Lecture 4 Means of Egress

Post on 13-Nov-2014

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MEANS OF EGRESSGETTING OUT OF THE

BUILDING

THREE MAIN CATEGORIES

• EXIT ACCESS– ANY SPACE OCCUPIED OR TRAVELED ON THE WAY TO THE EXIT

• EXIT – BETWEEN THE EXIT ACCESS AND THE EXIT DISCHARGE

• EXIT DISCHARGE– BETWEEN THE EXIT AND THE PUBLIC WAY– COULD BE INDOORS OR OUTDOORS

• PUBLIC WAY – FINAL DESTINATION

• AREA OF REFUGE – SAFE SPOT

THREE MAIN CATEGORIES

EXIT ACCESS-DOORS

• MINIMUM SIZE 3068• MUST SWING IN

DIRECTION OF EGRESS TRAVEL

• MUST BE SIDE HINGED & SIDE SWINGING

• HARDWARE• FORCE• THRESHOLD

EXIT ACCESS-DOORS

• Door swing clearances

• “Latch side clearance”

EXIT ACCESS-STAIRS

• Exit Access stairs are uncommon

• Treads & Riser dimensions

• Landings• Ceiling Height• Hand & Guard

Rails

EXIT ACCESS-STAIRS

EXIT ACCESS-STAIRS

EXIT ACCESS-STAIRS

EXIT ACCESS - CORRIDORS

• SURROUNDING WALLS, FLOORS, & CEILING

• EITHER NON-RATED OR 1 HOUR RATED

• LENGTH & WIDTH LIMITED

EXIT ACCESS – AISLES

• Created by furniture or equipment

• Additional ADA accessibility clearances must be given

• Fixed seating in A1 occupancies are generally covered seperately in the codes

Exit Acess –Adjoining or Intervening Rooms

• “…direct, unobstructed, and obvious means of travel toward an exit.”

• Restrictions include storage rooms, restrooms, closets, bedrooms, locked rooms, kitches, file rooms.

• Does not apply to tenant spaces.

Exits

• End of Exit Access

• Must be fully enclosed and rated

• Codes dictate specific quantity, location and size for all exits (later)

• Four Types…..

Exits – Exterior Exit Doors

• Exception – not typically required to be fire rated.

• Simple doorway, exterior wall. Typically leads straight to exit discharge or public way.

Exits – Exit Stairs

• Most common type of exit

• Complete enclosure

• May include area of refuge

Exits –Horizontal Exits

• Typically used in Institutional occupancy classifications

Exits – Exit Passageways

• Extends an Exit

• Exit access doors can exit directly into

Exit Discharge

• Main lobby (interior – most common)

• Foyer or Vestibule (interior)

• Discharge Corridor (interior)

• Egress Court (exterior)

• Small Alley or Sidewalk (exterior)

Means of Egress CapacityHow many people can safely exit the

building in an emergency

4 Specifics to be determined

• Number of Exits

• Exit Width

• Exit Arrangement

• Travel distance

Number of ExitsOccupant Load per Story or Area Minimum No. of Exits

1-500 2

501-1000 3

Over 1000 4

Exit Widths

•Minimum door widths•Maximum door widths•More than one exit•Minimum exit discharge width•Minimum corridor width•50% percent rule

Exit Widths

Longer Aisle Accessway

12 inches +.05(x-12 feet)

Arrangementof Exits

• Remoteness = Half-diagonal rule

Arrangement of Exits

Travel Distance

“Common path of travel”

Dead-End Corridors

•Corridors vs Aisles

•20’ max or 50’ if in a sprinkled space.

Problem #2

Problem #3a. What is the total exit width

required for the telemarketing company in Space C? 175 x 0.15=26

b. What is the total exit width required for each exit stair?306 x 0.2=61

c. What is the minimum exit width required for the exit access corridor?

306 x 0.15=46

Problem #4 part b.12 inches + 0.5(x-12 feet)

12 inches + 0.5(23’-9” – 12 feet)12 inches + 0.5 (11’-9”)12 inches + 0.5 (11.75’)

12 inches +5.875” = 17.875 = 18 inches

Problem #5