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Home My WebLink About1990/12/10 Board of Appeals & Advisors Agenda Packet (2) Item 113B (1) Defmition of EXIT Exit is a continuOQs and unobstructed means of egress to a public way and shall include intervening aisles, doors, doorways, corridors, exterior exit baJco- nies, ramps, stairways, smokeproof enclosures, horizontal exits, exit passage- ways, exit courts and yards. Doors/Doorways - Corridors Exterior Exit Balconies Ramps StaÏ1ways Smokeproof Enclosures Horizontal Exits Exit Passageways Exi t Courts Yards Public Way Section 3301 (b) 1 Item 113B (2) BASIC CONCEPTS OF EXITING · Exits must be provided for all building occupants · Occupants must have control of all elements of the exiting system · Once size and number have been established, they cannot be reduced · Once level or degree of fire safety has been established, they cannot be reduced EXITING Chapter 33 2 -- --- Item 113B (3) TABLE NO. 33-A-MINIMUM EGRESS AND ACCESS REQUIREMENTS . - ~..- ~ ,... MINIMUM OF ACCESS BY ,,- TWO EXITS ~ MEANS OF A OTHER THAN RAMP OR AN ELEVATORS ARE ELEVATOR MUST REQUIRED OCCU· SE PROVIDED WHERE PANT FOR THE NUMBER OF LOAD PHYSICALLY OCCUPANTS IS FACTOR2 HANDICAPPED USE' AT LEAST (Sq,Ft.) AS INDICATED3 1. Aircraft Hangars (no repair) 10 500 Yes 2. Auction Rooms 30 7 Yes I I 3, Assembly Areas, Concen- I trated Use (wilhout fixed seats) 50 7 Yes" ~ Auditoriums Churches and Chapels Dance Floors Lobby Accessory to Assembly Occupancy Lodge Rooms Reviewing Stands Stadiums \\'airing: Area SO 3 YesJ ~ ~. Assembly Areas, Less-con· centrated Use 50 15 Yes': ~ b Conference Rooms Dining Rooms Drinking Establishments Exhibit Rooms Gymnasiums Lounges Stages 5, Bowling Alley (assume no I occupant load for bowling lanes) 50 " Yes I I , 6, Children's Homes and Homes for the Aged 6 80 Ycs~ èO I 1'~S' 7 _ Classrooms 50 I 8. Courlrooms 50 40 Yes I 9. Dormitories 10 50 I Yesì 10, Dwellings 10 300 :--10 11. Exercising Rooms 50 50 Yes 12, Garage, Parking 30 200 Yes' 13, Hospitals and Sanitaríums- Nursing Homes 6 80 Yes 10 200 I Ycs1i1 , 14. Hotels and Apartments ] 5. Kitchen--Commcrcial 30 èOO :-';0 ! 16 Library Rcadinp: Room 50 50 ì'...."J i 30 50 Yo.:-; I 17. Locker Rooms I 18. :">lalls (see Chapter 56) - i - - i 5 Item 113B (4) -- 19. Manufacturing Areas 30 200 Y~s7 20. Mechanical Equipment Room 30 300 r--;\) 21. Nurseries for Children (Day care) 7 35 Yes 22. Offices .10 100 Yes' I 23. School Shops and Vocational j Rooms 50 50 Yes 24. Skating Rinks 50 SOon Yes~ I the , , skating area; 15 on the deck 25. Storage and Stock Rooms 30 I 300 "0 I 26. Stores-Retail Sales Rooms Basement " 30 Yes Ground Floor 50 30 Yes Upper Floors 10 60 Yes 27. Swimmmg Pools 50 50 for Yes' the pool area: 15 on [he dl'ck 30 '00 I I 28. Warehouses I :-':0 29. All others 50 100 I I For additional rrovi~ions on number of cxil\ from Group H <Jnù I ()ccuranclc\ and from rooms conl<:iining fucl-fired equipment Of cc!luJo...c nitrale. ....cc Seclinns 3320. 3321 and .1.122, rc\pcctively. lThis table shall no! be used to dctermine working SpJCC rcquircmcnI\ pcr pcr\on. 'Elevators shall nol be con.\lrucd as providing a required exit. 4Acccss (0 secondary .íJrcas on balconies Of mezzanines may be by stair... onJy. except when , such secondary areas contain the only avaiJable roilet faciJities. ~Rcvicwíng st<:inds. grandstands, bleachers, and folding and tclcscopic bleachers need not comply. hAccess requirements for conference rooms, dining rooms, lounges and exhibit reoms that arc parI of an officc use shall be the same as requircd for the office u.l,c. 'Access to flt",rs other than that closest to grade may be by slairs only, except when the only available toilct facilities are on other levels, r.Whcn the floor closest to the grade offers the s<:tme rrogram\ and activitlcs J.vailJ.bk on other floors, access to thc O!hcr floors may be by "'[J.lrs only, except whcn the only available toilet facilities arc on other levcls. 'Acccss to floors othcr than that closest to grade and 10 garages u...cd In connection \\ nh apartment houses may be by stairs only. 'IISce Section 1214 for access to buildings and facilities In hotels and apJ.f!mcnls. II See Section 3303 for basement exit requiremcnts. ~; I~Occupant load based upon five persons for each aIlL!', including 15 fcct of runWJY- 6 Item //3B (5) POSTING OF ROOM CAPACITY MAXIMUM OCCUPANT LOAD 108 STANDING 50 DINING r1 - CLASSROOM, ASSEMBLY AREA OR SIMILAR USE <- SIGN REQUIRED FOR ANY ROOM HA VING AN OCCUPANT LOAD OF 50 OR MORE, WITHOUT FIXED SEATS USC Section 3302(c) UFC Section 25.114(a) 7 Item 113B (6) NUMBER OF EXITS A MINIMUM OF: ONE EXIT FROM ANY USABLE PORTION OF A BUILDING OR ROOM TWO EXITS WHERE REQUIRED BY TABLE NO. 33-A TWO EXITS FROM SECOND STORY WHEN OCCUPANT LOAD > 10 (except individual dwelling units) TWO EXITS FROM THIRD STORY TWO EXITS FROM BASEMENT (except individual dwelling units, service areas, or storage and laundry areas <300 sq. ft.) THREE EXITS FROM EVERY STORY OR PORTION WITH AN OCCUPANT LOAD OF 501 TO 1000 FOUR EXITS FROM EVERY STORY OR PORTION WITH AN OCCUPANT LOAD OF 1001 OR MORE Section 3303(a) 8 Item 113B (7) This exceptidrY ~ermits two ormore~âwe"ing units in a basement to have access to only one exit when the occupant load does not exceed 10. One exit required ~ AI !:, Dwelling Dwelling Dwelling ! - Dwelling - unit unit unit un!! 100r less 10 or less occupants occutJants exit '" exit - ...... exit exit - ...... ¡ ¡ ¡ ¡ - ! ! . ,,' : .---! ¡- - I exit eXit eXit exit Dwelling Dwelling Dwelling Dwe'ilng unit unit unit unit Basement or second story The exception also permits occupants of dwelling units on the second story, and in the basement, to have access to only one exit even though the total occupant load of the floor exceeds 10. NUMBER OF EXITS Section 3303ia), Exception 1 Item //3B (8) One exit required / for third story maximum of 500 ~ square feet and roof not occupied.' Individual dwelling unit . Can use a combination of usable Ihird floor and Occupied rool as long as Ihe lofal area does not exceed 500 square feet (R-3 Occupancy only). EXITS REQUIRED Section 3303 (a), Exception 3 10 Item 113B (9) This provision will apply to the second floor level within an individual dwelling unit no matter what story of the building it is on, provided that only one exit is required by Table No. 33-Ä. r- One . I ·t Third floor Two exits I" ex: < 500 square feet required Individual , from story. dwelling unit i One Second floor , I eXit , " , / I ~ I First floor One . ~ eXit , " " ¡ "' I lOne t I " . I exit Second floor , , Individual I I I dwelling unit I "' One I First floor exit - -. . I Exception 3 is similar to Exception 2 but will apply to the third floor within an individual dwelling unit when it is limited to 500 square feet or less. NUMBER OF EXITS Section 3303 (a), Exceptions 2 and 3 11 Item 113B (0) Given: 400 occupants per floor Exits into first floor ~ Exit enclosures--------- , , 11 2 exits I ~, -- -;....-- 2 exits iJ required I, required !, : _JL 2 exits " " ~-- , , :1 required I, 'I , 600 total occupants ~ ; ¡ " 2 exits I, 3 exits required -~ ~- " , ~ Ii required II - - -. il - -- Enclosure exit Case 1 Case 2 The number of exits should be determined based upon the number of occupants that are exiting from a particular floor. The number of exit enclosures need not be increased due to the number of occupants within the enclosure. EXITS REQUIRED Section 3303 (a) 12 Item 311B (11) ROOM OR AREA -- DIAGONAL ~ 1/2 DIAGÒNAL ~ -- -- -~ -- ---- ~ -- ~ -- - --- -~ -- -~' - ~ --- , -' .... - - ~ ARRANGEMENT OF EXITS Sec. 3303(c) 15 Item 113B (12) - ~_.- - Given: Three or more exits required , Overall diagonal ~ ....... One-half of overall diagonal ,'- - I ~ "~ The location of two of the exits will now be controlled by one-half the overall diagonal distance. The additional exits will only be regulated by the "reasonable" distance, which will be determined by the building official on a case-by-case basis. ARRANGEMENT OF EXITS Section 3303 (c) 16 Item 113B (13) Open stairway I , ~. Open parking garage \ \ \ \ '-------- .. ~ \ ~ I ] \ I \ \ \ 250 feet maximum travel distance The travel distance in an open parking garage only needs to be measured to the exit stairway. This will also apply when the stairway is unenclosed per Section 3309 (a), Exception 3 or when enclosed with glazing per Section 3309 (b). DISTANCE TO EXITS Section 3303 (d) 23 Item 113B (14) EXITS THROUGH ADJOINING ROOMS exit corridor, exit enclosure or egress from the building t .... .- ADJOINING OR INTERVENING ROOM .- . exit corridor, exit enclosure or egress from the building t more than ADJOINING OR .- one exit required INTERVENING ROOM from room .- .... . EXITS REQUIRED Section 3303(e) 24 Item 113B (15) ~)(ITS THROUGH ADJOINING ROOMS exit corridor, exit enclosure or egress from the building t .- exiting not permitted KITCHEN, STORE ROOM, REST ROOM, CLOSET OR SIMILAR SPACE . exit corridor, exit enclosure or egress from the building t - .- ADJOINING OR INTERVENING ROOM FOYER, LOBBY .- OR RECEPTION .- RX)'.1 (constructed as required for corridors) . EXITS REQUIRED Section 3303(e) 25 Item 113B (16) EXITS THROUGH ADJOINING ROOMS exit corridor, exit enclosure t or egress from tht' building I ~.J ~ ..- Occupant Load of 10 or less ADJOINING OR t INTERVENING ROOM t I t . -ÞO t ~ { OCCUPANT LOAD OF } -ÞO EACH ADJACENT ROOM ~ IS 10 OR LESS -ÞO ~ . ADJOINING OR INTERVENING ROOM ... exit corridor, exit enclosure . or egress from the building EXITS REQUIRED Section 3303(e), Exception 2 26 I tern 113B (17) '''- 6'S" MINIMUM ~ HANDRAIL Sec. 3306() -./ 9" l MINIMUM RUN 4" MIN. RISE 8" MAXIMUM RISE OCCUPANT LOAD LESS THAN 10 (Private Stairway) 6'S" MINIMUM MAXMIMUM TREAD RUN HEADROOM . VARIATION OF 3/8 INCH MAXIMUM RISER V ARIA TION HANDRAIL OF 3/8" Sec. 33D6(j) MINIMUM RUN 4" MIN. RISE 7" MAXIMUM RISE OCCUPANT LOAD OF 10 OR MORE STAIRWAYS Sec. 3306 59 Item 113B (18) Sloping Riser height grade Þ 7 inches maximum - , ~. (8 inches maximum / for R-3) . Riser may be less than 4 inches. Bottom - - ~ ~ Sloping grade . - Slope not to exceed 3 inches in 3 feet of stairway width. Top RISE AND RUN Section 3306 (c), Exception 2 60 Item 113B (19) HORIZONTAL EXIT is an exit from one building into another building on approximately the same level, or through or around a waIl constructed as required for a two-hour occupancy separation and which completely divides a floor into two or more separate areas so as to establish an area of refuge affording safety from fIre or smoke coming from the area from which escape is made. A HORIZONTAL EXIT MAY BE CONSIDERED AS A REQUIRED EXIT WHEN CONFORMING TO THE PROVISIONS OF CHAPTER 33 MINIMUM 1 1/2 HOUR FIRE ASSEMBLY þo TWO-HOUR FIRE- AREA B RESISTIVE WALL þo AREA A A HORIZONTAL EXIT SHALL NOT SERVE AS THE ONLY EXIT FROM A PORTION OF A BUILDING· WHEN TWO OR MORE EXITS ARE REQUIRED, NOT MORE T:AN ONE HALF OF THE TOTAL NUMBER OF EXITS OR TOTAL EXIT WIDTH MAY BE . HORIZONTAL EXITS HORIZONTAL EXITS Section 3308 3 Item 113B (20) . "'.-- _~..,... 1· . .'......' .,;..~..... - - . DOOR SWING AREA A AREA B TWO-HOUR FIRE- RESISTIVE WALL Note: If occupant load >50, two doors must swing in direction of exit travel. AREA E AREA C THREE EXITS TWO EXITS REQUIRED REQUIRED ONE EXIT REQUIRED ~ TWO-HOUR FIRE- RESISTIVE WALL HORIZONTAL EXITS Section 3308 4 Item 113B (21) DI~ø.RClE!ÄÆAS Horizontal exit capacity is based on net clear floor area, General: 3 sq. ft./occ. 1-1 ambulatory: 15 sq. ft.locc. 1-1 nonambulatory: 30 sq. ft./occ. A 8 NOTE: Exils for -A" adequate to '/; meet 1he provisions of Chapter 33 ,/', but need not include added capacity /', imposed by occupants entering ;;:; through horizontal exi1 from "8." / E' Horizontal exit Exit ~ _ _- Xlt . Unlike the provisions of exiting through an adjoining room the occupant load which exits through a horizontal exit need not be included when calculating the exit requirements for the room which is receiving the occupants. This benefit is based on the fact that by exiting through the two-hour wall and into a compartment away from the fire or other hazard, occupants would either be able to remain in that area until the hazard has been controlled, or until the orderly use of the remaining exits is possible. HORIZONTAL EXITS Section 3308 5 Item //3B (22) EVERY INTERIOR STAIRWAY, RAMP OR ESCALATOR SHALL BE ,ENCLOSED AS SPECIFIED IN SECTION 3309. .» \\ EXCEPT: . In other than Group H and I Occupancies, an enclosure need not provided for a stairway, ramp or escalator serving only one adjacent floor and not connected with corridors or stairways serving other floors. . Stairs In R-3 Occupancies and stairs within individual dwelling units of R-1 Occupancies need not be enclosed. . Stairs in open parking garages ST AIRWAYS ENCLOSURES Section 3309(a) 6 Item 113B (23) .>~, . _. < . ". : r:::"". "_' ~ ,. -'~. \' , ç-" .- '. "' --- ~-MEeHANLCAL :VENTlLA TION_' IN A SMOKEPROOF ENCLOSURE WITH MECHANICAL VENTILATION, THE FOLLOWING REQUIREMENTS MUST BE ADDRESSED: · Doors · Vestibule size · Vestibule ventilation · Smoke trap · Stair shaft air movement system · Operation of ventilating equipment · Standby power · Acceptance testing · Emergency lighting 44"MIN. 6"MAX CEILING EXHAUST z SMOKE l DUCT '" TRAP b 20NE N ~MUSTNOT8E BELOW SMOKETRAP 6" MAX, SUPPLY DUCT. :%' CROSS SECTION OF VESTIBULE SMOKEPROOFENCLOSURE Section 3310(9) 17 Item 113B (24) EXIT COURT is a yard or court providing access to a public way for one or more required exits. r'-~ Une I , Exit Court Exit Court t: I " Exit Court I ~I I EXIT PASSAGewAY EXIT COURT EXIT PASSAGewAY EXIT CO U RTS Section 3311 18 -.-., Item 113B (25) A1SlJ;ScSHALl TERMI~ATEJN A: ." H ;; CROSS AISLE - · FOYER · EXIT EXIT --LOBBY EXIT 00000000 00000000 DO DO Do 00--- - 0 DODD Do 0 00000000 00000000 00000000 EJEJoEJEJEJEJEJ CROSS AISLE 00000 EJoooEJ EJEJEJEJEJ EJEJEJEJEJ EJEJEJEJEJ EJEJEJEJEJ EJEJEJEJEJ EJEJoEJEJ EJEJEJEJEJ EJEJEJEJEJ EJEJEJEJEJ EJEJEJEJEJ _ IN GROUPS A AND E OCCUPANCIES, AISLES SHALL NOT HAVE A DEAD END GREATER THAN 20 FEET IN LENGTH CROSS AISLES Section 3315(e) 31 Item 113B (26) BASIC WIDTH OF AISLES IN AREAS HAVING FIXED SEATS FOYER EXIT LEXI~ ,EX/~ y~ V, a: UJ >- 0 LI.. 0 I- -' UJ > AISLE WIDTH AISLE WIDTH <: a: 36" BASIC 42" BASIC l- e +30" TRAVEL +30" TRAVEL 0 UJ 0 ,.... -' 66" TOTAL 72" TOTAL (/) 0 ;¡ N UJ 100/5 = 20 -J !!1 66" 72" 20 x 1.5" = 30" 72" <: (/) (/) 0 a: u 0 I- -J UJ > <: a: l- e 0 ,.... CROSS AISLEl ( EXIT 8'..9" EXIT ~ . 72" + .5(66") = 105" = 8'-9" I I 1 OPTIONAL METHOD OF CALCULATING CROSS AISLE STAGE [72" + .5(66) + .5(66) + .5(72)]/2 = [174"]/2 = 67" OR 7' 3" TOTAL AISLE WIDTH IS DIVIDED BY 2 SINCE EXITS ARE PROVIDED AT EACH END OF CROSS AISLE AND WE ASSUME ONE.HALF OF THE OCCUPANTS GO EACH WAY. AISLES Section 3315 32