8/12/2019 JK, Inc - Region III ASSP PDC

18/12/2019 JK, Inc - 8926 Kirby Drive, Houston Texas 77054 713-664-1597 [email protected]

ABSTRACT Assist with OSHA compliance for identification, evaluation,

and further implementation of control measures for limitationof occupational airborne exposure to Respirable CrystallineSilica (RCS) during:

1) Drywall installation and finishing,2) Saw cutting and drilling concrete, and3) Jackhammering concrete.

Improve compliance to applicableOSHA Standards elements andsafety and health requirements

8/12/2019 JK, Inc - 8926 Kirby Drive Houston Texas 77054 713-664-1597 [email protected] 2

FINISHER/TAPER

Criteria 1926.1153(a) Scope and Application.

This section applies to all occupationalexposures to Respirable CrystallineSilica (RCS) in construction work,except where employee exposure willremain below 25 micrograms per cubicmeter of air (25 μg/m3) as an 8-hourTime-Weighted Average (TWA) underany foreseeable conditions.

8/12/2019 JK, Inc - 8926 Kirby Drive, Houston Texas 77054 713-664-1597 [email protected] 3

OSHA 29CFR1926.1153Respirable Crystalline Silica (RCS)

1926.1153(c)(1) For each employee engaged in a task identified on Table1, the employer shall fully and properly implement the engineeringcontrols, work practices, and respiratory protection specified for thetask on Table 1, unless the employer assesses and limits the exposure ofthe employee to RCS in accordance with paragraph (d) of this section.

Table 1—Specified Exposure Control Methods When Working With

Materials Containing Crystalline Silica

Criteria Table 1 has criteria for hand-held

power saws, walk-behind saws,jackhammers, chipping tools, etc. andno specific reference for dry wall work.

Performance Option. Employer shallassess 8-hour TWA exposure for eachemployee based on any combination ofair monitoring data or objective datasufficient to accurately characterizeemployee exposures to RCS.


DRYWALL HANGER

1926.1153(d)(2)(iii) Scheduled Monitoring Option. 1926.1153(d)(2)(iii)(A) The employer shall perform initial monitoring to

assess the 8-hour TWA exposure for each employee on the basis of one ormore personal breathing zone air samples that reflect the exposures ofemployees on each shift, for each job classification, in each work area.Where several employees perform the same tasks on the same shift and inthe same work area, the employer may sample a representative fraction ofthese employees in order to meet this requirement. In representativesampling, the employer shall sample the employee(s) who are expected tohave the highest exposure to RCS.

Plan Assessments by personal

breathing zone airborne silicamonitoring and workplace fieldobservations were to be plannedfor:

➢ Two drywall installer job positions: 1. Sheetrock Installer, and

2. Finisher/Taper.

➢ Three concrete workers: 1. Remote Jackhammer Operator,

2. Drill/Core Drill Operator, and

3. Slab Saw Operator.


Plan If results of personal monitoring

indicated potential elevatedairborne exposure to RCS aboveguidelines, then proceduralchanges were to be implementedwith additional air monitoring.

Investigation of various controlmeasures and provision ofequipment recommendations aswell as assistance withdevelopment of an updatedwritten Respiratory ProtectionProgram for the Company.


MANUAL HAND SANDING

Details Substantial job site observations

of various construction tradeswere noted at several facility workareas. Specific focus was directedfor drywall installation andfinishing operations and site workpractices employed by companypersonnel and crew members.


FLOOR SWEEP

Floor Sweep Compound Use at Site

Details Appropriate data review for RCS, including airborne quartz,

results was completed for OSHA compliance determinationsespecially related to selection and use of respiratoryprotection.


DUST COLLECTION

8-Hour TWA OELs➢ OSHA Action Level (AL) =

25 ug/m3

➢ OSHA Permissible ExposureLimit (PEL) = 50 ug/m3

➢ ACGIH Threshold LimitValue (TLV) = 25 ug/m3

Monitoring Methods The validated industrial hygiene sampling

and analytical methods were: NIOSH0600 for respirable particulates using SKCaluminum cyclones, and NIOSH 7500 forcrystalline silica with lab analysis forcristobalite, quartz, and tridymite formsof RCS. Personal pumps were pre- andpost-calibrated with a primary standardand PVC filter media and processed to anaccredited American Industrial HygieneAssociation (AIHA) laboratory. Fieldblank samples were also prepared andincluded for analysis and proper QC.


Monitoring Methods TSI Q-TRAK IAQ unit for CO2, CO,

Temperature, and %RH parameters atgenerally unconditioned work sites.

3M EVM-7 Unit: EnvironmentalAssessment of Particulate Matter (PM)concentrations in mg/m3 through use ofimpactor selection of airborne size criteria:- PM10, - PM4, and - PM2.5.

Grab samples collected at project workareas during separate drywallinstallation/hanging activities, and alsofinishing/sanding operations.

Other reported data documentationincluded concentrations of CO2 and CO,and Temperature and % Relative Humidityas well as Volatile Organic Compounds(VOCs) in units of parts per billion (ppb).


Drywall Project Scope of DiscussionLocations and Study Dates:

Houston, Texas and surroundingareas (i.e. Baytown, Friendswood,and Missouri City, Texas) for newconstruction projects involvingdefined work activities for drywallinstallation and hanging as well asdrywall finishing including tapeand float application, andpredominantly surface sanding. IHmonitoring and site observationswere performed for 12 site visitsduring February, March, May,October, and November 2017.


SANDING

Drywall Project Scope of DiscussionTypes of Facilities:

Examples: school districts,colleges and university buildings,and a church.

Other construction trades/craftswere additionally performingcurrent work within the facilitiesassociated with new construction.

Specific segregated operationareas were not observed forfinishing/sanding activities.


ELECTRIC SANDER

Drywall Work Results Some results for respirable particulates did

exceed published OELs [i.e. AmericanConference of Governmental IndustrialHygienists (ACGIH) Threshold Limit Values(TLVs)] and also OSHA regulations for RCSin the Construction industry.

Site observations and notation of existingcontrol measures and current work practicesand procedures were essential for datainterpretation and project documentation.Investigation of further control options wasalso conducted in addition to provision oftechnical recommendations related toavailable equipment modifications forassistance with limitation of existingoccupational airborne exposures to RCS.

8/12/2019 JK, Inc - 8926 Kirby Drive Houston TX 77054 713-664-1597 [email protected] 13

MANUAL POLE SANDING

Drywall Work Results Use of available control measures for

dust collection resulted in decrease ofairborne RCS concentrations forinvestigated construction drywall worksite job positions.

Direct observations and assessment ofnoted variations in drywall finishingoperations at separate constructionprojects and use of source controlmeasures for dust collection indicateddecreased personal breathing zoneexposures for respirable particulates,airborne quartz concentrations, andalso calculated 8-hour Time WeightedAverage (TWA) exposures.


POLE SANDING WITH VACUUM

Drywall Work Results Representative full-shift monitoring results

confirmed greater impact for sanding workactivities, and noted pertinent effectivenessof control measures employed.

An overall combination of naturalventilation, position and use of area fans fordilution ventilation and air cooling as wellas observations of most construction crewmembers employing N95 filtering facepieces were noted.

Appropriate written program documen-tation for Client site PPE requirementsshould be confirmed.


Drywall Work Results – Monitoring Data Summary


SELECTED DATA COMPARISONS

DRYWALL HANGER:

Without Use of Controls

Number of

Data Points

Range of Respirable

Particulates (mg/M3)

Range of Quartz

Concentrations

(mg/M3)

Calculated 8-Hour

TWAs

4 0.21 – 1.1 < 0.009 – 0.04 < 0.008, 0.008,

and 0.036

5 0.08 – 0.15 < 0.009 – 0.008 0.0079

With Use of Controls

4 0.33 – 0.51 < 0.010 < 0.009

Drywall Work Results – Monitoring Data Summary


SELECTED DATA COMPARISONS

FINISHER/TAPER:

Without Use of Controls

3 0.11 – 0.26 < 0.010 < 0.008, < 0.009

2 0.73 – 1.2 0.03 – 0.05 0.016, 0.027

With Use of Controls

2 0.02 – 0.05 < 0.01 < 0.009

2 0.028 – 0.040 < 0.009 – 0.02 < 0.009, 0.019

Drywall Work Results - Graph


0

10

20

30

40

50

60

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25

µg/m

3

AIRBORNE RCS MONITORING RESULTS RELATED TO USE OF CONTROL MEASURES AT PROJECT

WORK SITES

WITHOUT

WITH

OSHA PEL

OSHA AL

DRYWALL WORK CONCLUSIONS

Exposure assessment monitoring and job positionobservations of drywall hanging and finishing operationswere addressed for various new construction work sites byIndustrial Hygiene (IH) personnel for airborne RCS datareview and interpretation.

Generally new construction projects investigated involvedextensive installation of drywall building materials withnecessary hanging on metal studs, fitting through use ofrasps or saws, tape and float of seams and surfaces,finishing, and sanding activities with visible dustparticulates generated, and work area cleaning using floor-sweep compounds.


Concrete Project Scope of DiscussionLocations and Study Dates:

Houston, Texas for newconstruction projects involvingdefined work activities for variousconcrete cutting and demolitionoperations. Standard activitiesinvolved use of various automaticand manual saws employing wetmethods and other current controlmeasures, at a minimum, andconstruction equipment operationfor an outlined project scope ofwork as directed by the Client.

IH monitoring and site observationswere performed in 2017 and 2018.


Concrete Project Scope of DiscussionTypes of Facilities:

Project observations verified useof wet methods, vacuum, anddebris collection to limit airbornebreathing zone exposures.Ambient environments providedaccess to dilution ventilation.

For segregated interiorenvironments, provision ofsupplemental ventilation wasemployed as an effective controlmeasure, and manual versusremote control equipmentoperations were investigated.


Concrete Work Results Some results for respirable particulates did

exceed published OELs [i.e. AmericanConference of Governmental IndustrialHygienists (ACGIH) Threshold Limit Values(TLVs)] and also OSHA regulations for RCSin the Construction industry.

Site observations and notation of existingcontrol measures and current work practicesand procedures were essential for datainterpretation and project documentation.Investigation of further control options wasalso conducted in addition to provision oftechnical recommendations related toavailable equipment modifications forassistance with limitation of existingoccupational airborne exposures to RCS.

8/12/2019 JK, Inc - 8926 Kirby Drive Houston TX 77054 713-664-1597 [email protected] 22

Concrete Work Results

Use of Table 1control measures fordust collectionresulted in decreaseof airborne RCSconcentrations forinvestigatedconcrete work jobpositions.


(x) Jackhammers and handheld

powered chipping tools

Use tool with water delivery

system that supplies a

continuous stream or spray

of water at the point of

impact:

-When used outdoors None APF 10

-When used indoors or in an

enclosed area

APF 10 APF 10

OR

Use tool equipped with

commercially available

shroud and dust collection

system

Operate and maintain tool in

accordance with

manufacturer's instructions

to minimize dust emissions

Dust collector must provide

the air flow recommended

by the tool manufacturer, or

greater, and have a filter

with 99% or greater

efficiency and a filter-

cleaning mechanism:

-When used outdoors None APF 10

-When used indoors or in an

enclosed area

APF 10 APF 10

Concrete Work Results

Direct observations and assessment ofnoted variations in drywall finishingoperations at separate constructionprojects and use of source controlmeasures for dust collection indicateddecreased personal breathing zoneexposures for respirable particulates,airborne quartz concentrations, andalso calculated 8-hour Time WeightedAverage (TWA) exposures.


Concrete Work Results Representative full-shift

monitoring results confirmedgreater impact for sawingwork activities, and notedpertinent effectiveness ofcontrol measures employed.

An overall combination ofnatural ventilation, positionand use of integrated waterdelivery system thatcontinuously fed water to thecutting surface was noted.


Appropriate written program documentation for Client site PPErequirements should be confirmed.

Concrete Work Results – Monitoring Data Summary


TYPE SAMPLE DESCRIPTION

TIME

(Min)

RESULTS

Respirable

Particulates

(mg/M3)Personal Core Drill Operator 388 < 0.02

TYPE

SAMPLE

DESCRIPTION

TIME

(Min)

RESULTS

Respirable

Particulates

(mg/M3)

RESULTS/%Si

Quartz

(mg/M3)

PersonalRemote Jack

Hammer Operator

339 < 0.02 0.01 [100%]

Personal Core Drill Operator 335 0.02 0.01 [50%]

Personal Slab Saw Operator 333 0.08 0.02 [29%]

CONCLUSIONS

Some personal monitoring results for airborne respirableparticulates did exceed published OELs including ACGIH TLVand OSHA PEL and AL new regulatory requirements for RCSwithout respect to considered use of respiratory protection.

Recommendation for revision of the company writtenRespiratory Protection Program (RPP) was provided to thespecific Client’s Safety Representative. Current exposuremonitoring data was used to assess employee protection andeffectiveness of control measures.


CONCLUSIONS

Investigation of further existing control measures was alsoconducted in addition to provision of technicalrecommendations related to available equipmentmodifications for assistance with limitation of existingoccupational airborne exposures to RCS.


Some Additional Resources


Silica Resource Guide for Contractors published by ASSPIndustrial Hygiene Practice Specialty, September 2019

NIOSH 7500 SILICA, CRYSTALLINE, by XRD (filterre-deposition)

OSHA - Controlling Respirable Crystalline Silica inConstruction: Handheld Power Saws (Any BladeDiameter)

https://www.youtube.com/watch?v=pfYI31pF4Ng&feature=youtu.be

OSHA - Controlling Respirable Crystalline Silica: Handheld and Stand-Mounted Drills

https://www.youtube.com/watch?v=Yzo-sZ_PSic&feature=youtu.be

OSHA - Controlling Respirable Crystalline Silica: Jackhammers and Handheld PoweredChipping Tools

https://www.youtube.com/watch?v=e2uRD2dJ8vs&feature=youtu.be

https://www.youtube.com/watch?v=pfYI31pF4Ng&feature=youtu.be

https://www.youtube.com/watch?v=Yzo-sZ_PSic&feature=youtu.be

https://www.youtube.com/watch?v=e2uRD2dJ8vs&feature=youtu.be

JAN KOEHN, M.S., CIH

JK, INC.8926 Kirby Drive

Houston, TX 77054

Phone: (713) 664-1597E-mail: [email protected]


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