f loor side of the doors are indicat ive of a potential a i r flow into the f loor . SUBSTANTIATION: This proposed revision establishes a uniform approach to recording data such that the stairtower w i l l always be the pressure reference point.

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~OMMITTEE ACTION: Accept in Principle. Replace 4-3.4.1 with the following: 4-3.4.1 With a l l building HVAC systems in normal

operation, measure and record the pressure difference across each stairtower d o o r . . . (continue with Commenter's wording) . . . . COMMITTEE COMMENT: The Committee Action should sat is fy the Commenter's intent.

(Log #79) 92A - 125 - (4-3.4.2): Accept SUBMITTER: Gregory F. DeLuga, MCC Powers COMMENT ON PROPOSAL NO.: 92A-I RECOMMENDATION: Revise 4-3.4.2 as follows:

4-3.4.2 Veri fy the proper activation of the stairtower pressurization system(s) in response to a l l means of activation, both automatic and manual, as specified in the contract documents. Where automatic activation is required in response to alarm signals received from the building's protective signaling system, each separate alarm signal should be in i t ia ted to ensure that proper automatic activation occurs. SUBSTANTIATION: The proposed revision incorporates the need to test the proper activation of stairtower pressurization systems in conjunction with thei r overall effectiveness at creating proper stat ic presure levels. COMMITTEE ACTION: Accept.

(Log #80) 92A - 126 - (4-3.4.3): Accept SUBMITTER: Gregory F. DeLuga, MCC Powers COMMENT ON PROPOSAL NO.: 92A-I RECOMMENDATION: Revise 4-3,4.3 as follows:

4-3.4.3 With the stairtower pressurization system activated, measure and record the pressure difference across each stairtower door with a l l doors closed. SUBSTANTIATION: The revision is proposed as a more appropriate statement part icular ly i f 4-3.4.2 is revised to cover proper stairtower pressurization system activation. COMMITTEE ACTION: Accept.

(Log 481) 92A - 127 - (4-3.4.4): Accept in Principle SUBMITTER: Gregory F. DeLuga, MCC Powers COMMENT ON PROPOSAL NO.: 92A-I RECOMMENDATION: Revise 4-3.4.4 as follows:

4-3.4.4 With the stairtower pressurization system activated, open one selected door and measure and record the d i f fe rent ia l pressure across each remaining closed stairtower door. After recording the pressure difference across each closed door, measure the force necessary to open each door, using a spring type scale. Use the same procedure as established in 4-3.4.1 to record data throughout the entire test. The local code and contract documents should be followed regarding the door to be opened for this test. SUBSTANTIATION: This revision is proposed for consistency with the previous test procedures, beginning with 4-3.4.1. COMMITTEE ACTION: Accept in Principle.

I Revise 4-3.4.4 as follows: 4-3.4.4 With the stairtower pressurization system

, activated, use a spring scale to measure, and then record, the force needed to open one selected door. With the i n i t i a l door held in the open position,

i measure and record the pressure difference across each remaining . . . (continue with Commenter's wording). . . COMMITTEE COMMENT: The Committee Action should sat is fy the Commenter's intent.

(Log #82) 92A - 128 - (4-3.4.5): Accept in Principle SUBMITTER: Gregory F. DeLuga, MCC Powers COMMENT ON PROPOSAL NO.: 92A-1 RECOMMENDATION: Revise 4-3.4.5 as follows:

I 4-3.4.5 With the stairtower pressurization system i activated, open the required additional doors, one at a

time, and measure and record the pressure difference across each remaining closed stairtower door a f ter the opening of each additional door. After recording the

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pressure difference across each closed door, measure the force necessary to open each door, using a spring type scale. Use the same procedure as established in 4-3.4.1 to record data throughout the entire test. The local code and contract documents should be followed regarding the number and location of a l l doors which need to be opened For this test. I t is suggested that a minimum of three doors be used, with the ground Floor door as the f i r s t door to be open. SUBSTANTIATION: This revision is proposed for consistency with the previous test procedures, beginning with 4-3.4.1, and to include the ground f loor door with respect to the admonition expressed in paragraph 2-3.5.1(c). COMMITTEE ACTION: Accept in Principle.

Revise ¢-3.4.5 as suggested by the Commenter but in the Commenter's next to the last sentence insert the word "requirements" af ter the words "contract documents" and delete the Commenter's last proposed sentence. COMMITTEE COMMENT: The Committee Action Should sat isfy the Commenter's intent.

(Log #83) 92A - 129 - (4-3.4.6): Accept in Principle SUBMITTER: Gregory F. DeLuga, MCC Powers COMMENT ON PROPOSAL NO.: 92A-1 I RECOMMENDATION: Revise 4-3.4.6 as follows:

4-3.4.6 With the stairtower system activated, and i a l l required doors open as covered by 4-3.4.5,

determine and record the direction of a i r flow through I each of the open doors. This can be done by a small

amount of smoke at the open doorway or by temporarily securing a 6 Ft long str ip of tissue to the top of the

i door Frame. I f a i r velocity measurements are required, the measurement should be made at the door Frame with the door f u l l y open. SUBSTANTIATION: This revision is proposed as an improvement of the existing text. COMMITTEE ACTION: Accept in Principle.

I Revise 4-3.4.6 as suggested by the Commenter, but change the Commenter's last proposed sentence to read:

I I f velocity measurements are required, a door opening traverse needs to be performed with the door f u l l y open. COMMITTEE COMMENT: The ConTnittee Action should sat isfy the Commenter's intent.

(Log #40) 92A - 130 - (4-3.5.2): Reject SUBMITTER: Rob Zivney, MCC Powers COMMENT ON PROPOSAL NO.: 92A-I RECOMMENDATION: Delete and renumber remaining paragraphs. SUBSTANTIATION: This is a very expensive requirement with l i t t l e value. Observing the correct operation of fans, dampers, and related equipment as stated in the f i r s t part of paragraph 4-3.5.3 provides the basic assurance that the system w i l l work properly for most conventional applications. The question must be asked "What w i l l be done i f expected pressure readings are not obtained?" Such pressure readings should only be suggested for unusual applications, and then on a spot check basis. COMMITTEE ACTION: Reject. COMMITTEE COMMENT: I t is essential that this test be done in order to have confidence in the system.

(Log #84) 92A - 131 - (4-3.5.2): Accept in Principle SUBMITTER: Gregory F. DeLuga, MCC Powers COMMENT ON PROPOSAL NO.: 92A-I RECOMMENDATION: Revise 4-3.5.2 as follows:

4-3.5.2 Measure and record the d i f fe ren t ia l pressure across a l l smoke control zones which divide a building f loor . The measurements should be made while the HVAC systems serving the f l oo r ' s smoke zones are operating in their normal (nonsmoke control) mode. The measurements should be made while a l l smoke barr ier doors which separate the f loor zones are closed. One measurement should be made across each smoke barr ier door or set of doors, and the data should c lear ly indicate the higher and lower pressure sides of the doors.

SUBSTANTIATION: The proposed revision is suggested as a c la r i f i ca t ion and improvement of the exist ing tex t . COMMITTEE ACTION: Accept in Principle.

Revise 4-3.5.2 as the Commenter suggests, but in the Commenter's f i r s t sentence, change "d i f fe ren t ia l pressure" to "pressure dif ference". COMMITTEE COMMENT: The Committee Action should sat is fy the Commenter's intent.

(Log #85) 92A - 132 - (4-3.5.3): Accept SUBMITTER: Gregory F. DeLuga, MCC Powers COMMENT ON PROPOSAL NO.: 92A-I RECOMMENDATION: Revise 4-3.5.3 to cover only the correct act ivat ion of zoned smoke control systems, and add additional paragraphs to cover pressure measurements across doors as follows:

4-3.5.3 Veri fy the proper act ivat ion of each zoned smoke control system in response to a l l means of act ivat ion, both automatic and manual, as specified in the contract documents. Where automatic act ivat ion is required in response to alarm signals received From the building's protective signaling system, each separate alarm signal should be in i t ia ted to ensure that proper automatic act ivat ion of the correct zoned smoke control system occurs. Ver i fy and record the proper operation of al l fans, dampers, and related equipment as outlined by the schedule(s) referenced in 3-4.5.4 for each separate zoned smoke control system. SUBSTANTIATION: The proposed revision covers the testing of the proper act ivat ion of zoned smoke control systems in a separate paragraph pr ior to making pressure measurements. COMMITTEE ACTION: Accept.

(Log #86) 92A - 133 - (4-3.5.3): Accept SUBMITTER: Gregory F. OeLuga, MCC Powers COMMENT ON PROPOSAL NO.: 92A-1 RECOMMENDATION: Incorporate the Pressure measurement portion of existing paragraph 4-3.5.3 into new paragraph 4-3.5.4 as follows:

4-3.5.4 Activate the zoned smoke control system(s) which are appropriate for each separate smoke control zone. Measure and record the pressure difference across al l smoke barr ier doors which separate the smoke zone from adjacent zones. The measurements should be made while a l l smoke barr ier doors which separate the smoke zone from the other zones are Fully closed. One measurement should be made across each smoke barr ier door or set of doors, and the data should clearly indicate the higher and lower pressure sides of the doors. Doors which have a tendency to open s l i gh t l y due to the pressure difference should have one pressure measurement made while held closed and another made while not held closed. SUBSTANTIATION: The proposed revision is suggested as a c la r i f i ca t ion and improvement of the existing tex t . COMMITTEE ACTION: Accept.

(Log #87) 92A - 134 - (4-3.5.4): Accept SUBMITTER: Gregory F. DeLuga, MCC Powers COMMENT ON PROPOSAL NO.: 92A-1 RECOMMENDATION: Renumber ex i s t i ng paragraph 4-3.5.4 to 4-3.5.5, and revise as fo l l ows :

4-3.5.5 Continue to act ivate each separate zoned smoke control system and make pressure difference measurements as described in the Preceeding paragraph. Ensure that af ter testing a smoke zone's smoke control system, i t is properly deactivated and the NVAC systems involved are returned to the i r normal operating mode pr ior to activating another zone's smoke control system. Also ensure that a l l controls necessary to prevent excessive pressure differences are functional to prevent deunage to ducts as related building equipment. SUBSTANTIATION: The revision is proposed as an improvement on the exist ing tex t . ~OMMITTEE ACTION: Accept.

(Log #1331 92A - 135 - (4-3.6.2): Reject SUBMITTER: C.V. Lovett, Easton, CT COMMENT ON PROPOSAL NO.: 92A-1 RECOMMENDATION: Revise as follows:

(c)* Delete "real Fire tests". SUBSTANTIATION: I would hope the NFPA is not endorsing the use of "real f i res" to test a smoke management system. Just because a one(1) test was conducted in Germany is this a reason/cause to endorse th is method. Who takes the l i a b i l i t y in th is type of test i f something goes wrong? COMMITTEE ACTION: Reject. ~OMMITTEE COMMENT: The exist ing wording, as Found in the TCR, represents a factual statement with respect to methods used in the past. The appendix item Further explains the method. I t should be retained.

(Log #130) 92A - 136 - (4-3.6.2): Reject SUBMITTER: C.V. Lovett, Easton, CT COMMENT ON PROPOSAL NO.: 92A-I RECOMMENDATION: Add additional warnings and precautions ( i .e . building should not be occupied, f i r e authori t ies are to be not i f ied of the use of smoke being used and not to respond unless f i r e - how do you distinguish test smoke From area/f i re smoke? etc.) SUBSTANTIATION: Some statements must be added as to the precautions, hazards to be encounted and what should be done to eliminate problems, l i a b i l i t y , damage, etc. This should be unacceptable to give examples of hazardous test methods without giving any precautionary guidance. COMMITTEE ACTION: Reject. COMMITTEE COMMENT: The existing wording, as found in the TCR, gives "examples" o£ tests that have been used. The existing wording does not recommend that this specif ic test be used.

(Log #101 92A - 137 - (4-3.9): Reject SUBMITTER: J. Brooks Semple, Smoke/Fire Risk Management, Inc. COMMENT ON PROPOSAL NO.: 92A-I RECOMMENDATION: Add to the end of the paragraph:

"Retest upon fu l l occupancy. See 2-6". SUBSTANTIATION: Such retesting is necessary for proper system balance. The explanation is in 2-6. COMMITTEE ACTION: Reject. COMMITTEE COMMENT: The Commenter's proposed provision for system retesting as-a-whole upon f u l l occupancy is unworkable, expensive and unreal ist ic to implement.

(Log #11) 92A - 138 - (4-4.3): Accept SUBMITTER: J. Brooks Semple, Smoke/Fire Risk Management, Inc. COMMENT ON PROPOSAL NO.: 92A-1

I RECOMMENDATION: On l ine 5 delete "safet ies" add " l im i t controls". SUBSTANTIATION: The more specif ic term also eliminates slang. COMMITTEE A~TION: Accept.

(Log #1001 92A - 139 - (Chapter 5(New)): Accept SUBMITTER: John M. Watts, J r . , Fire Safety Ins t i t u te COMMENT ON PROPOSAL NO.: 92A-l RECOMMENDATION: Add new chapter:

Chapter 5 Referenced Publications SUBSTANTIATION: Document contains numerous references to inadequately ident i f ied documents. These documents should be l is ted in accordance with paragraph 2-6.1 of NFPA 1M-1986, Manual of Style. Hopefully th is w i l l include a c i ta t ion For the source of the numbers in Table 2- I . COMMITTEE ACTION: Accept.

113

(Log #140) 92A - 140 - (A-2-2.1(New)): Accept SVBMITTER: John H. Klote, National Bureau of Standards COMMENT ON PROPOSAL NO.: 92A-I RECOMMENDATION: Add new text as follows:

A-2-2.1 A smoke control system should be designed to maintain the minimum design pressure differences under l i ke l y conditions of stack effect or wind. The minimum design pressure differences of Table 2-I for nonsprinklered spaces are values that w i l l not be overcome by buoyancy forces of hot gases. The method used to obtain the values of Table 2-I for nonsprinklered spaces is described below. The pressure difference due to buoyancy of hot gases is calculated by the following equation:

AP = 7.64 [ 1 I ] To TF h

where: AP = pressure difference due to buoyancy of hot

gases in inches of water gage To = absolute temperature of surroundings in

degrees R TF = absolute temperature of hot gases in

degrees R h = distance above neutral plane in Feet The neutral plane is a horizontal plane between the

f i r e Space and a surrounding space at which the pressure difference between the f i r e space and the surrounding space is zero. For Table 2-I, h was conservatively selected at 2/3 of the f loor to cei l ing height, the temperature of the surroundings was selected at 70°F, the temperature of the hot gases was selected at 1700°F, and a safety factor of 0.03 inches water gage was used.

EXAMPLE: Calculate the minimum design pressure difference For a ceil ing height of 12 f t .

To = 70 + 460 = 530 OR T~ = 1700 + 460 = 2160 OR h = (12) 2/3 = 8 f t From the above equation AP = .087 inches water

gage. Adding the safety factor and rounding o f f , the minimum design pressure difference is 0.12 inches water gage. SUBSTANTIATION: An appendix section te l l ing how Table 2-I was calculated would be of use to readers. Readers can calculate values for other cei l ing heights and other hot gas temperatures. COMMITTEE ACTION: Accept.

(Log #I) 92A - I~I - (Appendix A, A-3-4.3.4): Reject SVBMITTER: Thomas C. Campbell, TIMA COMMENT ON PROPOSAL NO.: 92A-I RECOMMENDATION: In the item "OPEN-AUTO-CLOSE" at the bottom of the f i r s t column add a note as follows:

"Note: Where combination fire/smoke dampers are used, controls shall not be capable of reopening such dampers which have fused unti l temperatures in the area of the dampers have dropped below the Fusing temperature of fusable l ink." SVBSTANTIATION: To allow any person to reopen f i r e dampers which have fused, while the temperature of the a i r around or in the duct is s t i l l above the Fusing temperature of the l ink, w i l l jeopardize the effectiveness of the Fire barrier which is penetrated. COMMITTEE ACTION: Reject. COMMITTEE COMMEN!: The subject has already been adequately addressed by the Committee Action on Comment 92A-92 (Log #I06) on 3-4.3.4.

(Log #12) 92A - 142 - (A-3-4.3.¢): Accept SUBMITTER: J. Brooks Semple, Smoke/Fire Risk Management, Inc. COMMENT ON PROPOSAL NO.: g2A-I RECOMMENDATION: On f i r s t paragraph, second column, top of page 14, l ine 3, delete "as a single piece of equipment" add: "co l lect ive ly" . SUBSTANTIATION: Shorter and clearer; same basic meaning. COMMITTEE ACTION: Accept.

(Log #13) 92A - 143 - (A-3-4.3.4): Accept SVBMITTER: J. Brooks Semple, Smoke/Fire Risk Management, Inc. COMMENT ON PROPOSAL NO.: 92A-I 114

RECOMMENDATION: On f i f t h paragraph, second column, top of page 14, lines 2 and 4 delete: "source".

add: "control point". Also seventh paragraph, l ine 3 delete: "sources". add: "control points". AIso eighth paragraph, l ine 4 delete: "source" add: "point".

SUBSTANTIATION: The term "source" is more often associated with e lectr ical power that with control. The substitution is specif ic. COMMITTEE ACTION: Accept.

(Log #14) 92A 144 - (A-3-4.3.4): Accept SUBMITTER: J. Brooks Semple, Smoke/Fire Risk Management, Inc. COMMENT ON PROPOSAL NO.: 92A-I RECOMMENDATION: Paragraph 10, second column, page 14, at the end of l ine 5, move up existing phrase at the end of the sentence:

", as well as the building areas served by the smoke control systems,"

On l ine 7, add a period af ter "panel". SUBSTANTIATION: The present sentence is what we native Pennsylvanians call "Dutch" as in "Throw the cow over the Fence some hay." or "Throw your mother from the train a kiss."

We believe the meaning is more readily understood as restated. COMMITTEE ACTION: Accept.

(Log #15) 92A - 145 - (A-4-3.6.2(a)): Accept SUBMITTER: J. Brooks Semple, Smoke/Sire Risk Management, Inc. COMMENT ON PROPOSAL NO.: 92A-I RECOMMENDATION: First f u l l paragraph, top of page 15, l ine 5:

delete: "However,". SUBSTANTIATION: The word is misused because the balance of the sentence is a restatement of the previous one, not an exception. COMMITTEE ACTION: Accept.

(Log #25) 92A - 146 - (A-4-3.6.2(a)): Reject SUBMITTER: Rob Zivney, MCC Powers COMMENT ON PROPOSAL NO.: 92A 1 RECOMMENDATION: Relocate paragraph 4, beginning with the second sentence to I-5.1 at the end of the third paragraph (which begins with: The di lut ion of . . . ) . Precede the relocated text with the sentence: "Such di lut ion systems are sometimes called purging systems." SUBSTANTIATION: This subject matter is too important to be in the appendix. Also the concept is not limited to Chemical Smoke Tests. COMMITTEE ACTION: Reject. COMMITTEE COMMENT: The Commenter's proposed relocation and addition of language is unwarranted. The intent behind the existing language is that i t serve as explanation and thus should remain in the appendix.

(Log #131) 92A - 147 - (A-4-3.6.2(c)): Accept in Principle ~UBMITTER: C.V. Lovett, Easton, CT COMMENT ON PROPOSAL NO.: 92A-I RECOMMENDATION: Delete the last part of the last paragraph "or as part of an acceptable test as was done at Hamburg." SUBSTANTIATION: Is this NFPA committee going to take the l i a b i l i t y for a Full scale f i r e test in a mult imil l ion dol lar building ready to be used/occupied? Just because of only one documented test in the world (as described by this Recommended Practice) is this to be expected on a l l new system concepts? Testing in research f a c i l i t i e s is fine under these controlled situations. COMMITTEE ACTION: Accept in Principle.

In the last ( f i f t h ) paragraph of A-4-3.6.2(c), delete wording from the last sentence so as to end that sentence with the words: ". . . should be Fire tested." COMMITTEE COMMENT: The Committee Action should sat is fy the Commenter's intent.

The following draft is presented as an aid to the reviewer. I t incorporates the Committee Actions on the 147 Public Comments received and processed by the Technical Committee on Smoke Managment Systems.

NFPA 92A

Recommended Practice for

Smoke Control Systems

1988 Edition

NOTICE: An asterisk (~) following the number or l e t t e r designating a paragraph indicates explanatory material on that paragraph in Appendix A.

Chapter I General Information

1-1 Introduction. All f i res produce smoke which, i f not controlled, wi l l spread throughout the building or portions of the building thereby endangering l i f e and damaging property.

A smoke control system should be designed to inh ib i t the flow of smoke into means of egress, ex i t passageways, or other similar areas of a building. Limiting f i r e size by provision of automatic sprinklers or other means of automatic suppression w i l l generally be necessary for ef fect ive and economical control of smoke in most occupancies. Other techniques may be appropriate for specialized occupancies or exist ing f a c i l i t i e s . When smoke control systems are provided, they should be activated during the early stages of a f i r e emergency to maintain a tenable environment in the areas to be protected. The smoke control system should be functional during the period of evacuation of the areas protected by the system. Such systems are intended to control the migration of smoke to maintain tenable conditions in protected areas, but i t should not be expected that such areas would be completely free of smoke. Smoke control systems should be engineered for the specific occupancy and building design. Addit ional ly, the smoke control system design should be coordinated with other l i f e safety systems so that they complement, rather than counteract, each other•

I-2 Scope. This recommended practice applies to the design, insta l la t ion, testing, operation, and maintenance of new and re t ro f i t t ed mechanical a i r conditioning and vent i la t ion systems for the control of smoke. This recommended practice also applies to systems dedicated solely to the control of smoke. The problem of maintaining tenable conditions within large zones of f i r e or igin, such as at r ia and shopping malls, is not addressed by this document. See NFPA 204M, Guide for Smoke and Heat Venting, for smoke and heat venting.

I-3 Purpose. The purpose of this recommended practice is to provide guidance in implementing systems to accomplish one or more of the following:

(a) Maintain a tenable environment in the means of egress during the time required for evacuation.

(b) Control and reduce the migration of smoke from the f i r e area.

(c) Provide conditions outside the f i r e zone which w i l l assist emergency response personnel to conduct search and rescue operations and to locate and control the f i r e .

(d) Contribute to the protection of l i f e and reduction of property loss.

I-4 Definit ions. The following terms For the purposes o f this recommended practice shall have the meanings given in this chapter.

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Fire Fighter's Smoke Control Station. Fire f igh te r ' s smoke control stat ion (FSCS) includes monitoring and overriding capabi l i ty over smoke control systems and equipment provided at designated location(s) within the building for the use of the f i r e department. Other f i r e f ighters ' systems (such as voice alarm, public address, f i r e department communication, and elevator status and controls) are not covered in this document.

Pressurized Stairtowers. A type of smoke control system in which s ta i r shafts are mechanically pressurized with outdoor a i r to keep smoke from contaminating them during a f i r e incident.

Smoke. The airborne solid and l iquid particulates and gases evolved when a material undergoes pyrolysis or combustion, together with the quantity of a i r that is entrained or otherwise mixed into the mass.

Smoke Barrier. A membrane, ei ther vert ical or horizontal, such as a wall, f loor or cei l ing assembly, that is designed and constructed to res t r i c t the movement of smoke. A smoke barr ier may or may not have a f i r e resistance rat ing. Smoke barriers may have openings protected by closing devices or adequate a i r flows. •

Smoke Control Mode. A predefined operational configuration of a system or device for the purpose of smoke control.

Smoke Control System. An engineered system that uses mechanical fans to produce airf lows and pressure differences across smoke barriers to l im i t and direct smoke movement.

Smoke Control Zone. A space within a building enclosed by smoke barriers, including the top and bottom, which is part of a zoned smoke control system.

Smoke Damper. A device to resist the passage of a i r or smoke which meets the requirements of UL 555S, Standard for Leakage Rated Dampers for Use in Smoke Control Systems. A combination f i r e and smoke damper should meet the requirements of UL 555, Standard For Fire Dampers and Ceiling Dampers, and UL 555S.

Smoke Exhaust System. A mechanical or gravi ty system intended to move smoke from the smoke zone to the exter ior of the building, including smoke removal, purging, and venting systems as well as the function of exhaust fans u t i l i zed to reduce the pressure in a smoke zone. Maintenance of a tenable environment in the smoke zone is not within the capabi l i ty of these systems.

Smoke Zone. The smoke control zone in which the f i r e is located.

Stack Effect. The vert ical a i r flow within buildings caused by temperature differences between the building in ter io r and exter ior .

Tenable Environment. An environment in which the quantity and location of smoke is l imited or otherwise restr icted so as to allow readi ly for evacuation through the space.

Zoned Smoke Control. A smoke control system which includes smoke exhaust For the smoke zone and pressurization for a l l contiguous smoke control zones. The remaining smoke control zones in the building also may be pressurized•

1-5 Principles of Smoke Control.

I-5.1 Basic Principles. Frequently smoke flow follows the overall a i r movement within a building. Although a Fire n~y be confined within a f i r e - res i s t i ve compartment, smoke can readi ly spread to adjacent areas through openings, such as construction cracks, pipe penetrations, ducts and open doors. The principal factors that cause smoke to spread to areas outside a compartment are:

(a) stack ef fect .

(b) temperature ef fect of f i r e .

(c) weather conditions, par t icu lar ly wind and temperature.

(d) mechanical air-handling systems.

The factors above cause pressure differences across part i t ions, walls, and f loors which can result in the spread of smoke. The movement of smoke can be controlled by al ter ing these pressure differences. Building components and equipment such as walls, f loors, doors, dampers, and smokeproof stairtowers can al l be u t i l i zed along with the heating, vent i la t ing, and a i r conditioning (HVAC) systems to aid in the control of the movement of smoke. Proper overall building design and t i gh t construction are essential to smoke control.

The d i lu t ion of smoke in the f i re area of a compartmented building is not a means of achieving smoke control. Smoke control cannot be achieved by simply supplying a i r to and exhausting a i r from the compartment.

Smoke control can be stated in two basic principles as follows:

(a) Air pressure differences of suf f ic ient magnitude acting across barriers wi l l control smoke movement.

(b) Airf low by i t s e l f w i l l control smoke movement i f the average a i r ve loc i ty is of suf f ic ient magnitude.

I -5.2 Pressurization. The primary means of control l ing smoke movement is by creating a i r pressure differences across part i t ions, f loors and other building components. The basic concept of building pressurization is to establish a higher pressure in adjacent spaces than in the smoke zone. In th is way a i r moves into the smoke zone from adjacent areas and smoke is inhibited From dispersing throughout the building.

l -5.3 Airflow. Airf low can be used to stop movement through a space. This principle is most commonly used to control smoke movement through open doorways. The flow of a i r through the opening into the smoke zone must be of suf f ic ient veloci ty to prevent smoke from leaving that zone through such openings. Since the quantit ies of a i r required are large, air f low is not the most practical method of control l ing smoke movement.

I-6 Design Parameters.

l - 6 . l General. Design c r i t e r i a contained in the governing codes or the standards referenced by them should be used. However, they should be scrutinized to determine whether or not they wi l l result in an ef fect ive system. I f necessary, the designer should seek equivalencies or modifications to the local codes. This would include an understanding with the authori ty having ju r isd ic t ion of the expected performance of the system and the acceptance test procedures. Detailed engineering design information is contained in the ASHRAE publication, "Design of Smoke Control Systems for Buildings".

l -6.2 Leakage Area Parameters. Design c r i t e r i a and acceptance testing of smoke control systems should be based upon the following parameters with reference to the smoke zone and adjacent zones:

(a) Small openings in smoke barriers such as construction jo in ts , cracks, closed door gaps, and similar clearances should be addressed in terms of maintaining an adequate pressure difference across the smoke barr ier, with the posit ive pressure outside of the smoke zone.

(b) Large openings in smoke barriers such as doors intended to be open, and other sizable openings should be addressed in terms of maintaining an adequate a i r veloci ty across the smoke barr ier, with the a i r flow direct ion into the smoke zone.

1-6.3 Weather Data. The temperature differences between the exter ior and in ter ior of the building causes stack effect and determines i ts direct ion and

magnitude. The ef fect of temperature and wind ve loc i ty wi l l vary with building height, configuration, leakage, and openings in wall and f loor construction.

I-6.5 Pressure Differences. The maximum and minimum allowable pressure differences across the boundaries of smoke control zones should be considered. The maximum should not result in door-opening forces that exceed the requirements of NFPA IOl~, Life Safety Code~, or local codes and regulations. The minimum should be such that there wi l l be no s igni f icant smoke leakage during building evacuation. For the system to be effect ive, the pressure needs to be enough that i t is not overcome by the forces of wind, stack ef fect , or buoyancy of hot smoke.

I-6.6 Airflow. Airf low can be used to l imi t smoke migration when doors in smoke control barriers are open. The design veloci ty through an open door should be suf f ic ient to prevent smoke backflow during building evacuation. I t should take into consideration the same variables as used in the selection of design pressure differences.

I-6.7 Number of Doors Open. The number of doors that may be open simultaneously should be considered. This number wi l l depend largely on the building occupancy and the type of smoke control system. In some systems, doors wi l l most l i ke l y be open for only short periods of time and the smoke leakage wi l l be negligible.

I-7 Fire Suppression Systems. Automatic sprinkler and other suppression systems are an integral part of many f i r e protection designs and the r e l i a b i l i t y and eff iciency of such systems in control l ing building f i res is well documented. I t is important to recognize that the functions of suppression and smoke control systems are both important. Automatic suppression systems can extinquish a Fire early in i t s growth thereby eliminating additional smoke generation. On the other hand, well designed smoke control systems can maintain a tenable environment along c r i t i ca l egress routes during the time i t takes the Fire suppression system or f i r e service personnel to achieve extinguishment.

In addition to the fact that the systems perform di f ferent functions, i t is important to consider the interaction between the smoke control and Fire suppression systems, for example, in the case of a f u l l y sprinklered building, pressure differences and airflows needed to control smoke movement may be less than in an unsprinklered building due to the l ikel ihood that the maximum f i re size wi l l be s ign i f i can t ly smaller than in an unsprinklered building.

A smoke control system can adversely af fect the performance of a gaseous agent (such as Halon, C02 of N2) suppression system when the systems are located in a common Space. In the event that both systems are activated concurrently, the smoke control system may di lute the gaseous agent in the space. Since gaseous suppression systems commonly provide only one application of the agent, the potential arises for renewed growth of the f i r e . Gaseous suppression systems and smoke control systems cannot perform thei r intended functions simultaneously when they are located within the same space.

l - 8 Testing. See 4- I .

I -9 Maintenance. See 4-4.

Chapter 2 Smoke Control Systems and Appl icab i l i ty

2-I Introduction.

2-I.1 Purpose. This Chapter discusses various types of smoke control systems which are currently available and reviews the advantages and disadvantages of each.

Determination of system objectives and performance c r i te r ia should be made pr ior to design or construction.

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2-I .2 Dedicated and Nondedicated Systems.

2-I .2.1 Dedicated Systems.

(a) Dedicated smoke control systems are intended for the purpose of smoke control only. They are separate systems of a i r moving and d is t r ibut ion equipment which do not function under normal building operating conditions. Upon act ivat ion, these systems operate speci f ica l ly to perform the smoke control function.

(b) Dedicated systems have the following advantages:

I . Modification of the controls during system maintenance is less l i k e l y to occur.

2. Operation and control is generally simpler.

3. They are less l i k e l y to be affected by the modification of other building systems,

(c) They have the following disadvantages:

I . Dedicated systems may be more costly.

2. Component fa i lures may go uncorrected since they do not affect normal building operation.

3. Systems frequently require more building space.

2-1.2.2 Nondedicated Systems.

(a) Nondedicated systems are those which share components with some other system(s) such as the building HVAC system. Activat ion causes the system to change i ts mode of operation to achieve the smoke control objectives.

(b) Nondedicated systems have the following advantages:

I . Component fa i lures of equipment which is required for normal building operation are less l i ke l y to remain uncorrected.

2. Equipment costs may be lower.

3. Additional space For smoke control equipment may not be necessary.

(c) They have the following disadvantages:

I . System control may become elaborate.

2. Inadvertent modification of controls affecting smoke control func t iona l i ty is more l i ke l y to occur.

3. Other system modifications may interfere with smoke control system operation.

2-1.3 Basic System Types. Systems for control l ing smoke movement in a building can generally be divided into two separate types: shaft protection and f loor protection. Shaft protection can be further divided into stairtower pressurization systems and elevator hoistway systems. Floor protection encompasses several variations of zoned smoke control. Use of a part icular system or combination of systems is dependent on building and f i r e code requirements, as well as specif ic occupancy and life safety requirements, of the si tuat ion being considered.

2-1.4 Tenable Environment. A nonsmoke zone of a zoned smoke control system may be used as an area intended to protect occupants for the period of time needed For evacuation. The concept of area of tenable environment in which building occupants could wait out large f i res has not achieved wide acceptance and design c r i te r ia have yet to be developed.

2-1.5 System In teg r i t y . Smoke control systems should be designed, instal led, and maintained such that the system wi l l remain ef fect ive during evacuation of the

protected areas. Other considerations may dictate that a system should remain ef fect ive for longer periods of time. Items which should be considered are:

Ca) Re l iab i l i t y of power source(s).

(b) Arrangement of power d is t r ibu t ion .

(c) Method and protection of controls and system monitoring.

(d) Equipment materials and construction.

(e) Building occupancy.

2-2 Pressure Differences.

2-2.1" The following table of suggested minimum design pressure differences was developed for gas temperature of 1700°F next to the smoke barr ier .

Table 2-1 Suggested Minimum Design Pressure Difference Across Smoke Barriers (1)

Cinches Water Gage)

DESIGN BLDG. CEILING PRESSURE TYPE (2> HEIGHT DIFFERENCE (3}

AS ANY .05 NS 9 f t . I0 NS 15 f t .14 NS 21 f t .18

NOTE I : For design purposes, a smoke control system should maintain these minimum pressure differences under l i ke l y conditions of stack ef fect or wind.

NOTE 2: AS - Sprinklered, NS - Nonsprinklered.

NOTE 3: The pressure difference measured between the smoke zone and adjacent spaces, while the affected areas are in the smoke control mode.

I f i t is desired to calculate pressure differences For gas temperatures other than 1700°F, the method described in Appendix A may be used. Pressure differences produced by smoke control systems tend to f luctuate due to the wind, fan pulsations, doors opening, doors closing, and other factors. Short term deviations From the suggested minimum design pressure difference may not have a serious ef fect on the protection provided by a smoke control system. There is no clear cut value of allowable value of this deviation. I t depends on tightness of doors, tightness of construction, t ox i c i t y of smoke, a i r Flow rates, and on the volumes of spaces. Intermit tent deviations up to 50% of the suggested minimum design pressure difference are considered tolerable in most cases.

2-2.2 Similar ly, the pressure difference across doors should not exceed the values given in Table 2-2 so that the doors can be operated while the pressurization system is operating. These values are based on the 30 Ib f (133 N) maximum force to begin opening the door stipulated in NFPA 101, Life Safety Code.

Table 2-2 Maximum Pressure Differences Across Doors ( I } ' (z). (3). (4). (s)

Cinches Water Gage)

Door Closer Door Width (Inches) Force (6) ( Ib f ) 32 36 40 44 48

6 0 . 4 5 0 . 4 0 0 . 3 7 0 . 3 4 0 .31 8 0 .41 0 . 3 7 0 . 3 4 0 .31 0 . 2 8

10 0 . 3 7 0 . 3 4 0 . 3 0 0 . 2 8 0 . 2 6 12 0 . 3 4 0 . 3 0 0 . 2 7 0 . 2 5 0 . 2 3 14 0 . 3 0 0 . 2 7 0 . 2 4 0 . 2 2 0 .21

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Notes:

I. Total door opening Force is 30 IbF. 2. Door height is 7 Ft. 3. The distance from the doorknob to the knob side

of the door is 3 in. 4. For other door-opening Forces, other door sizes,

or hardware other than a knob, e.g., panic hardware, use the calculation procedure provided in the ASHRAE publication "Design of Smoke Control Systems For Buildings".

5. Door widths apply only i f door is hinged at one end, otherwise use the calculation procedure provided in the ASHRAE publication "Design of Smoke Control Systems for Buildings".

6. Many door closers require less force in the in i t ia l portions of the opening cycle than that required to bring the door to the f u l l open position. The combined impact of the door closer and the imposed pressure combine only unti l the door is opened enough to allow a i r to pass f reely through the opening. The Force imposed by a closing device to close the door is often d i f ferent from that imposed upon opening.

2-3 Stairtower Pressurization Systems.

2-3.1 General. The goal of pressurized stairtowers is to provide a tenable environment within the stairtower in the event of a building f i r e . A secondary objective is to provide a staging area for f i r e f ighters. On the f i r e Floor, a pressurized stairtower needs to maintain a pressure difference across a closed stairtower door so that smoke i n f i l t r a t i o n is limited.

2-3.2 Noncompensated and Compensated Systems.

(a) Noncompensated. Supply a i r is injected into the stairtower by actuating a single speed fan, thus providing one pressure difference with a l l doors closed, another difference with one door open, and so on.

(b) Compensated. Compensated systems adjust to va r i ous combinat ions o f doors open and c losed, wh i l e maintaining positive pressure differences across such openings. Systems compensate for changing conditions by either modulating supply airf lows or by rel ieving excess pressure from the stairtower.

The response time of the control system should be closely evaluated to assure that pressures do not Fall below the short term values given in Table 2-I. The location of the exhaust in let(s) from the stairtower re lat ive to the supply outlet(s) into the stairtower should be such that short c ircui t ing w i l l not occur.

(1) Modulating Supply Airflow. In this system the capacity of the supply Fan is sized to provide at least the minimum a i r veloci ty when the design number of doors are open. Figure Z-3.2(b)(1) i l l us t ra tes such a System. The Flow rate of a i r into the stairtower is varied by modulating bypass dampers, which are controlled by one or more stat ic pressure sensors that sense the pressure difference between the stairtower and the building. When a l l the stairtower doors are closed, the pressure difference increases and the bypass damper opens to increase the bypass a i r and decrease the flow of supply a i r to the stairtower. In this manner, excessive pressure differences between the stairtower and the building are prevented. The same effect can be achieved by the use of r e l i e f dampers on the supply duct when the fan is located outside the building. Supply a i r f low modulation may also be accomplished by varying fan speed, in le t vanes, variable pitch fan blades, or number of fans operating. Response times of the controls with any system should be considered.

" ° ° ' - W a , Lgvel i E x t e r i o r

_

~ l B y p a s s | ~ around Fan ~ O u t s i d e Air Intake

Fan

Figure 2 3.2(b)(1) Stairtower Pressurlzatlon with Bypass Around Supply Fan.

Notes: I. Fan bypass controlled by one or more stat ic

pressure sensors located between the stairtower and the building in ter ior .

2. A ground level supply fan is shown, however Fan(s) may be located at any level.

(2) Overpressure Relief. Compensated system operation can also be accomplished by overpressure re l i e f . In this instance, pressure buildup in the stairtower as doors close is relieved d i rect ly From the stairtower to the outside. The amount of a i r relieved varies with the number of doors open, thus attempting to achieve an essentially constant pressure in the stairtower. Exterior r e l i e f openings can be subject to adverse affects from the wind so windbreaks or windshields are recommended.

In existing buildings, overpressure r e l i e f may be discharged into the building. The effects of this on the integr i ty of the stairtowers and the interaction with other building HVAC systems should be closely studied before proposing this method. Systems using this principal should have combination Fire/smoke dampers in the s t a i r t o w e r wa l l p e n e t r a t i o n s .

Overpressure r e l i e f may be accompllshed by one of Four methods:

(a) Barometr ic dampers w i t h ad jus tab le counterweights can be used to a l l o w the damper to open when the maximum i n t e r i o r pressure is reached. This represents the s imp les t method o f overpressure r e l i e f s ince there is no phys ica l i n t e r c o n n e c t i o n between the dampers and the Fan. They a l so are the l eas t c o s t l y . The l o c a t i o n o f the dampers needs to be c a r e f u l l y chosen s ince dampers loca ted too c lose to the supply openings can operate too q u i c k l y and not a l l ow the system to meet the pressure requirements throughout the stair tower. The dampers can be subject to chattering during operation. Figure 2-3.2(b)(2) i l lus t ra tes overpressure r e l i e f using barometric dampers.

Roof Level ~ - ~ e n t to Outside

[ " ~ - I I Exterior I / 111 W a l l

- - ~ / ~ ~ Outside

Figure 2-3.2(b)(2) Stairtower Pressurization with Vent to the Outside.

118 NOTE: Supply fan may be loca ted at any l e v e l .

(b) Motor-operated dampers with pneumatic or e lect r ic motor operators may also be used. These dampers are to be controlled by d i f fe ren t ia l pressure controls located in the s ta i r tower. This method provides more positive control over the stairtower pressures than barometric dampers. I t requires more control than the barometric dampers and hence is more complicated and costly.

(c) An alternate method of venting a stairtower is through an automatically opening stairtower door to the outside at ground level. Under normal conditions this door would be closed and in most cases locked for security reasons. Provisions need to be made so that this lock does not conf l ic t with the automatic operation of the system.

Possible adverse wind effects are also a concern with a system that uses an open outside door as a vent. Occasionally, high local wind veloci t ies develop near the exterior stairtower door. Such local winds are d i f f i c u l t to estimate in the v i c i n i t y of new buildings without expensive modeling. Adjacent objects can act as windbreaks (or windshields).

(d) An exhaust Fan may be used to prevent excessive pressure when a l l stairtower doors are closed. The Fan should be controlled by a d i f fe rent ia l pressure sensor so that i t w i l l not operate when the pressure difference between the stairtower and the building f a l l s below a specified level. This should prevent the Fan From pulling smoke into the stairtower when a number of open doors have reduced stairtower pressurization. Such an exhaust Fan should be speci f ica l ly sized so that the pressurization system ~ i l l perform within design l imi ts. To achieve the desired performance i t is believed that the exhaust fan control should be modulating as opposed to on-off. Because an exhaust fan w i l l be adversely affected by the wind, a windshield is recommended.

2-3.3 Air Supply Source Location.

2-3.3.1 The supply a i r intake should be separated from a l l building exhausts, outlets From smoke shafts and roof smoke and heat vents, open vents from elevator shafts and other building openings that might expel smoke from the building in a f i r e . This separation should be as great as is pract ical ly possible. Because hot smoke rises, consideration should be given to locating supply a i r intakes below such c r i t i ca l openings. However, outdoor smoke movement that might result in smoke feedback depends on location of the f i r e , location of points of smoke leakage from the building, wind speed and direction, and the temperature difference between the smoke and the outside a i r . At present, too l i t t l e information is available about such outdoor smoke movement to warrant general recommendations Favoring ground level intakes rather than roof- level intakes.

2-3.3.2 With any stairtower pressurization System, there is a potential for smoke feedback into the pressurized stairtower from smoke entering the stairtower through the pressurization fan intake. Therefore, the capabil i ty of automatic shutdown in such an event should be considered.

2-3.4 Air Supply Fans.

2-3.4.1 Propeller Fans.

(a) Simple single point injection systems such as that i l lustrated in Figure 2-3.¢.I may use a roof- or exterior wall-mounted propeller fan. The use of propeller fans without windshields is not recommended because of the extreme effect wind can have on the performance of such fans.

Propeller Fan

Figure 2-3.4.1 Stairtower Pressurization by Roof-Mounted Propeller Fan.

(b) These systems may also use a propeller fan mounted on the roof or exterior wall of the stairtower.

(c) One major advantage of propeller Fans is that they have a re la t ive ly Flat pressure reponse curve with respect to varying Flow. Thus, they quickly respond to a i r f low changes in the stairtower as doors are opened and closed without major pressure Fluctuations. A second advantage is that they are less costly than other types of Fans ~nd may provide adequate smoke control with lower installed costs.

(d) Propeller Fans mounted on walls pose the greatest susceptability to the adverse affects o f wind pressures. The adverse affect w i l l be maximum when wind direction is in direct opposition to the fan a i r Flow, resulting in a lower intake pressure and thus s ign i f icant ly reducing Fan effectiveness. Winds which are variable in intensity and direction also pose a detrimental effect on the a b i l i t y of the system to maintain control over the stairwel l s tat ic pressure.

2-3.4.2 Other Types of Fans. Other single inject ion systems and multiple injection systems may require the use of a centrifugal or in- l ine axial Fan to overcome the increased resistance to flow in the supply ductwork to the stairtower.

2-3.5 Single and Multiple Injection.

2-3.5.1 Single Injection.

(a) A single injection system is one that has pressurization a i r supplied to the stairtower at one location. The most common injection point is at the top as i l lustrated in Figure 2-3.5.1(a).

Centrifugal ~ . , - - - r - - -J Fan ~_~

-<

Roof Level

Figure 2-3.5.1(a) Stairtower Pressurization by Top Injection.

119

(b) Single inject ion systems can f a i l when a few doors are open near the a i r supply inject ion point. All of the pressurization a i r can be lost through these open doors, and the system wi l l then f a i l to maintain posit ive pressures across doors further From the inject ion point.

(c) Because a ground level stairtower door is l i ke l y to be in the open position much of the time, a single bottom injection system is especially prone to fa i lu re . Consideration of th is 'spec i f i c s i tuat ion as well as overall careful design analysis is required for a l l single bottom inject ion systems, and for a l l other single injection systems For stairtowers in excess of 100 f t in height.

2-3.5.2 Multiple In ject ion.

(a) Figures 2-3.5.2(a) and 2-3.5.2(b) are two examples of many possible multiple inject ion systems that can be used to overcome the l imi tat ions of single inject ion systems. The pressurization fans can be located at ground level , roof level , or at any location in between.

Level ~

l ooc,

- - ~ ~ ~ - - - ~ u c t

Figure 2-3.5.2(a) Stairtower Pressurization by Multiple Inject ion With the fan

Located at Ground Level.

~ / C e n t d f u g a l

uc,

_ < UIf

~~ Duct Figure 2-3.5.2(b) Stairtower Pressurization by Multiple Inject ion With Roof-Mounted Fan.

(b) In Figures 2-3.4(a) and 2-3.4(b), the Supply duct is shown in a separate shaft. However, systems have been bu i l t that have eliminated the expense of a separate duct shaft by locating the supply duct in the s ta i r enclosure i t s e l f . Care needs to be taken so that the duct does not reduce the required ex i t width or become an obstruction to orderly building evacuation.

(c) Many multiple injection systems have been bu i l t with supply a i r injection points on each f loor . These represent the ultimate in preventing loss of pressurization a i r through a few open doors; however, that many inject ion points may not be necessary. For designs with injection points more than three stories apart, the designer should use a computer analysis such as the one in the ASHRAE publication "Design OF Smoke Control Systems for Buildings". This is to assure that loss of pressurization ai r through a few open doors does not lead to substantial loss of stairtower pressurization.

2-3.6 Vestibules. Stairtowers which do not have vestibules can be pressurized adequately using currently available techniques. Some buildings are constructed with vestibules because of building code requirements. These vestibules may be ei ther nonpressurized or pressurized.

(a) Nonpressurized Vestibules. Stairtowers which have non-pressurized vestibules may have applications in exist ing buildings. With both vestibule doors open, the two doors in series provide an increased resistance to a i r f low compared to a single door. This wi l l reduce the required air f low through the door to produce a given pressure in the stairtower. This subject is discussed in detail in the ASHRAE publication "Design of Smoke Control Systems For Buildings".

In buildings with low occupancies, i t is possible that one of the two vestibule doors may be closed, or at least pa r t i a l l y closed, during the evacuation period. This wi l l further reduce the required ai r f low to produce a given pressure.

(b) Pressurized, Purged, or Vented Vestibules. Presently there are no means available to analyze the benefits, i f any, of pressurizing, purging or exhausting vestibules on the stairtower pressurization system. \ 2-3.7 Fire Floor Exhaust. Exhaust of the f i r e f loor can be used to improve the performance of the stairtower pressurization. A benefit of this system is to reduce the pressure on the f i r e f loor , thus increasing the pressure difference across the stairtower door. This system may or may not be a part of the zoned smoke control system. I t should discharge to the outside of the building and may be ei ther Fan powered or non-fan powered depending on the part icular building conditions. Engineering analysis of the stack and wind effects should be performed before considering this concept.

2-4 Elevator Smoke Control.

2-4.1 Elevator hoistways have proven to be a readi ly available conduit for movement of smoke throughout buildings in past f i res. This is because the elevator doors have not been t igh t f i t t i n g and elevator hoistways have been provided with openings in the top. The building stack effect has provided the driving force which has readi ly moved smoke into and out of the loosely constructed elevator hoistways. Several methods of correcting this problem have been proposed and investigated. These include:

(a) Exhaust of the f i r e f loor .

(b) Pressurization of elevator lobbies.

(c) Construction of smoketight elevator lobbies.

(d) Pressurization of the elevator hoistway.

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2-4.2 These methods have been employed either singly or in combination. However, their application to a part icular project should be closely evaluated. The open vent at the top of the elevator hoistway should be eliminated for elevator smoke control systems.

2-4.3 Fires have shown the tendency of smoke to migrate into elevator hoistways. Therefore, the use of elevators for egress purposes has not been favored. Research is currently underway to determine the f e a s i b i l i t y of maintaining elevator hoistways free of smoke during Fires.

2-5 Zoned Smoke Control.

2-5.1 General. The pressurized stairtowers discussed in Section 2-2 are intended to control smoke to the extent that they inhib i t smoke i n f i l t r a t i o n into the stairtower. However, in a building with just a pressurized stairtower, smoke can flow through cracks in f loors and part i t ions and through other shafts to threaten l i f e and damage property at locations remote From the f i r e . The concept of zoned smoke control discussed in this section is intended to l im i t this type of smoke movement within a building.

2-5.2 Smoke Control Zones.

2-5.2.1 Some buildings can be divided into a number of smoke control zones, each zone separated from the others by part i t ions, Floors, and doors that can be closed to inh ib i t the movement of smoke. A smoke control zone can consist of one f loor, more than one f loor , or a Floor can consist of more than one smoke control zone. Some arrangements of smoke control zones are i l lus t ra ted in Figure 2-5.2.1.

I I } Smoke ÷ Zone { - +

(a) (b)

,.1. ,.1.

,.1. ,.1. -,I- ,.1. "t- ÷

m

,.1.

: | ,.1. -i- ,.1.

Smoke Zone

+

,.1. ,.1. ,.1.

(c) (d)

+ + + + + + + + - + + + + ÷ + + + +

i Smoke Zone

(e)

Figure 2-5.2.1 Some Arrangements of Smoke Control Zones.

Notes:

In the above figures, the smoke zone is indicated by a minus sign and pressurized spaces are indicated by a plus sign. Each f loor can be a smoke control zone as in (a) and (b), or a smoke zone can consist of more than one Floor as in (c) and (d). All the nonsmoke zones in a building may be pressurized as in (a) and (c), or only nonsmoke zones adjacent to the smoke zone may be pressurized as in (b) and (d). A smoke zone can also be limited to a part of a f loor as in (e).

2-5.2.2 In the event of a f i r e , pressure differences and airflows produced by mechanical fans can be used to l im i t the smoke spread to the zone in which the f i r e in i t iated. The concentration of smoke in this smoke zone may render i t untenable. Accordingly, in zoned smoke control systems building occupants should evacuate the smoke zone as soon as possible af ter f i r e detection.

2-5.2.3 Smoke control zones should be kept as small as practicable so that movement of people from them can be readily achieved and that the quantity of a i r required to pressurize the surrounding Spaces w i l l be kept to a manageable level. However, they should be large enough so that heat buildup from the f i r e w i l l become suf f ic ient ly diluted with surrounding a i r to prevent Failure of major components of the smoke control system.

2-5.2.4 When a Fire occurs, a l l of the nonsmoke zones in the building may be pressurized as in Figures 2-5.2.1(a), (c) and (e). This system requires large quantities of outside a i r . The comments concerning location of supply a i r inlets of pressurized stairtowers (see 2-3.3) also apply to the supply a i r inlets For nonsmoke zones.

2-5.2.5 In cold climates, the introduction of large quantities of outside a i r can cause serious damage to building systems. Therefore, serious consideration should be given to emergency preheat systems which w i l l temper the incoming a i r and avoid or l im i t damage. Alternatively, pressurizing only those zones immediately adjacent to the smoke zones could be used to l imi t the quantity of outside a i r required, as in Figures 2-5.2.1(b) and (d); however, the disadvantage of this limited approach is that i t is possible to have smoke flow through shafts past the pressurized zone and into unpressurized spaces. When this alternative is considered, a careful examination of the potential smoke flows involved needs to be accomplished and determined acceptable.

2-5.2.6 Fire signals From protective signaling systems may be used For activating the appropriate zoned smoke control system(s). Such use of the protective signaling system requires that the alarm zones be arranged to coincide with the smoke control zones to avoid activation of the wrong smoke control system(s).

2-6 Combination Systems. There may be occasions where a combination of smoke control systems w i l l be operating simultaneously, e.g., a zoned smoke control system with pressurized stairtowers. When applying these systems, part icular attention needs to be given to the interrelat ion of the component systems. I t may not be suf f ic ient to take individual systems which have worked as independent systems and combine them to achieve a workable combination system. For example, an exhausted smoke zone operating in conjunction with a s ta i r pressurization system may tend to improve the performance of the s ta i r pressurization. At the same time i t may increase the pressure difference across the door causing d i f f i c u l t y in opening the door into the sta i r .

Chapter 3 Building Equipment and Controls

3-I General. I t is the intent of this recommended practice to u t i l i z e existing or conventional building equipment, with some modification, to provide building smoke control. Various types of building equipment

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wi l l be discussed; however, i t is impractical to cover a l l types. This chapter provides general information on equipment and controls, and provides guidelines which can be used to adapt the majority of systems encountered.

3-2 Heating, Vent i lat ing, and Air Conditioning Equipment.

3-2.1 HVAC equipment normally provides a means of supplying, returning, and exhausting a i r from a space. The HVAC equipment may be located within the space, within adjacent spaces, or within remote mechanical equipment rooms. Most HVAC equipment can be adapted for zoned smoke control.

3-2.2 I t is necessary to have the capabi l i ty of providing adequate outside a i r for supply so that suf f ic ient d i f fe ren t ia l pressures may be achieved to prevent migration of smoke into uninvolved areas. Mechanical exhaust to the outside From the smoke zone is also necessary. Some HVAC systems have this capabi l i ty without need For modification. When supply and return are interconnected as part of normal HVAC operation, smoke dampers need to be provided For separating the supply and exhaust during smoke control operation.

3-2.3 Various types and arrangements of air-handling systems are commonly used in d i f ferent types of buildings. Some typical types follow.

3-2.3.1 Individual Floor Units. Individual a i r handling units serving one Floor or part of a f loor are a common design approach. These HVAC units may or may not have separate return/exhaust Fans. Outdoor a i r may be supplied to each air-handling unit via one of the following:

(a) Exterior louvers and dampers.

(b) A common duct system having a variable speed suppy fan.

(c) Individual variable speed supply Fans.

Units may be applied to smoke control i f su f f i c ien t outside a i r and exhaust a i r capabi l i ty is available.

3-2.3.2 Central System. Some buildings u t i l i z e centralized HVAC equipment in main mechanical areas which serve multiple Floors within the building. HVAC systems of this type may require f i r e and smoke shaft dampering to provide exhaust of the f i r e f loor and pressurization of the adjacent f loors with outside a i r . Since these central fans may be of large capacity, care must be taken in designing systems to include a means to avoid excessive pressures within the duct system to prevent rupture, collapse, or other damage. A means must be provided to control pressures within exitways and corridors which could inh ib i t doors From being opened or closed.

3-2.3.3 Pan/Coil Units and Water Source Heat Pump Units. These types of a i r handling units are often located around the perimeter of a building f loor to condition the perimeter zones. Since the fan/coi l and water source heat pump units are comparatively small in outside a i r capacity and are sometimes d i f f i c u l t to reconfigure for smoke control purposes, they should be excluded from performing smoke control functions. Units within the smoke zone should be shut down when the zone is to be negatively pressurized.

The fan/coi l and water source heat pump units are sometimes used in combination with larger central HVAC equipment or individual in te r io r zone a i r handling units. The zone smoke control Functions should be provided by the larger central or in ter io r zone a i r handling units.

3-2.3.4 Induction Units. Induction type air-handling units located around the perimeter of a building are primari ly used tO condition the perimeter zone of older mult istory structures. A central HVAC system supplies

high pressure heated or cooled a i r to each perimeter induction unit. Room a i r is then induced into the induction unit , mixed with the primary a i r from the central HVAC system and discharged into the room.

Induction units within the smoke zone should be shut down or should have the primary a i r closed o f f .

3-2.3.5 Dual Duct and Multi-Zone Systems. Units used in both of these types of systems have cooling and heating coils in them, each in a separate compartment or deck.

Dual duct systems have separate hot and cold ducts connected between the decks and mixing boxes which mix the a i r supplied to the space served. For high pressure systems the mixing boxes also reduce the system pressure.

Multi-zone systems mix heated and cooled a i r at the unit and supply the mixture through low pressure ducts to each space.

Smoke control should be achieved by supplying maximum a i r to areas adjacent to the smoke zone. This should be accomplished using the cold deck because i t is usually sized to handle larger a i r quantit ies. For the Smoke zone, supply fans should be shut o f f .

3-2.3.6 Variable Air Volume Systems. A variable a i r volume (VAV) system typ ica l l y supplies central cooling only. Individual areas served by the system usually have terminal reheat provisions or other sources of heating (e.g., baseboard or cabinet heaters).

VAV systems vary the quantity of cold a i r supplied to the occupied space based on actual space demands. Some VAV systems bypass supply a i r to the return a i r in le t of the fan to reduce supply a i r volumes and resultant pressure to avoid fan or ductwork damage. In the smoke control mode, such bypasses must be closed. For smoke control, the VAV system fan and terminal unit controls should be configured to supply maximum volume of outside a i r to pressurize spaces i f su f f ic ient a i r is available. I t is possible to achieve smoke control with the VAV system supplying minimal a i r , but care must be taken to assure that adequate pressure is developed in the space.

3-2.3.7 Fan-Powered Terminals. Some variable a i r volume systems vary the quantity of cold a i r supplied to Fan powered constant volume terminal units. These terminal units consist of a constant volume fan For a i r c i rculat ion within the occupied space and heating coils to maintain the desired space temperature. In the smoke control mode, these terminal uni t fans serving the smoke zone should be shut o f f . Terminal unit Fans serving smoke control zones adjacent to the smoke zone may continue to operate normally.

3-2.3.8 Mixed Systems. Combinations of the examples above are sometimes used, especially for building areas being altered for use other than o r ig ina l l y intended. Care must be exercised in the application of d i f ferent terminal units or variable volume systems as to the i r ef fect on zoned smoke control. Designs must be based on the capabi l i ty of system configurations to achieve posit ive or negative pressures as needed for smoke control.

3-2.4 Venti lat ion Systems. In certain instances, specialized systems with no outside a i r are used For primary cooling and heating. These include self-contained a i r conditioners, radiant panel systems and computer room units. Since building codes require vent i la t ion For a l l occupied locations, a separate system for providing outside a i r is needed. This system may be used for smoke control although the quantity of a i r provided may not be adequate for f u l l pressurization.

3-2.5 Special Use Systems. Laboratories, animal f a c i l i t i e s , some hospital Fac i l i t ies and other unusual occupancies use once-through outdoor a i r systems to avoid contamination and may have special f i l t r a t i o n and

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pressurization requirements. These special use systems may be suitable for a smoke control application. Care needs to be exercised to avoid contamination of bacteria-free areas, experiments, processes, and similar areas.

3-3 Smoke Dampers. Smoke dampers used for protection of openings in smoke barriers or used as safety related dampers in engineered smoke control systems should be classif ied and labeled in accordance with UL S5SS, Standard for Leakage Rated Dampers for Use in Smoke Control Systems.

3 -4 Controls.

3-4.1 Coordination. The control system design should f u l l y coordinate the smoke control logic interlocks, and interrelat ionship among the Fire protective signaling system, HVAC system, smoke control system, and any other related systems.

3-4.2 HVAC System Controls.

3 - 4 . 2 . 1 Operating controls of the HVAC system should be designed or modified to accommodate the smoke control mode, which must have the highest p r i o r i t y over a l l other control modes.

3-4.2.2 Various types of control systems are commonly used for HVAC systems. These control systems u t i l i ze pneumatic, e lec t r ic , electronic and programmable logic based control units. All of these control systems can be adapted to provide the necessary logic and control sequences to configure HVAC systems For smoke control. Programmable electronic logic ( i . e . microprocessor) based control units, which control and monitor HVAC systems as well as provide other building control and monitoring functions, are readi ly applicable for providing the necessary logic and control sequences for an HVAC system's smoke control mode of operation.

3-4.3 Smoke Control System Activation and Deactivation. Smoke control system activation is the i n i t i a t i on of the operational mode of a smoke control system. Deactivation is the cessation of the operational mode of the smoke control system. Smoke control systems should normally be activated automatically, however, under certain circumstances, manual act ivat ion may be appropriate. Under ei ther automatic or manual act ivat ion, the smoke control system should be capable of manual override.

3 - 4 . 3 . 1 Automatic act ivat ion (or deactivation) includes al l means whereby a specif ic f i r e detection device or combination of devices causes activat ion of one or mere smoke control systems without manual intervention. For purposes of automatic act ivat ion, " f i r e detection devices" include automatic devices such as smoke detectors, waterflow switches, and heat detectors.

3-4.3.2 Manual act ivat ion (or deactivation) covers a l l means whereby an authorized person activates one or mere smoke control systems by means of controls provided for the purpose. For purposes of manual activation, the location of the controls may be at a controlled device, at a local control panel, at the building's main control center, or at the f i r e f ighters central control stat ion. The specif ic location(s) should be as required by the authori ty having jur isd ic t ion. Manual f i r e alarm pull stations should generally not be used to activate smoke control systems, other than stairtower pressurization systems, because of the l ikel ihood of a person signaling an alarm from a stat ion outside the smoke zone of f i r e origin.

3-4.3.3 Response Time. Smoke control system activation should be in i t ia ted immediately af ter receipt of an appropriate automatic or manual activation command, Smoke control systems should activate individual components (dampers, fans, etc.) in the sequence necessary to prevent physical damage to the fans, dampers, ducts, and other equipment. The total response time for individual components to achieve the i r desired state or operational mode should not exceed the following time periods:

(a) Fan operation at the desired state 60 seconds

(b) Completion of damper travel 75 seconds

3-4.3.4* Fire Fighters Smoke Control Station.

(a) The f i r e f ighters smoke control stat ion (FSCS), when required, should provide f u l l monitoring and manual control capabi l i ty over a l l smoke control systems and equipment.

(b) The FSCS should have the highest p r i o r i t y control over a l l smoke control systems and equipment. Where manual controls are also provided at other building locations for control of smoke control systems, the control mode selected from the FSCS should prevai l . FSCS control should override or bypass other building controls such as Hand-Off-Auto and Start/Stop switches located on fan motor control lers, freeze detection devices, and duct smoke detectors. FSCS control should not override or bypass devices and controls which are intended to protect against e lectr ical overloads, provide for personnel safety, and system damage. These include overcurrent protection devices, electr ic disconnect switches, high l imi t s tat ic pressure switches, and combination fire/smoke damper closure control that would preclude that response to heat beyond the required UL 33, Heat Responsive Links for Fire-Protection Service, heat responsive l ink or UL SSSS, Leakage Rated Dampers for Use in Smoke Control Systems, operator/actuator degradation temperature classification.

Exception: The FSCS fan control capabi l i ty need not bypass switches located on motor control lers of non-dedicated smoke control system fans, when:

( I ) Such fan motor control lers are located in mechanical or electr ical equipment rooms, or other areas generally accessible only to authorized personnel, and

(2) The use of such a motor contro l ler switch to turn a fan on or o f f wi l l ul t imately cause a trouble annunciation at the bui lding's main control center.

(c) The f i re f ighters smoke control stat ion should contain a building diagram which c lear ly indicates the type and location of a l l smoke control equipment (fans, dampers, e tc . ) . The building areas affected by the equipment should also be c lear ly indicated.

(d) The actual status of the systems and equipment which are activated or are capable of act ivat ion for smoke control, should be c lear ly indicated at the f i r e f ighters smoke control stat ion.

(e) Status indication should be provided for on and o f f status of each individual fan having a capacity in excess of 2000 CFM and used for smoke control. "ON" status should be sensed by d i f fe ren t ia l pressure as proof of air f low. Additional indications such as damper position may be provided where warranted by the complexity of the system.

3-4.4 Controls for Stair Pressurization Systems.

3-4.4.1 The c r i te r ia for act ivat ion of s ta i r pressurization systems should be as follows:

(a) Automatic Activation. Operation of any zone of the building protective signaling system should cause al l s ta i r pressurization fans to s tar t . In l imited instances, i t may be desirable to pressurize only some stairtowers due to part icular building configurations and conditions. A smoke detector should be provided in the a i r supply to the pressurized stairtower. Upon detection of smoke, the supply fan(s) should be stopped.

(b) Manual Activation. Manual act ivat ion and deactivation control capabi l i ty over the s ta i r pressurization systems should be provided at the FSCS we well as at the bui lding's control center. In addit ion, the FSCS should have the capabi l i ty to override the automatic shutdown of a s ta i r pressurization fan upon smoke detection, in accordance with proper judgment of the best course of action.

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3-4.5 Controls for Zoned Smoke Control Systems.

3-4.5.1 The c r i t e r i a fo r activation of zoned smoke control systems should be as follows.

(a) Automatic Activation.

( I ) An automatic detection system may be used to automatically activate a zoned smoke control system. The smoke detection system may be of l imited coverage having spacing greater than 900 sq f t per detector provided that the smoke detectors are located so as to detect smoke before i t leaves the smoke zone. The location of smoke detectors and the zoning of the detectors needs to be careful ly analyzed to achieve a smoke detection system which w i l l re l iab ly indicate the correct smoke zone.

Automatic actuation of a zoned smoke control system, which is designed to exhaust the f i r e area and supply a i r to other areas, should be given careful consideration before being undertaken because of the possib i l i ty of activation of a detector outside the zone of f i r e origin.

(2) A waterflow switch or heat detector serving the smoke zone may be used to activate the zoned smoke control system when piping and wiring of such devices coincide with the smoke control zone.

(b) Manual Activation.

(I Zoned smoke control systems should not be activated from manual stations on the building protective signaling systems. There is no assurance that the manual station is located in the smoke zone. These stations may be used to cause doors on smoke zones to close to complete the barriers to smoke movement prior to system activation.

(2) Key operated manual switches which are located within a smoke zone and which are clear ly marked to ident i fy their function, may be used to manually activate the zone's smoke control system. When a FSCS is provided, zoned smoke control systems should also be able to be manually activated from the FSCS, by switches which are c lear ly marked to ident i fy the zone and Function. In addition, when the building is provided with a main control center, zoned smoke control systems should also be able to be manually activated From the building's main control center.

Note: Extreme care should be exercised when selecting a manual-only activation to assure that suitably trained personnel are available 24 hours per day, every day. I f this cannot be guaranteed, an automatic system with manual backup should be used.

3-4.5.2 Sequence of Control and Pr io r i t i es . The automatic and manual activation (or deactivation) of zoned smoke control systems should be subject to the following sequences of control and p r io r i t i es .

(a) Automatic Activation. Automatic activation of systems and equipment fo r zoned smoke control should have the highest p r i o r i t y over a l l other sources of automatic control within the building. Where equipment used for smoke control is also used for normal building operation, control of this equipment should be preempted or overridden as required for smoke control. This equipment includes a i r supply/return fans and dampers Subject to automatic control according to building occupancy schedules, energy management, or other purposes. The Following controls should not be automatically overridden:

(1) Static pressure high l imi ts.

(2) Duct smoke detectors on supply a i r systems.

(b) Manual Activation and Deactivation. Manual activation or deactivation of zoned smoke control systems and equipment should have p r i o r i t y over automatic activation of smoke control Systems &nd equipment, as well as over a l l other sources of

automatic control within the building. Where equipment used for zoned smoke control is subject to automatic activation in response to an alarm from an automatic f i r e detector of a protective signaling system, or where such equipment is subject to automatic control according to building occupancy schedules, energy management strategies, or other non-emergency purposes, such automatic control should be pre-empted or overriden by manual activation or deactivation of the smoke control equipment. Manual controls provided speci f ica l ly fo r this purpose should be clear ly marked as to the zone and Function served. Manual controls which are shared for both smoke control functions and other building purposes, as in a building's main control center, should Fully cover the smoke control funct ional i ty in the control center operational documentation.

3-4.5.3 Sequence. Separate smoke control systems should be activated in a specific overall sequence to ensure maximum benefit and minimize any damage or undesirable effects on ducts or equipment.

3-4.5.4 Schedule. Each d i f ferent smoke control system configuration should be f u l l y defined in a schedule format which includes, but is not limited to, the following parameters:

{a) Fire zone in which a smoke control system automatically activates.

(b) Type of signal which activates a smoke Control system such as sprinkler waterflow or smoke detector.

(C) Smoke zone(s) where maximum mechanical exhaust to the outside is implemented and no supply a i r is provided.

(d) Positive pressure smoke control zone(s) where maximum a i r Supply is implemented and no exhaust to the outside is provided.

(e) Fan(s) "ON" as required to implement the smoke control system. Multiple speed fans should be further noted as "FAST" or "MAX. VOLUME" to assure that the intended control configuration is achieved.

( f ) Fan(s) "OFF" as required to implement the smoke control system.

(g) Damper(s) "OPEN" where maximum a i r Flow must be achieved.

(h) Damper(s) "CLOSED" where no a i r flow should take place.

( i ) Auxi l iary functions may be required, to achieve the smoke control system configuration, or be desirable in addition to smoke control. Changes or override of normal operation stat ic pressure control set points should also be indicated i f applicable.

3-4.5.5 Automatic Response to Multiple Signals.

In the event that signals are received from more than one smoke zone, the System should continue automatic operation im the mode determined by the First signal received.

3-5 Energy Management. Energy management systems, par t icu lar ly those which cycle supply, return, and exhaust fans for energy conservation should be overridden when their control or operation is in conf l ic t with a smoke control mode. Since smoke control is an abnormal but c r i t i ca l mode of operation, i t should take p r i o r i t y over a l l energy management and other nonemergency control modes.

3-6 Materials.

3-6.1 Materials used for systems providing smoke control should conform to NFPA 9OA, Standard for the Insta l lat ion of Air Conditioning and Ventilating Systems, and other applicable NFPA documents.

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3-6.2 Duct materials should be selected and ducts designed to convey smoke, withstand additional pressure (both posit ive and negative) by the supply and exhaust fans when operating in a smoke control mode, and maintain the i r structural i n teg r i t y during the period for which the system should operate.

3-6.3 Special high temperature ratings for smoke exhaust fans wi l l not normally be necessary.

3-7 Electr ic Services Ins ta l la t ion .

3-7.1 All e lectr ical insta l lat ions should meet the requirements of NFPA 70, National Electr ical Code.

3-7.2 Normal electr ical power serving a i r conditioning systems wi l l generally have su f f i c ien t r e l i a b i l i t y for nondedicated zoned smoke control Systems.

3-7.3 Standby power should be considered for dedicated smoke control systems and the i r control systems.

Chapter 4 Testing

4-I Introduction.

4 - I . | Absence of a consensus agreement for a testing procedure and acceptance c r i t e r i a has h i s to r i ca l l y created numerous problems at time of system acceptance, including delays in obtaining a ce r t i f i ca te of occupancy.

I t is recommended that the building owner and building designer share the i r objectives and design c r i t e r i a for smoke control with the authori ty having ju r isd ic t ion at the planning stage of the project. The design c r i t e r i a should include a procedure for acceptance test ing.

Contract documents should include operational and acceptance test ing procedures so that a l l parties - designer, insta l lers , owner, and authori ty having ju r isd ic t ion - have a clear understanding of the system objectives and the testing procedure.

4-1.2 This chapter provides recommendations for the testing of smoke control systems. Each system should be tested against i ts specific design c r i t e r i a . The test procedures described herein have been divided into three categories:

(a) Component systems test ing.

(b) Acceptance testing.

(c) Periodic testing and maintenance.

4-2 Component Systems Testing.

4-2.1 General. The intent of component systems test ing is to establish that the f inal ins ta l la t ion complies with the specified design, is functioning properly, and is ready for acceptance testing. Responsibil ity for testing should be clear ly defined pr ior to component systems test ing.

4-2.2 Prior to testing, the party responsible for this test ing should ver i fy completeness of building construction, including the following architectural features:

(a) Shaft in tegr i ty .

(b) Fire stopping.

(c) Doors/closers.

(d) Glazing.

(e) Part i t ions and cei l ings.

4-2.3 The operational testing of each individual system component should be performed as i t is completed during construction. These operational tests w i l l normally be performed by various trades before interconnection is made to integrate the overall smoke control system. I t should be cer t i f ied in wri t ing that each individual system component's ins ta l la t ion is complete, and the component is functional. Each component test should be ind iv idual ly documented including such items as speed, voltage, and amperage.

4-2.4 Because smoke control systems are usually an integral part of building operating systems, testing should include the following subsystems to the extent that they af fect the operation of the smoke control System:

(a) Fire protective signaling system (see NFPA 72H, Guide For Testing Procedures for Local, Auxi l iary, Remote Station and Proprietary Protective Signaling Systems).

(b) Energy management system.

(c) Building management system.

(d) HVAC equipment.

(e) Electrical equipment.

( f ) Temperature control system.

(g) Power sources.

(h) Standby power.

( i ) Automatic suppression systems.

( j ) Automatic operating doors and closures.

(k) Dedicated smoke control systems.

(1) Nondedicated smoke control systems.

(m) Emergency elevator operation.

4-3 Acceptance Testing.

4-3.l The intent of acceptance testing is to demonstrate that the f inal integrated system ins ta l la t ion complies with the specified design and is Functioning properly. One or more of the following should be present to grant acceptance:

Ca) Authority having jur isd ic t ion.

(b) Owner.

(c) Designer.

All documentation from operational testing should be available For inspection.

4 -3 .2 Test Equipment.

(a) Calibrated instruments to read pressure difference - d i f fe ren t ia l pressure gauges, inclined water manometers, or electronic manometer (instrument ranges 0-.25 in. w.g. and 0-.50 in. w.g. with 50 f t of tubing).

(b) Spring scale (fisherman's scale).

(c) Anamometer.

(d) Flow measuring hood (optional).

(e) Door wedges.

( f ) Tissue paper ro l l ( for indicating direction of a i r f low).

(g) Clipboard and paper for recording data.

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(h) Signs indicating that a test of the smoke control system is in progress and that doors shall not be opened (or closed).

( i ) Several walkie-talk ie radios have proven very useful to coordinate equipment operation and data recording.

4-3.3 Testing Procedures. The acceptance testing should consider inclusion of the following procedures.

4-3.3.1 Prior to beginning acceptance testing, a l l building equipment should be placed in the normal operating mode, including equipment that is not used to implement smoke control such as t o i l e t exhaust, elevator shaft vents, elevator machine room Fans, and similar systems.

4-3.3.2 Wind speed, direction and outside temperature should be recorded on each test day.

4-3.3.3 I f standby power has been provided For the operation of the smoke control system, the acceptance testing should be conducted while on both normal and standby power. Disconnect the normal building power at the main service disconnect to simulate true operating conditions in this mode.

4-3.3.4 The acceptance testing should include demonstrating that the correct outputs are produced for a given input For each control sequence specified. Consideration should be given to the following control sequences, so that the complete smoke control sequence is demonstrated:

(a) Normal mode.

(b) Automatic smoke con t ro l mode For f i r s t a larm.

(c) Manual override of normal and automatic smoke con t ro l modes.

(d) Return to normal.

4-3.3.5 I t is acceptable to perform acceptance tests for the f i r e protective signaling system in conjunction with the smoke control system. One or more device c i rcui ts on the Fire protective signaling system may in i t i a te a single input signal to the smoke control system. Therefore, consideration should be given to establishing the appropriate number of i n i t i a t i ng devices and in i t i a t i ng device c i rcu i ts to be operated to demonstrate the smoke control system operation.

4-3.3.6 Much may be accomplished to demonstrate smoke control system operation without resorting to demonstrations which use smoke or products which simulate smoke. Where the authority having jur isd ic t ion requires such demonstrations, they should be based on objective c r i te r ia .

4-3.4 Stairtower Pressurization Systems.

4-3.4.1 With a l l building HVAC systems in normal operation, measure and record the pressure difference across each stairtower door while the door is closed. After recording the pressure difference across the door, measure the Force necessary to open each door, using a spring type scale. Establish a consistent procedure For recording data throughout the entire test, such that the stairtower side of the doors w i l l always be considered as the reference point, (0 PSI) and the f loor side of the doors w i l l always have the pressure difference value (positive i f higher than the stairtower and negative when less than the stairtower). Since the stairtower pressurization system is intended to produce a positive pressure within the stairtower, a l l negative pressure values recorded on the Floor side of the doors are indicative of potential a i r flow into the Floor.

4-3.4.2 Verify the proper activation of the stairtower pressurization system(s) in response to a l l means of activation, both automatic and manual, as specified in the contract documents. Where automatic activation is

required in response to alarm signals received from the building's protective signaling system, each separate alarm signal should be in i t ia ted to ensure that proper automatic activation occurs.

4-3.4.3 With the stairtower pressurization system activated, measure and record the pressure difference across each stairtower door with a l l doors closed.

4-3.4.4 With the stairtower pressurization system activated, use a spring scale to measure, and then record, the force needed to open one selected door. With the i n i t i a l door held in the open position, measure and record the pressure difference across each remaining closed stairtower door. After recording the pressure difference across each closed door, measure the Force necessary to open each door, using a spring type scale. Use the same procedure as established in 4-3.4.1 to record data throughout the entire test. The local code and contract documents should be followed regarding the door to be opened For this test.

4 -3 .4 .5 With the s t a i r t o w e r p r e s s u r i z a t i o n system a c t i v a t e d , open the requ i red a d d i t i o n a l doors, one at a t ime, and measure and record the pressure d i f f e r e n c e across each remaining c losed s t a i r t o w e r door a f t e r the opening o f each a d d i t i o n a l door. AFter record ing the pressure difference across each closed door, measure the force necessary to open each door, using a spring type scale. Use the same procedure as established in 4-3.4.1 to record data throughout the entire test. The loca l code and con t rac t documents requi rements should be Fol lowed regard ing the number and l o c a t i o n o f a l l doors which need to be opened For t h i s t e s t . I t is suggested tha t a minimum o f th ree doors be used, w i t h the ground f loor door as the First door to be open.

4-3.4.6 With the stairtower system activated, and a l l required doors open as covered in 4-3.4.5, determine and record the direction of a i r flow through each of the open doors. This can be done by a small amount of smoke at the open doorway or by temporarily securing a G Ft long str ip of tissue to the top of the door frame. IF veloci ty measurements are required, a door opening traverse needs to be performed with the door f u l l y open.

4-3.5 Zoned Smoke Control System.

4-3.5.1 Verify the exact location of each smoke control zone and the door openings in the parameter of each zone. ( I f the plans do not speci f ica l ly ident i fy them, the f i r e protective signaling system in those zones may have to be activated so that any magnetically held doors w i l l close and ident i fy the zone boundaries.)

4-3.5.2 Measure and record the pressure difference across a l l smoke control zones which divide a building f loor. The measurements should be made while the HVAC systems serving the f l oo r ' s smoke zones are operating in their normal (non-smoke control) mode. The measurements should be made while a l l smoke barrier doors which separate the f loor zones are closed. One measurment should be made across each smoke b a r r i e r door or set o f doors, and the data should c l e a r l y i n d i c a t e the h igher and lower pressure s ides o f the doors.

4-3.5.3 Verify the proPer activation of each zoned smoke control system in response to a l l means of activation, both automatic and manual, as specified in the contract documents. Where automatic activation is required in response to alarm signals received from the building's protective signaling system, each separate alarm signal should be in i t ia ted to ensure that proper automatic activation of the correct zoned smoke control system occurs. Veri fy and record the proper operation of al l fans, dampers, and related equipment as outlined by the schedule(s) referenced in 3-4.5.4 for each separate zoned smoke control system.

4-3.5.4 Activate the zoned smoke control system(s) which are appropriate for each separate smoke control zone. Measure and record the pressure difference across a l l smoke barr ier doors which separate the smoke

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zone from adjacent zones. The measurments should be made while a l l smoke barr ier doors which separate the smoke zone from the other zones are f u l l y closed. One measurement should be made across each smoke barrier door or set of doors, and the data should clearly indicate the higher and lower pressure sides of the doors. Doors which have a tendency to open s l ight ly due to the pressure difference should have one pressure measurement made while held closed and another made while not held closed.

4-3.5.5 Continue to activate each separate zoned smoke control system and make pressure difference measurements as described in the preceeding paragraph. Ensure that af ter testing a smoke zone's smoke control system, i t is properly deactivated and the HVAC systems involved are returned to thei r normal operating mode pr ior to activating another zone's smoke control syste. Also ensure that a l l controls necessary to prevent excessive pressure differences are functional to prevent damage to ducts as related building equipment.

4-3.6 Other Test Methods.

4-3.6.1 General. The test methods previously described should provide an adequate means to evaluate the smoke management system's performance. Other test methods have been used h is to r i ca l l y in instances where the authority having jur isd ic t ion requires additional testing. While these test methods have limited value in evaluating certain system performance, their va l i d i t y as a method of testing a smoke management system is questionable.

4-3.6.2 Examples. Examples of other test methods that have been used are:

(a)" Chemical smoke tests.

(b) ~ Tracer gas tests.

(c)* Real f i r e tests.

4-3.7 Testing Documentation. Upon completion of acceptance testing, a copy of a l l operational testing documentation should be provided to the owner. This documentation should be available for reference for periodic testing and maintenance.

4-3.8 Owner's Manuals and Instruction. Information should be provided to the owner which defines the operation and maintenance of the system. Basic instruction should be provided to the owner's representatives on the operation of the system. Since the owner may assume beneficial use of the smoke control system upon completion of acceptance testing, this basic instruction should be completed prior to acceptance testing.

4-3.9 Partial Occupancy. Acceptance testing should be performed as a single step when obtaining a cer t i f i ca te of occupancy. However, i f the building is to be completed or occupied in stages, multiple acceptance tests may have to be conducted in order to obtain temporary cer t i f icates of occupancy.

4-3.10 Modifications. All operational and acceptance tests should be performed on the applicable part of the system upon system changes and modifications. Documentation should be updated to re f lec t these changes or modifications.

4-4 Periodic Testing.

4-4.1 Maintenance is essential to assure that, during the l i f e of the building, the smoke control system w i l l , under f i r e conditions, perform i ts intended function. Proper maintenance of the system should, as a minimum, include the periodic testing of a l l equipment such as i n i t i a t i ng devices, fans, dampers, controls, doors and windows. The equipment should be maintained in accordance with the manufacturer's recommendations. See NFPA 90A, Standard For the Instal lat ion of Air Conditioning and Ventilating Systems, For suggested maintenance practices.

4-4.2 This section describes the tests that should be performed on a periodic basis to determine that the instal led systems continue to operate in accordance with the approved design.

4-4.3 The system should be tested in accordance with the following schedule by persons who are thoroughly knowledgeable in the operation, testing, and maintenance of the systems. The results of the tests should be documented in the operations and maintenance log and made available for inspection.

4-4.3.1 Dedicated systems, Semiannually - Operate the smoke control system For each control sequence in the current design c r i t e r i a and observe the operation of the correct outputs For each given input. Tests should also be conducted under standby power, i f applicable.

4-4.3.2 Nondedicated systems, AnnUally - Operate the smoke control system for each control sequence in the current design c r i t e r i a and observe the operation of the correct output For each given input. Tests should also be conducted under standby power, i f applicable.

4-4.4 Special arrangements may have to be made For the introduction of large quantities of outside a i r into occupied areas or computer centers when outside temperature and humidity conditions are extreme. Since smoke control systems override l im i t controls such as freezestats, tests should be conducted when outside a i r conditions w i l l not cause damage to equipment and systems.

Chapter 5 Referenced Publications

(Publications referenced in Chapters l through 4 of this Recommended Practice w i l l be l isted here.)

Appendix A

This Appendix is not a part of the requirements of this NFPA document, but is included for information purposes only.

A-2-2.1 A smoke control system should be designed to maintain the minimum design pressure differences under l i ke l y conditions of stack effect or wind. The minimum design pressure differences of Table 2-I For nonsprinklered spaces are values that w i l l not be overcome by buoyancy forces of hot gases. The method used to obtain the values of Table 2-I For nonsprinklered spaces is described below. The pressure difference due to buoyancy of hot gases is calculated by the following equation:

~P 7 6 4 1]h TF

where:

~P = pressure difference due to buoyancy of hot gases in inches of water gage

To = absolute temperature of surroundings in degrees R

TF = absolute temperature of hot gases in degrees R

h = distance above neutral plane in feet

The neutral plane is a horizontal plane between the Fire space and a surrounding space at which the pressure difference between the f i r e space and the surrounding space is zero. For Table 2-I, h was conservatively selected at 2/3 of the f loor to cei l ing height, the temperature of the surroundings was selected at 70°F, the temperature of the hot gases was selected at lTO0°F, and a safety Factor of 0.03 inches water gage was used.

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EXAMPLE: Calculate the minimum design pressure difference for a ceil ing height of ]2 f t .

To = 70 + 460 = 530°R

T F 1700 + 460 = 2160°R

h = (12 ) 2/3 = 8 Ft

From the above equation AP = 0.87 inches water gage. Adding the safety factor and rounding o f f , the minimum design pressure difference is 0.12 inches water gage.

A-3-4.3.4 Example of a Fire Fighter's Smoke Control Station (FSCS).

Location and Access. The FSCS should be located in proximity to other f i r e f ighters ' systems as may be provided within the building. Means should be provided to ensure only authorized access to the FSCS. Where acceptable to the authority having jur isd ic t ion, the FSCS should be provided within a specif ic location or room, separated from public areas by a suitably marked and locked door. When located in a separate room, the room location, size, access means, and other physical design considerations should be acceptable to the authority having jur isdict ion.

Physical Arrangement. The FSCS should be designed to depict graphically the physical building arrangement, smoke control systems and equipment, and the areas served by the equipment. Following is a summary of the status indicators and smoke control capabil i ty applicable to the FSCS smoke control graphic(s).

Status Indicators should be provided for a l l smoke control equipment by p i lo t lamp-type indicators as follows:

(a) Smoke Control Fans and other c r i t i c a l operating equipment in the operating state . . . . . . . . . . . . . . . Green

(b) Smoke Control Equipment and other c r i t i ca l equipment which may have two or more states or positions such as dampers.

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Green ( i . e . , OPEN)

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Yellow ( i . e . , CLOSED)

The position of each piece of equipment should be indicated by lamps and appropriate legends. Intermediate positions ( i . e . , modulating dampers which may not be f u l l y open or f u l l y closed) may be indicated by not illuminating either of the i r p i l o t lamps.

(c) Smoke Control System or Equipment Faults . . . . . . . . . . . . . . . Amber/Orange

NOTE: Use of the positions of multiposition control switches to indicate the status of a controlled device, should not be used in l ieu of p i lo t lamp-type of status indicators as described above.

Provision for testing the p i lo t lamps on the FSCS smoke control panel(s) by means of one or more "LAMP TEST" momentary push buttons or other sel f -restor ing means should be included.

Smoke Control Capability. The FSCS should provide control capabil i ty over a l l smoke control system equipment within the building as Follows:

ON-AUTO-OFF control over each individual piece of operating smoke control equipment which can also be controlled from other sources within the building. This includes a l l stairway pressurization Fans, smoke exhaust fans, HVAC supply, return, and exhaust fans in excess of 2000 CFM, elevator shaft fans, atrium supply and exhaust Fans, and any other operating equipment used or intended for smoke control purposes.

ON-OFF or 0PEN-CLOSE control over a l l smoke control and other c r i t i ca l equipment associated with a Fire or smoke emergency and which can only be controlled from the FSCS.

OPEN-AUT0-CLOSE control over a l l individual dampers relat ing to smoke control and which are also controlled From other sources within the building.

HVAC terminal units, such as VAV mixing boxes which are a l l located within and serve one designated smoke control zone, may be controlled co l lec t ive ly in l ieu of individual ly.

HVAC unit coi l face-bypass dampers which are arranged so as to not res t r i c t overall a i r f low within the system may be exempted.

Additional control as may be required by the authority having jur isdict ion.

Control Action and Pr ior i t ies .

The FSCS control action should be as follows:

ON-0FF, OPEN-CLOSE, . . . These control actions should have the highest p r io r i t y of any control point within the building. Once issued from the FSCS, no automatic or manual control from any other control point within the building should contradict the FSCS control action.

Where automatic means is provided to interrupt normal nonemergency equipment operation or produce a specif ic result to safeguard the building or equipment ( i . e . , duct freezestats, duct smoke detectors, high temperature cutouts, temperature actuated linkage, and similar devices), such means should be capable of being overridden by the FSCS control action and the last control action aS indicated by each FSCS switch position should prevail.

AUTO. 0nly the AUTO position of each 3-position FSCS control should allow automatic or manual control action From other control points within the building. The Auto position should be the normal, nonemergency, building control position. When an FSCS control is in the AUTO position, the actual status of the device (on, o f f , open, closed) should continue to be indicated by the status indicator(s) described in the previous section.

FSCS Response Time. For purposes of smoke control, the FSCS response time should be the same as for automatic or manual smoke control action in i t ia ted from any other building control point. (Refer to "Response Time" values in the Control Systems section.)

FSCS p i lo t lamp indication of the actual status of each piece of equipment should not exceed 15 seconds af ter operation of the respective feedback device.

Graphic Depiction.

The location of a l l smoke control systems and equipment within the building should be indicated by symbols within the overall FSCS smoke control building graphic panel. All major ducts and dampers within the building which ace part of the smoke control system as well as the building areas served by the smoke control systems should be shown on the FSCS smoke control building graphic panel. Fans and dampers used for smoke control should be shown on the building graphic panel, and where appropriate, be shown connected to thei r respective ducts, with a clear indication of the direction of a i r f low.

A-4-3.6.2(a) Chemical Smoke Tests. Chemical smoke tests have achieved a degree of popularity out of proportion to the limited information they are capable of providing. The most common sources of chemical smoke are the commercially available "smoke candle" (sometimes called a smoke bomb) and the smoke generator apparatus. In this test, the smoke candle is usually placed in a metal container and ignited. The metal container is for protection From heat damage af ter igni t ion - i t does not inhib i t observation of the movement of the chemical smoke. Care needs to be exercised during observations, because inhalation of chemical smoke can cause nausea.

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This type of testing is less rea l i s t i c than real Fire testing because chemical smoke is cold and lacks the buoyancy of smoke From a Flaming Fire. Such buoyancy Forces can be su f f i c ien t l y large to overpower a smoke control system that was not designed to withstand them. Smoke From a sprinklered Fire has l i t t l e buoyancy, and so i t may be expected that such smoke movement is similar to the movement of unheated chemical smoke. This has not yet been confirmed by test data. Chemical smoke testing can ident i fy leakage paths, and such tests are simple and inexpensive to perform.

The question arises as to what information can be obtained From a cold chemical smoke test. I f a smoke control system does not achieve a high enough level of pressurization, the pressures due to hot, buoyant smoke could overcome that system. The a b i l i t y to control cold chemical smoke provides no assurance of the a b i l i t y to control hot smoke in the event of a real f i r e .

Chemical smoke is also used to evaluate the effectiveness of so called smoke "purging" systems. Even though such systems are not smoke control systems, they are closely related and so they w i l l be b r ie f l y addressed here. For example, a system that has six a i r changes per hour when in the smoke purge mode w i l l be considered. Some testing o f f i c i a l s have mistaken this to mean that the a i r is completely changed every ten minutes, and so ten minutes af ter the smoke candle is out a l l the smoke should be gone from the space. OF course, this is not what happens. In a "purging" system, the a i r entering the space mixes to some extent with the a i r and smoke in the space. I f the "purging" system is part of the HVAC system, i t has been designed to promote a rather complete degree of mixing. I f the concentration of smoke is close to uniform within the space, then the method of analysis for "purging" presented in Section 2.3 of the ASHRAE publication "Design of Smoke Control Systems for Buildings" is appropriate. Based on such perfect mixing, af ter ten minutes 37 percent of the original smoke would remain in the space.

A-4-3.6.2(b) Tracer Gas Tests. Because of the many Possibi l i t ies of error and the l imitat ions discussed below, tracer gas tests should be conducted and evaluated with a high level of professional competence. I t is not believed that tracer gas testing is appropriate For routine acceptance testing of smoke control systems.

In these tests, a constant Flow rate of a tracer gas is released in the building. Samples are collected throughout the building and are analyzed to determine possible paths of smoke movement in the event of a real f i r e . The tracer gas most commonly used is sulfur hexafluoride (SF6) because i t is nonflammable, colorless, odorless, v i r tua l l y nontoxic*, and chemically stable. These attr ibutes result in tests that do not interfere with the normal operation of the f a c i l i t y being tested. In addition, SF6 is v i r t u a l l y unused industr ia l ly , which essential ly eliminates the chance of interference From another source.

SF6 is commercially available and is stored as a l iquid at 320 psi (2.2 MPa) and 70°F (21°C). A constant flow rate of gaseous SF6 can be maintained by using a pressure regulator and a flowmeter such as a rotameter. The flowmeter should be spec i f ica l ly calibrated for SF6. Flow rates in the ranges of 2 to ]0 mL/min have been used.

*OSHA concentration l im i t of SF6 is l,O00 parts per mi l l ion (ppm) as set forth in the Federal Register, Vol. 36, No. 157, August ]3, 197]. However, in smoke control testing, concentrations generally do not exceed 2 ppm.

Tradi t ional ly , a i r samples have been collected in hypodermic syringes and analyzed in a batch mode on a gas chromatograph Fitted with an electron capture cel l and an appropriate column For separation oF SF6 From other gases. Continuous sampling using a gas chromatograph is also possible. Samples of standard concentrations of SF6 in a i r or nitrogen are commercially available For cal ibrat ion of the gas chromatrograph. Gas chromatrographs can analyze SF6 in the range of 0 to 180 parts per b i l l i on (ppb), and samples of higher concentration should be diluted For analysis. Caution should be exercised because, at high concentrations, SF6 can permeate some materials and thus contaminate any a i r samples that might contact these materials. Because of the many poss ib i l i t ies of error, the tester needs to adhere rigorously to good testing methods.

Tracer gas testing has the advantage of identi fying leakage paths and determining i f a smoke control system can control the movement of a nonbuoyant gas. Because gaseous SF6 is inv is ib le, careful selection of the locations to be sampled is important.

A major drawback to the use of tracer gas testing is, again, the lack of buoyancy in the gas, i . e . , the gas is typ ica l ly at an ambient temperature when released. To overcome this deficiency, the a i r and SF6 mixture can be heated, but caution should be exercised, because at high temperatures SF6 can degenerate into toxic components. As with chemical smoke, unheated SF6 movement is l i ke l y to be similar to that of smOke From a sprinklered f i f e , but, this has not yet been confirmed by test data.

A-4.3.6.2(c) Real Fire Tests. I t is an understatement to say that acceptance testing involving a real f i r e has obvious danger to l i f e and property because of the heat generated and the tox i c i t y of the smoke. Such a f i r e test was required by the local f i r e department fo r a pressurized stairwel l system in a eight story o f f ice building in Hamburg, Germany. At the time, no pressurized stairwel ls existed in Germany and the local authorities wanted to be sure the system would work.

The test was conducted before the in ter ior Finishes were instal led. Much of the second Floor where the Fire was located was "Fire hardened" to prevent structural damage. The f i r e load consisted of wood cribs and expanded polystyrene weighing a total of 1/3 ton (370 kg). The Fire reached a peak temperature of 1300°F (700°C), was above 750°F (400°C) for over 20 minutes, and produced large quantities of dense black smoke. Throughout the test there was no v is ib le smoke within the sta i rwel l , thus the system passed the acceptance test.

A large real f i r e l ike the one described above is the most rea l i s t i c method of testing the a b i l i t y of a smoke control system to control smoke movement. Because of the inherent danger, remote instruments should be used and construction and other ac t i v i t i es must be suspended in the building during the f i r e test.

Gas burners could be used in place of solid fuels. Such an approach would reduce the hazard of toxic gases and result in a f i r e that could be simply turned o f f rather than have to be extinguished with water. To produce v is ib le smoke, smoke candles can be placed on the burners or the gas can contain a small quantity of acetylene.

The Fire tests discussed above are obviously not warranted For smoke control system concepts that are well developed. However, i t seems reasonable that radical ly new concepts For smoke control systems should be Fire tested.

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Date post:	22-Jan-2022
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TCD-87-F Technical Committee Docu mentation

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