Measures for Fire Safety in High Buildings: (To Form Part of Supplement No. 3 to the National Building Code of Canada)

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MEASURES FOR FIRE SAFETY

IN HIGH BUILDINGS

( T O FORM PART OF SUPPLEMENT NO. 3

TO THE NATIONAL ~ U I L D I N G CODE OF CANADA I

ISSUED BY THE ASSOCIATE COMMITTEE

ON THE NATIONAL BUILDING CODE NATIONAL RESEARCH COUNCIL

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S P E C I A L NOTE

ÿ he m e a s u r e s contained in t h i s Supplement have b e e n p r e p a r e d to a i d t h o s e who m u s t develop s o l u t i o n s t o the p r o b l e m of c o n t r o l l i n g s m o k e m o v e m e n t i n buildings in a c c o r d a n c e with t h e r e q u i r e m e n t s of t h e N a t i o n a l

Building Code. T h e knowledge r e q u i r e m e n t s a r e w e l l within t h e c a p a b i l i t i e s of the c o m p e t e n t d e s i g n e r . T h e d e s i g n e r should a p p r e c i a t e , h o w e v e r , t h a t the s u c c e s s f u l application of t h e s e m e a s u r e s c o n s t i t u t e s a d e s i g n p r o b l e m r e q u i r i n g a c l e a r u n d e r s t a n d i n g of t h e p r i n c i p l e s t h a t g o v e r n s m o k e m o v e -

m e n t , a s w e l l a s a n a w a r e n e s s of t h e a s s u m p t i o n s o n which t h e m e a s u r e s a r e based. T h e a s s u m p t i o n s r e g a r d i n g building c h a r a c t e r i s t i c s a s s o c i a t e d with e a c h m e a s u r e a r e included i n t h e text. If t h e building u n d e r c o n s i d e r a - tion h a s c h a r a c t e r i s t i c s t h a t a r e s i g n i f i c a n t l y d i f f e r e n t f r o m t h e s e , a p p r o p r i a t e a d j u s t m e n t s m u s t be m a d e in t h e design. T h i s i s p a r t i c u l a r l y t r u e of m e t h o d s e m p l o y i n g a i r - h a n d l i n g s y s t e m s w h e r e , f o r e x a m p l e , a r e a l i s t i c a s s e s s m e n t of t h e l e a k a g e c h a r a c - t e r i s t i c s of t h e e n c l o s u r e s of s p a c e s into which a i r i s i n t r o d u c e d m a y be c r i t i c a l . In t h i s context, s p e c i a l a t t e n t i o n i s d r a w n t o t h e building p r e s s u r i z a -

tion a p p r o a c h u s e d in conjunction with a s m o k e shaft. T h e r e c o , m m e n d a t i o n s

contained in t h e Supplement f o r t h i s a p p r o a c h w e r e d e v e l o p e d a s s u m i n g a

building with f a i r l y u n i f o r m l e a k a g e c h a r a c t e r i s t i c s. W h e r e a building d e p a r t s s u b s t a n t i a l l y f r o m t h i s m o d e l , t h e d e s i g n m u s t b e a d j u s t e d to c o m p e n s a t e .

An e x a m p l e of t h e l a t t e r condition would b e a building which c o n t a i n s a t t h e l o w e r l e v e l s a l a r g e shopping c o m p l e x of m u c h g r e a t e r f l o o r a r e a than a t t h e h i g h e r l e v e l s . D e t a i l s of t h e a s s o c i a t e d p r o b l e m s a r e given i n a p a p e r which i s b e i n g p r e p a r e d by the Division of Building R e s e a r c h of t h e National R e s e a r c h Council.

T h e d e s i g n e r i s c a u t i o n e d t h a t t h e t a b u l a r a n d g r a p h i c a l i n f o r m a t i o n i n t h i s Supplement have b e e n developed f o r buildings having t h e c h a r a c t e r i s t i c s l i s t e d i n t h i s r e p o r t . It w i l l b e f o r h i m t o j u d g e

the e x t e n t t o which t h e building u n d e r c o n s i d e r a t i o n h a s c h a r a c t e r i s t i c s t h a t w i l l a l l o w t h e a p p l i c a t i o n of t h i s i n f o r m a t i o n . T h i s i s p a r t i c u l a r l y i m p o r t a n t w h e r e a d e s i g n e r i n t e n d s t o develop h i s own s m o k e c o n t r o l a p p r o a c h . In s o m e c a s e s t h e d e s i g n m a y p r o v e sufficiently c o m p l e x t o n e c e s s i t a t e t h e u s e of a c o m p u t e r , a n d r e f e r e n c e should b e m a d e to a p a p e r d e s c r i b i n g a c o m p u t e r a p p r o a c h t o t h i s p r o b l e m which is a v a i l a b l e f r o m t h e D i v i s i o n of Building Re s e a r c h .

F i n a l l y , i t should be noted t h a t t h e N a t i o n a l Building Code r e q u i r e s t h a t a c h e c k be m a d e of t h e s m o k e c o n t r o l s y s t e m when r e q u e s t e d by the a u t h o r i t y h a v i n g j u r i s d i c t i o n i n a c c o r d a n c e with t h e p r o c e d u r e s d e s c r i b e d i n Appendix C of t h i s Supplement. T h i s w i l l i n d i c a t e d e f i c i e n c i e s c a u s e d by i n e x a c t e s t i m a t e s of t h e l e a k a g e c h a r a c t e r i s t i c s o r of a i r supply r e q u i r e m e n t s , a n d in a l l but t h e m o s t e x t r e m e c a s e s w i l l p r o v i d e a n opportunity f o r a p p r o p r i a t e a d j u s t m e n t s b e f o r e t h e s y s t e m i s put into s e r v i c e . Copyright © NRC 1941 - 2019 World Rights Reserved © CNRC 1941-2019 Droits réservés pour tous pays

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CONTENTS Introduction P a g e 2 C h a p t e r 1 C h a p t e r 2 S e c t i o n 2 ( a ) S e c t i o n 2 ( b ) S e c t i o n 2 ( c ) S e c t i o n 2 ( d ) S e c t i o n 2 ( e ) S e c t i o n 2 ( f ) S e c t i o n 2 ( g ) S e c t i o n 2 ( h ) S e c t i o n 2 ( i ) S e c t i o n 2 ( j ) C h a p t e r 3 Appendix A Appendix B Appendix C Scope of M e a s u r e s 3

M e a s u r e s f o r L i f e Safety i n High Buildings 22

M e a s u r e A

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F u l l y S p r i n k l e r e d Buildings 22 M e a s u r e s B and C

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O p e n C o r r i d o r A c c e s s t o S t a i r s and E l e v a t o r s 25 M e a s u r e s D and E

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P r o t e c t e d V e s t i b u l e A c c e s s t o S t a i r s and E l e v a t o r Shafts 3 2 M e a s u r e s F and G

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P r e s s u r i z e d S t a i r and E l e v a t o r Shafts 4 3 M e a s u r e H

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F u l l y P r e s s u r i z e d Buildings 52 M e a s u r e s I and J

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Building C o r e P r e s s u r i z e d M e a s u r e K

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V e r t i c a l l y Divided Building 63 M e a s u r e L

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A . r e a s of Refuge 69 M e a s u r e M

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R e s i d e n t i a l Buildings with 7 5 B a l c o n i e s

M e a s u r e I?!

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Connected Buildings 7 8

Venting of F l o o r A r e a s 80 G r a p h s t o b e u s e d in Applying Smoke C o n t r o l M e a s u r e s 85 A s s u m p t i o n s Used in Developing F i r e Safety M e a s u r e s 10 2 C h e c k of a Smoke C o n t r o l S y s t e m 12 2 B i b l i o g r a p h y Copyright © NRC 1941 - 2019 World Rights Reserved © CNRC 1941-2019 Droits réservés pour tous pays

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INTRODUCTION

E x p e r i e n c e with high buildings h a s shown that t h e t i m e r e q u i r e d f o r c o m p l e t e evacuation c a n exceed t h a t which i s c o n s i d e r e d n e c e s s a r y f o r t h e s a f e e g r e s s of a l l o c c u p a n t s . Studies of the 'chimney e f f e c t ' and

o b s e r v a t i o n s of s m o k e movement in f i r e s have shown that p r e s e n t m e a s u r e s f o r containing a f i r e on a lower s t o r e y will not u s u a l l y p r e v e n t t h e m o v e m e n t of s m o k e t h r o u g h e l e v a t o r , s t a i r and o t h e r v e r t i c a l s h a f t s t o t h e u p p e r

s t o r e y s of a high building. Occupants of high buildings, and p a r t i c u l a r l y t h o s e o n upper s t o r e y s , m a y be f a c e d with s e v e r e s m o k e conditions f r o m f i r e s o c c u r r i n g in s t o r e y s below t h e m , b e f o r e t h e i r own evacuation i s p o s s i b l e .

T h e m e a s u r e s d e s c r i b e d i n t h i s document a r e designed a s a m e a n s of i m p l e m e n t i n g t h e r e q u i r e m e n t s of NBC Subsection 3 . 2 . 6 . , and a r e intended t o m a i n t a i n s a f e conditions f o r o c c u p a n t s of a high building who m a y h a v e t o

r e m a i n i n t h e building d u r i n g a f i r e , to p r o t e c t exit r o u t e s and to a s s i s t f i r e f i g h t e r s by providing efficient a c c e s s t o the f i r e f l o o r .

T h e s p e c i f i c r e f e r e n c e to Code c l a u s e s i n t h i s document apply t o t h e 1970 edition of t h e National Building Code a s r e v i s e d by Change S e r i e s No. 3 i s s u e d O c t o b e r 1973. Copyright © NRC 1941 - 2019 World Rights Reserved © CNRC 1941-2019 Droits réservés pour tous pays

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CHAPTER

I SCOPE O F MEASURES

This document includes a n u m b e r of detailed m e a s u r e s t h a t m a y b e i n c o r p o r a t e d i n a building in o r d e r to comply with the r e q u i r e m e n t s r e l a t i n g to c o n t r o l of s m o k e that a r e included in Subsection 3 , 2 . 6 . of t h e National Building Code. It is not t h e intention to exclude o t h e r m e a n s of attaining the s a m e o b j e c t i v e s . W h e r e s m o k e c o n t r o l methods o t h e r t h a n t h o s e d e s c r i b e d i n t h i s document a r e developed, they m a y be b a s e d o n t h e

information in Appendix B, Mechanisms of Smoke Movement i n Buildings.

Smoke c o n t r o l m e a s u r e s r e q u i r e d by NBC Subsection 3 . 2 . 6 . v a r y depending on t h e height and occupancy of a building. In a s p r i n k l e r e d building, the r e q u i r e m e n t s f o r c o n t r o l of s m o k e movement a r e m i n i m a l

( s e e M e a s u r e A in Chapter 2 ) . In v e r y t a l l buildings, l i m i t s a r e placed on p e n e t r a t i o n of s m o k e into exit s t a i r s , f i r e f i g h t e r s ' elevator and a l l f l o o r a r e a s o t h e r t h a n t h e one on which f i r e o c c u r s . This i s achieved by M e a s u r e s

B, D, F, H and I in Chapter 2 . In c e r t a i n buildings of l e s s e r height and

l i m i t e d population, exit s t a i r s and f i r e f i g h t e r s ' e l e v a t o r s a r e p r o t e c t e d , and s m o k e m a y b e expected t o e n t e r upper f l o o r a r e a s . T h i s a p p l i e s w h e r e M e a s u r e s , C , E , G and J , d e s c r i b e d i n Chapter 2, a r e employed. In o t h e r buildings, t h e s p r e a d of smoke into shafts and floor a r e a s i s a c c e p t e d , but a r e a s of refuge a r e provided that a r e maintained s m o k e f r e e , can be reached by a l l people in t h e building within a few m i n u t e s and a r e linked t o o u t d o o r s by s a f e m e a n s of e g r e s s . They a r e d e s c r i b e d i n M e a s u r e s K and L in C h a p t e r 2 .

W h e r e M e a s u r e s A, B , D, F , H and I i n C h a p t e r 2 a r e applied, i t i s a s s u m e d t h a t i n t h e event of f i r e occupants of t h e f l o o r on which t h e f i r e o c c u r s will l e a v e by exit s t a i r s i m m e d i a t e l y following t h e sounding of a f i r e a l a r m , and that o c c u p a n t s of the floor i m m e d i a t e l y above t h e f l o o r o n which t h e f i r e o c c u r s will be advised to l e a v e by t h e f i r s t a r r i v i n g f i r e d e p a r t m e n t

o f f i c e r o r o t h e r p e r s o n assigned t h i s r e s p o n s i b i l i t y . Occupants of a l l o t h e r f l o o r s m a y r e m a i n on t h e i r f l o o r s u n l e s s o t h e r w i s e d i r e c t e d .

W h e r e M e a s u r e s C,

E ,

G and J i n C h a p t e r 2 a r e a p p l i e d , i t is a s s u m e d that occupants of a l l f l o o r s will move i m m e d i a t e l y into t h e s t a i r - s h a f t s , and will t h e n p r o c e e d slowly to the o u t d o o r s following t h e sounding of a g e n e r a l f i r e a l a r m .

W h e r e M e a s u r e K in C h a p t e r 2 i s applied ( i . e . , the building i s divided v e r t i c a l l y into two z o n e s ) , i t i s a s s u m e d that occupants of t h e f l o o r o n which the f i r e o r i g i n a t e s will leave by exit s t a i r s , and t h a t t h e occupants of a l l o t h e r f l o o r s in t h e zone i n which the f i r e i s d i s c o v e r e d will move t h r o u g h vestibules o r b r i d g e s to floor a r e a s on the s a m e l e v e l in t h e f i r e f r e e s m o k e

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c o n t r o l r e g i o n i m m e d i a t e l y following t h e sounding of a f i r e a l a r m . 0 c c u p a n t s m a y r e m a i n in t h e s e a r e a s of r e f u g e u n t i l f u r t h e r d i r e c t e d b y t h e f i r e

d e p a r t m e n t o f f i c e r .

W h e r e M e a s u r e L in C h a p t e r 2 i s a p p l i e d , i t i s a s s u m e d t h a t o c c u p a n t s of t h e f l o o r o n which t h e f i r e o r i g i n a t e s w i l l l e a v e by exit s t a i r s , and t h a t o c c u p a n t s of a l l o t h e r f l o o r s will move by c o r r i d o r s o r s t a i r s t o a r e a s of r e f u g e t h a t a r e d i s t r i b u t e d throughout t h e building i m m e d i a t e l y following t h e sounding of t h e f i r e a l a r m . O c c u p a n t s m a y r e m a i n in t h e s e a r e a s of r e f u g e until o t h e r w i s e d i r e c t e d . I n a r e s i d e n t i a l building w h e r e r e l i a n c e i s p l a c e d on b a l c o n i e s a s p l a c e s of r e f u g e f r o m s m o k e , a s d e s c r i b e d i n M e a s u r e M in C h a p t e r 2 o c c u p a n t s m a y r e m a i n i n t h e i r s u i t e s when a g e n e r a l f i r e a l a r m i s g i v e n , but should b e p r e p a r e d t o m o v e on t o t h e i r b a l c o n i e s if conditions in t h e s u i t e should b e c o m e u n t e n a b l e .

I t i s a s s u m e d t h a t t h e population of below g r a d e s t o r e y s w i l l not e x c e e d t h e 300 p e r s o n s p e r unit exit width r e f e r r e d t o in NBC A r t i c l e

3 . 2 . 6 . 1 .

,

and t h a t o c c u p a n t s of below g r a d e s t o r e y s w i l l e v a c u a t e t h e building by t h e s t a i r s h a f t s i m m e d i a t e l y a f t e r t h e d i s c o v e r y of a f i r e in a below g r a d e s t o r e y .

I t i s a l s o i m p o r t a n t t h a t f i r e f i g h t e r s a r e p r o v i d e d with a s m o k e f r e e a c c e s s t o below g r a d e f i r e f l o o r s . T h e M e a s u r e s d e s c r i b e d a s A, B ,

C , D , E, F, G , L and M include p r o v i s i o n s designed to s e p a r a t e the exit

s t a i r s s e r v i n g a b o v e g r a d e s t o r e y s f r o m t h o s e s e r v i n g below g r a d e s t o r e y s , and to l i m i t e n t r y of s m o k e into t h e s e s h a f t s . It i s a l s o r e q u i r e d that e l e v a t o r and s e r v i c e s h a f t s be p r o v i d e d with a s e p a r a t i o n n e a r g r a d e , o r b e d e s i g n e d t o l i m i t t h e i r functioning a s p a t h s of s m o k e m o v e m e n t into u p p e r f l o o r

a r e a s . I n M e a s u r e s H, I and J no s p e c i a l p r e c a u t i o n s a r e n e c e s s a r y t o p r o t e c t s h a f t s i n below g r a d e s t o r e y s b e c a u s e t h e s y s t e m of p r e s s u r i z a t i o n p l u s venting of t h e f i r e f l o o r p r o t e c t s a l l s h a f t s , w h e t h e r o r not t h e s e

p e n e t r a t e below g r a d e s t o r e y s . In M e a s u r e K t h e s e p a r a t i o n into two zones is m a i n t a i n e d i n below g r a d e s t o r e y s . S m o k e f r e e a c c e s s will thus b e a v a i l a b l e t o any f l o o r on which f i r e o c c u r s . Copyright © NRC 1941 - 2019 World Rights Reserved © CNRC 1941-2019 Droits réservés pour tous pays

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SYNOPSIS O F MEASURES FOR L I F E

SAFETY I N HIGH BUILDINGS

E a c h of the m e a s u r e s i s i l l u s t r a t e d by a s k e t c h with notes d e s c r i b i n g t h e a p p l i c a b l e conditions ( F i g . 1 t o 18). T h e s e s k e t c h e s a r e intended a s a guide to t h e d e t a i l e d r e q u i r e m e n t s and a s a n a i d t o finding t h e r e l a t i v e c l a u s e s , but they a r e not intended t o l i m i t i n any way the

s c o p e of t h e d e t a i l e d p r o v i s i o n s which i n g e n e r a l p r o v i d e a w i d e r r a n g e of choice t h a n c a n be shown in t h e s k e t c h e s and n o t e s . A s u m m a r y of

r e q u i r e m e n t s a p p l i c a b l e to a l l buildings r e g a r d l e s s of t h e m e a s u r e being u s e d i s given in t h e following p a r a g r a p h .

R e q u i r e m e n t s C o m m o n to a l l M e a s u r e s f o r L i f e Safety i n High Buildings

E l e v a t o r s c o n t r o l l e d by keyed s w i t c h (NBC A r t i c l e 3 . 2 . 6 . 3 ) F i r e f i g h t e r s

'

e l e v a t o r r e q u i r e d (NBC A r t i c l e 3 . 2 . 6 . 4 ) M e a n s of venting e a c h f l o o r a r e a to o u t d o o r s by s m o k e s h a f t windows o r building e x h a u s t s y s t e m (NBC A r t i c l e 3 . 2 . 6. 5) C e r t a i n f l o o r a r e a s i n t h e building a r e s p r i n k l e r e d (NBC A r t i c l e s 3 . 2 . 2 . 8 . and 3 . 2 . 6 . 6 ) L i m i t s o n f l a m e s p r e a d and s m o k e p r o d u c t i o n r a t i n g s f o r i n t e r i o r f i n i s h m a t e r i a l s in c e r t a i n locations (NBC A r t i c l e 3 . 2 . 6 . 7 ) C e n t r a l a l a r m and c o n t r o l f a c i l i t y r e q u i r e d (NBC A r t i c l e 3 . 2 . 6 . 8 ) Voice c o m m u n i c a t i o n s y s t e m r e q u i r e d if building i s o v e r 120 f t . high

(NBC A.rticle 3 . 2. 6. 9 ) F i r e p r o t e c t i o n r e q u i r e d f o r e l e c t r i c a l f e e d e r s t o e m e r g e n c y equipment (NBC A r t i c l e 3 . 2 . 6.10) P o w e r to o p e r a t e e m e r g e n c y lighting a l a r m and c o m m u n i c a t i o n s s y s t e m s (NBC A r t i c l e 3. 2 . 6.11) E m e r g e n c y p o w e r t o o p e r a t e e l e v a t o r s r e q u i r e d if building i s o v e r 120 f t . high (NBC A r t i c l e 3 . 2 . 6.11) Copyright © NRC 1941 - 2019 World Rights Reserved © CNRC 1941-2019 Droits réservés pour tous pays

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M E A S U R E A. F U L L Y S P R I N K L E R E D B U I L D I N G

1. Door to outdoors i n each stairshaft held open during a fire emergency (2A(2)) *

Stairshaft serving floors below the lowest e x i t level

i s separate from stairshaft serving floors above that storey (2A (3))

Stairshaft serving floors below the lowest e x i t level

i s pressurized during a fire emergency (2A(3))

2. Elevator shaft terminates not lower than the first floor below the lowest e x i t storey or has vestibules at each elevator door i n lower storeys (2A(5))

3 . V e r t i c a l service spaces provided w i t h firestops at the first floor below the lowest e x i t storey or are vented to outdoors at top (2A(6))

A i r moving fans are stopped i n a system that serves more than two storeys (NBC Sentence 3.2.6.2. (6))

F i g u r e 1 T y p i c a l F l o o r P l a n , M e a s u r e A

* First number, 2, indicates Chapter 2. Letter "A"

indicates Measure A i n 'Chapter 2. Last number, (2), indicates numbered sentence i n Measure A .

M e a s u r e A s a t i s f i e s N B C s e n t e n c e 3. 2.6. 2 ( 6 ) f o r g r o u p s A,C, D , E , o r F, M a j o r

O c c u p a n c y C l a s s i f i c a t i o n

N o l i m i t o n h e i g h t

A l l f l o o r a r e a s s p r i n k l e r e d . ( N B C s e n t e n c e 3. 2 . 6 .

2

( 6 ) )

L i m i t s o n f l a m e s p r e a d a n d s m o k e d e s c r i b e d

i n N B C a r t i c l e 3. 2 . 6 . 7 a r e r e l a x e d .

(11)

M E A S U R E B. OPEN C O R R I D O R A C C E S S TO S T A I R S A N D ELEVATORS i n c l u d i n g r e s t r i c t i o n s o n m o v e m e n t o f s m o k e f r o m f l o o r t o f l o o r

F i g u r e 2 T y p i c a l F l o o r P l a n , M e a s u r e B

1. Stainhaft serving floors below the lowest e x i t level is separate from stainhaft serving floors above that storey _(2B(3))

Stainhaft serving floors below the lowest e x i t level is pressurized during a fire emergency (2B(3))

2. Elevator shaft terminates not lower than the first floor below the lowest e x i t storey or has vestibules at each elevator door i n lower storeys (2B(4))

3 . Vertical service spaces provided with firestops a t the first floor below the lowest e x i t storey and a t intervals not exceeding five storeys or are vented to outdoors at top _(2B(5))

4 . O p e n corridor or balcony providing access to stairs and firefighters' elevator (2B(2))

Elevator shaft and stairshaft unheated

A i r moving fans are stopped i n a system that serves more than two storeys (2B(7))

Certain dampers close i n air handling ducts during a fire emergency (2B(8)) M e a s u r e B s a t i s f i e s N B C s e n t e n c e s 3. 2 . 6 . 2 ( 2 )

( 3 )

a n d ( 4 ) f o r a n y M a j o r O c c u p a n c y C l a s s i f i c a t i o n N o l i m i t o n h e i g h t Copyright © NRC 1941 - 2019 World Rights Reserved © CNRC 1941-2019 Droits réservés pour tous pays

(12)

M E A S U R E C. O P E N C O R R I D O R A C C E S S TO S T A I R S A N D E L E V A T O R S n o a d d i t i o n a l r e s t r i c t i o n s o n m o v e m e n t o f s m o k e f r o m f l o o r t o f l o o r

1

.

Stairshaft serving floors below the lowest e x i t l e v e l is separate from stairshaft serving floors above that storey _(2C(3))

Stairshaft serving floors below the lowest e x i t l e v e l is pressurized during a fire emergency (2C(3))

2. Elevator shaft terminates not lower than the first floor below the lowest e x i t storey or has vestibules at each elevator door i n lower storeys (2C(4))

3 . O p e n corridor or balcony providing access to stairs and firefighters1 elevator (2C (2))

Elevator shaft and stairshaft unheated

A i r moving fans are stopped i n a system that serves more than two storeys (2C(5) F i g u r e 3 T y p i c a l F l o o r P l a n , M e a s u r e C M e a s u r e C s a t i s f i e s N B C s e n t e n c e 3. 2.6. 2 ( 7 ) f o r g r o u p s A, C, D, E , o r F, M a j o r O c c u p a n c y C l a s s i f i c a t i o n L i m i t o n p o p u l a t i o n ( N B C s e n t e n c e 3. 2. 6. 2 ( 7 ) ) L i m i t e d t o b u i l d i n g s n o t m o r e t h a n 250 f t . h i g h ( N B C s e n t e n c e 3. 2. 6. 2.

(7))

(13)

M E A S U R E D. P R O T E C T E D V E S T 1 B U L E A C C E S S TO S T A I R S A N D E L E V A T O R S i n c l u d i n g r e s t r i c t i o n s o n m o v e m e n t o f s m o k e f r o m f l o o r t o f l o o r

1

.

Door to outdoors i n each stairshaft held open during a fire emergency (2D(7))

Stairshaft serving floors below the lowest e x i t level is separate from stairshaft serving floors above that level (2D(8))

Stairshaft serving floors below the lowest e x i t level is pressurized during a fire emergency _(2D(8))

2. Elevator shaft terminates not lower than the first floor below the lowest e x i t storey or has vestibules at each elevator door i n lower storeys (2D(13))

3. Firefighters'elevator shaft provided w i t h vent to outdoors at top and bottom during a fire emergency _(2D(9))

4 . V e r t i c a l service spaces provided w i t h firestops a t the first floor below the lowest e x i t storey and a t intervals not

exceeding five storeys or are vented to outdoors at top (2D(12))

5 . Vestibule vented to outdoors during a fire emergency or pressurized (2D(5))

Vents to vestibules openable from central control f a c i l i t y i f building is over 120 f t high (2D(6))

A i r moving fans are stopped i n a system that serves more than two storeys (2D(15))

Certain dampers close i n air handling ducts during a fire emergency (2D(16)) F i g u r e 4 T y p i c a l F l o o r P l a n , M e a s u r e D M e a s u r e D s a t i s f i e s N B C s e n t e n c e s 2. 3. 6.

2 (21, (31,

a n d ( 4 ) f o r a n y M a j o r O c c u p a n c y C l a s s i f i c a t i o n N o l i m i t o n h e i g h t Copyright © NRC 1941 - 2019 World Rights Reserved © CNRC 1941-2019 Droits réservés pour tous pays

(14)

M E A S U R E E. P R O T E C T E D V E S T I B U L E A C C E S S TO S T A I R S A N D E L E V A T O R S

n o a d d i t i o n a l r e s t r i c t i o n s o n m o v e m e n t o f s m o k e f r o m f l o o r t o f l o o r

1

.

Door to outdoors i n each stairshaft held open during a fire emergency (2E(6))

Stairshaft serving floors below the lowest exit level

i s separate from stairshaft serving floors above that level (2E(7))

Stairshaft serving floors below the lowest exit level

i s pressurized during a fire emergency (2E(7))

2. Elevator shaft terminates not lower than the first floor below the lowest e x i t storey or has vestibules at each elevator door i n lower storeys _{( 2 E ( l l ) )}

No special protection against smoke for elevator shafts or vertical service spaces other than firefighters elevator

3 . Firefighters elevator shaft provided w i t h vent to outdoors at top and bottom during a fire emergency (2E(8))

4. Vestibule vented to outdoors during a fire emergency or pressurized (2E(4))

Vents to vestibules openable from central control f a c i l i t y i f building is over 1 2 0 f t high _(2E(5))

A i r moving fans are stopped i n a system that serves more than two storeys (2E(12))

F i g u r e 5 T y p i c a l F l o o r P l a n , M e a s u r e E

M e a s u r e E s a t i s f i e s N B C s e n t e n c e

3.

2 . 6 . 2 ( 7 ) f o r g r o u p s A , C, D, E , o r

F,

M a j o r

O c c u p a n c y C l a s s i f i c a t i o n

L i m i t o n p o p u l a t i o n ( N B C s e n t e n c e

3.

2. 6. 2 (71)

L i m i t e d t o b u i l d i n g s n o t m o r e t h a n 2 5 0 f t . h i g h ( N B C s e n - t e n c e

3.

2. 6. 2 ( 7 ) )

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M E A S U R E F. P R E S S U R I Z E D S T A I R A N D E L E V A T O R S H A F T S

i n c l u d i n g r e s t r i c t i o n o n m o v e m e n t o f s m o k e f r o m f l o o r t o f l o o r

1

.

Door to outdoors i n each stairshaft held open during a fire emergency (2F(2))

Stairshaft pressurized during a fire emergency (2F(2))

Stairshaft serving floors below the lowest e x i t level is separate from stairshaft serving floors above that level (2F(3))

Stairshaft serving floors below the lowest e x i t level is pressurized during a fire emergency (2F(3))

2. Firefighters elevator shaft pressurized during a fire emergency (2F(4))

3 . Elevator shafts other than firefighters ' elevator vented to outdoors a t top (2F(8))

4 . V e r t i c a l service spaces provided with firestops a t the first floor below the lowest e x i t storey and at intervals not exceeding five storeys or are vented to outdoors a t t o p (2F(7))

A i r moving fans are stopped i n a system that serves more than two storeys during a fire emergency ( 2 F ( l l ) )

Certain dampers i n air handling ducts close during a fire emergency (2F(12)) F i g u r e 6 T y p i c a l F l o o r P l a n , M e a s u r e F M e a s u r e F s a t i s f i e s N B C s e n t e n c e s 3. 2.6. 2 (21, (31, a n d ( 4 ) f o r a n y M a j o r O c c u p a n c y C l a s s i f i c a t i o n N o l i m i t o n h e i g h t Copyright © NRC 1941 - 2019 World Rights Reserved © CNRC 1941-2019 Droits réservés pour tous pays

(16)

M E A S U R E G. P R E S S U R I Z E D S T A I R A N D E L E V A T O R S H A F T S

n o a d d i t i o n a l r e s t r i c t i o n o n m o v e m e n t o f s m o k e f r o m f l o o r t o f l o o r

1 . Door to outdoors i n each stairshaft h e l d open during a fire emergency (2G(2))

Stairshaft pressurized during a fire emergency (2G (2))

Stairshaft serving floors below the lowest e x i t level is separate from stairshaft serving floors above that l e v e l (2G(3))

Stairshaft serving floors below the lowest e x i t l e v e l is pressurized during a fire emergency

(2G (3))

2. Firefighters' elevator shaft pressurized during a fire emergency (2G (4))

3 . N o special protection against smoke for elevator shafts or v e r t i c a l service spaces other than firefighters' elevator

A i r moving fans are stopped i n a system that serves more than two storeys during a f i r e emergency (2G (7)) F i g u r e 7 T y p i c a l F l o o r P l a n , M e a s u r e G M e a s u r e G s a t i s f i e s N B C s e n t e n c e 3. 2. 6. 2. ( 7 ) f o r g r o u p s A , C , D, E o r F, M a j o r O c c u p a n c y C l a s s i f i c a t i o n L i m i t o n p o p u l a t i o n ( N B C s e n t e n c e 3. 2 . 6 . 2 ( 7 ) ) L i m i t e d t o b u i l d i n g s n o t m o r e t h a n 2 5 0 f t . h i g h ( N B C s e n t e n c e 3. 2. 6. 2 ( 7 ) ) Copyright © NRC 1941 - 2019 World Rights Reserved © CNRC 1941-2019 Droits réservés pour tous pays

(17)

-

1 3

-

M E A S U R E H. B U I L D I N G F U L L Y P R E S S U R I Z E D

F i g u r e 8 T y p i c a l F l o o r P l a n , M e a s u r e H

1

.

A l l floor areas pressurized (2H(2))

Provision for modulating air supply for building pressurization during warm weather _(2H₍₃₎₎ 2. Fire floor provided with means of venting to

outdoors by smokeshaft or windows _{(2H (6))} 3. A proportion o f air for building pressurization

directed into stairshafts (2H (2))

Doors to outdoors i n stairshafts not held open during a fire emergency (2H(4))

4 . Except as required for venting a l l openings i n perimeter walls and roof are kept closed during a fire emergency (2H(4))

Except as required for pressurization, air moving fans are stopped i n a system that serves more than two storeys during a fire emergency (2H(3)) Certain dampers i n air handling ducts are closed 4 during a fire emergency (2H(5))

M e a s u r e H s a t i s f i e s N B C s e n t e n c e s 3.

2 . 6 . 2 ( 2 1 ,

( 3 1 ,

a n d ( 4 ) f o r a n y M a j o r O c c u p a n c y C l a s s i f i c a t i o n N o

l i m i t o n h e i g h t

(18)

M E A S U R E

I.

B U I L D I N G CORE P R E S S U R I Z E D

i n c l u d i n g r e s t r i c t i o n o n m o v e m e n t o f s m o k e f r o m f l o o r t o f l o o r o u t s i d e c o r e

1

.

Enclosing w a l l o f core i s a fire separation w i t h self closing doors

Central core i s pressurized during a fire emergency (21(2))

A l l openings i n perimeter walls and roof o f core kept closed during a fire emergency (21(3))

2. Fire compartment is vented t o outdoors during a fire emergency by smokeshaft or windows (21(4)) 3. Vertical service spaces outside core provided w i t h

firestops a t the l e v e l o f the first floor below the lowest e x i t storey and at intervals not exceeding f i v e storeys or are vented to outdoors a t the top (21(6))

4. Doors to outdoors i n stairshafts not held open during a fire emergency except as required for pressurizing the core (21(3))

A i r moving fans are stopped i n a system that serves more than two storeys i n a fire emergency

(2 I(7))

Certain dampers i n a i r handling ducts are closed during a fire emergency (21(8))

F i g u r e 9 T y p i c a l F l o o r P l a n , M e a s u r e I M e a s u r e I s a t i s f i e s N B C s e n t e n c e s 3 . 2 . 6 . 2 ( 2 1 , (31, a n d ( 4 ) f o r a n y M a j o r O c c u p a n c y C l a s s i f i c a t i o n N o l i m i t o n h e i g h t Copyright © NRC 1941 - 2019 World Rights Reserved © CNRC 1941-2019 Droits réservés pour tous pays

(19)

M E A S U R E J. B U I L D I N G C O R E P R E S S U R I Z E D

n o a d d i t i o n a l r e s t r i c t i o n o n m o v e m e n t o f s m o k e f r o m f l o o r t o f l o o r o u t s i d e c o r e

F i g u r e 1 0 T y p i c a l F l o o r ~ l a n , M e a s u r e J

1

.

Enclosing w a l l o f core is a fire separation w i t h self closing doors

Central core is pressurized during a fire emergency (2J(2))

A l l openings i n perimeter walls and roof o f core are kept closed during a fire emergency (2J(3))

3 . Doors to outdoors i n stairshafts not held open during a fire emergency (2J(3))

A i r moving fans are stopped i n a system that serves more than two storeys (2J(4))

M e a s u r e J s a t i s f i e s N B C s e n t e n c e

3.

2. 6. 2 ( 7 ) f o r g r o u p s A, C, D, E o r F, M a j o r O c c u p a n c y C l a s s i f i c a t i o n L i m i t o n p o p u l a t i o n ( N B C s e n t e n c e

3.

2. 6. 2 ( 7 ) ) L i m i t e d t o b u i l d i n g s n o t m o r e t h a n 2 5 0 f t h i g h ( N B C s e n t e n c e

3.

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M E A S U R E K. V E R T I C A L L Y D I V I DED B U I L D I N G w i t h s p a t i a l s e p a r a t i o n

1 . Door to outdoors i n each stairshaft held open during a fire emergency (2K(13))

2. O n e firefighters' elevator and one stairshaft i n each smoke control region (2K(4))

3. I f bridges do not occur at each storey two

stairshafts are required i n each smoke control region (NBC 3.4.2.1.)

4 . Building designed as two smoke control regions w i t h spatial separation between (2K(2))

5 . Bridge at each storey or a t intervals not exceeding f i v e storeys (2K(3))

Bridge vented to outdoors or pressurized _{( 2 K ( l l ) )}

6. Fire separation i n storeys below grade to maintain separation be tween smoke control regions _{(2K (1 5))} A i r moving fans are stopped i n a system that serves more than two storeys i n a fire emergency (2K(14))

F i g u r e 1 1 T y p i c a l F l o o r P l a n , M e a s u r e K M e a s u r e K s a t i s f i e s N B C s e n t e n c e 3. 2 . 6 . 2 ( 5 ) f o r b l ~ i l d i n g s o f g r o u p s A, D, E, o r F , M a j o r O c c u p a n c y C l a s s i f i c a t i o n o f a n y h e i g h t M e a s u r e K s a t i s f i e s N B C s e n t e n c e 3. 2 . 6 . 2 ( 5 ) f o r b u i l d i n g s o f g r o u p C M a j o r O c c u p a n c y C l a s s i f i c a t i o n t h a t a r e n o t m o r e t h a n 2 5 0 f t h i g h Copyright © NRC 1941 - 2019 World Rights Reserved © CNRC 1941-2019 Droits réservés pour tous pays

(21)

M E A S U R E K. V E R T I C A L L Y D l V l DED B U I L D I N G w i t h f i r e s e p a r a t i o n

1 . Door to outdoors i n each stairshaft held open during a fire emergency (2K(13))

2. O n e firefighters1 elevator and one stairshaft i n each smoke control region (2K(4))

I f vestibules do not occur at each storey two stairshafts are required i n each smoke control region. (NBC 3.4.2.1 .)

3 . Building designed as two smoke control regions w i t h fire separation between (2K(2))

Fire separation i n storeys below grade to maintain separation between smoke control regions _(2K(15))

4 . Vestibule at each storey or a t intervals not exceeding five storeys (2 K(3))

Vestibules vented to outdoors or pressurized

(2K(11))

5 . Vent to outdoors i n each smoke control region on floors below m i d height o f b u i l d i n g _(2K(12)) A i r moving fans are stopped i n a system that serves more than two storeys during a fire emergency (2K(14)) F i g u r e 1 2 T y p i c a l F l o o r P l a n , M e a s u r e K M e a s u r e K s a t i s f i e s N B C s e n t e n c e 3. 2. 6. 2 ( 5 ) f o r b u i l d i n g s o r g r o u p s A, Dl E , o r F, M a j o r O c c u p a n c y C l a s s i f i c a t i o n o f a n y h e i g h t M e a s l ~ r e K s a t i s f i e s N B C s e n t e n c e 3. 2 . 6 . 2 ( 5 ) f o r b u i l d i n g s o f g r o u p C M a j o r O c c u p a n c y C l a s s i f i c a t i o n t h a t a r e n o t m o r e t h a n 2 5 0 f t h i g h Copyright © NRC 1941 - 2019 World Rights Reserved © CNRC 1941-2019 Droits réservés pour tous pays

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M E A S U R E I. A R E A S O F R E F U G E t w o a r e a s o f r e f u g e o n e a c h f l o o r

1

.

Stainhaft and firefighters' elevator shaft protected by area of refuge (2L(10))

Door to outdoors i n each stairshaft held open during a fire emergency (2L(13))

Stairshaft serving floors below the lowest exit level is separate from stairshaft serving floors above that level (2L(14))

Stainhaft serving floors below the lowest e x i t level is pressurized during a fire emergency (2L(14))

2. Two areas of refuge on each floor pressurized during a fire emergency (see figure (14) for area of refuge every f i f t h floor

(2L(9))

3. N o special protection against smoke for elevator shafts or vertical service spaces other than firefighters' elevator

4. Firefighters' elevator shaft terminates not lower than the first floor below the lowest exit storey or has vestibules at each elevator door i n lower storeys (2L(12))

Firefighters'elevator shaft provided with vent to outdoors a t top and bottom during a fire emergency _(2L(15))

A i r moving fans are stopped i n a system that serves more than two storeys during a fire emergency (2L(18))

F i g u r e 1 3 T y p i c a l F l o o r P l a n , M e a s u r e L M e a s u r e I s a t i s f i e s N B C s e n t e n c e 3. 2.6. 2 ( 5 ) f o r b u i l d i n g s o f g r o u p s A , D, E,or F, M a j o r O c c u p a n c y C l a s s i f i c a t i o n o f a n y h e i g h t M e a s u r e L s a t i s f i e s N B C s e n t e n c e 3. 2.6. 2 ( 5 ) f o r b u i l d i n g s o f g r o u p C M a j o r O c c u p a n c y C l a s s i f i c a t i o n t h a t a r e n o t m o r e t h a n 2 5 0 f t h i g h Copyright © NRC 1941 - 2019 World Rights Reserved © CNRC 1941-2019 Droits réservés pour tous pays

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M E A S U R E L. A R E A S OF REFUGE

d u p l i c a t e g r o u p s o f a r e a s o f r e f u g e a t e v e r y f i f t h s t o r e y

Area o f refuge

1 . Stainhaft and firefighters'elevator shaft protected by area o f refuge or vestibule (2L(10))

Door to outdoors i n each stairshaft held open during a fire emergency (2L(13))

Stainhaft servinq f l o o n below the lowest e x i t level is separate from stairshaft serving floors above that storey (2L(14))

Stairshaft serving floors below the lowest e x i t level is pressurized during a fire emergency (2L(14))

2 . Stainhaft and firefighters' elevator shaft protected i n intermediate floors by pressurized vestibules (2L(10))

3 . Firefighters' elevator shaft terminates not lower than the first floor below the lowest e x i t storey or has vestibules at each elevator door i n lower storeys (2L(12))

Firefighters' elevator shaft provided w i t h vent to outdoors at top and bottom during a fire emergency (2L(15))

4 . N o special protection against smoke for elevator shafts or vertical service spaces other than firefighters' elevator

5. Two areas of refuge on each fifth floor pressurized during a fire emergency (2L(9)) or areas of refuge may be staggered on intermediate floors see (fig. 15) A i r moving fans are stopped in a system that serves more than two storeys i n a fire emergency (2L(18))

F i g u r e 1 4 Typical F l o o r P l a n , M e a s u r e L F i g u r e 1 5 T y p i c a l C r o s s S e c t i o n s h o w i n g A r e a s o f R e f u g e o n I n t e r m e d i a t e F l o o r s M e a s u r e L s a t i s f i e s N B C s e n t e n c e 3. 2 . 6 . 2 ( 5 ) f o r b u i l d i n g s o f g r o u p s A, D, E , o r F, M a j o r O c c u p a n c y C l a s s i f i c a t i o n o f a n y h e i g h t M e a s u r e L s a t i s f i e s N B C s e n t e n c e 3. 2.6. 2 ( 5 ) f o r b u i l d i n g s o f g r o u p C M a j o r O c c u p a n c y C l a s s i f i c a t i o n t h a t a r e n o t m o r e t h a n 2 5 0 f t h i g h Copyright © NRC 1941 - 2019 World Rights Reserved © CNRC 1941-2019 Droits réservés pour tous pays

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-

20

-

M E A S U R E M . B U I L D I N G W I T H B A L C O N I E S

F i g u r e 1 6 T y p i c a l F l o o r P l a n , M e a s u r e M

1 . Door to outdoors i n each stairshaft held open during a fire emergency (2M(2))

Stairshaft serving floors below the lowest e x i t l e v e l is separate from stairshaft serving floors above that level

(2M(3))

Stairshaft serving floors below the e x i t level is pressurized during a fire emergency. (2M(3))

2. Each suite provided w i t h a balcony. (NBC 3.2.6.2. (8))

3 . Elevator shaft terminates not lower than the first floor below the lowest e x i t storey or has vestibules a t each elevator door i n lower storeys (2M(4))

A i r moving fans are stopped i n a system that serves more than two storeys i n a fire emergency (2M(5))

M e a s u r e M s a t i s f i e s N B C s e n t e n c e

3.

2. 6. 2 ( 8 )

f o r b u i l d i n g s o f g r o u p C M a j o r

O c c u p a n c y C l a s s i f i c a t i o n t h a t a r e n o t m o r e t h a n 1 2 0 f t h i g h

(25)

F i g u r e 1 7 S e c t i o n t h r o u g h B u i l d i n g s L i n k e d b y U n d e r g r o u n d T u n n e l

BUILDING A

2. Vestibules Vented to Outdoors or Pressurized

1

.

Vestibule Vented to Outdoors or Pressurized F i g u r e 1 8 S e c t i o n t h r o u g h B u i l d i n g s J o i n e d a t F i r e w a l l BUILDING A \\

M e a s u r e N s a t i s f i e s N B C s e n t e n c e

3. 2. 6. 2. ( 9 ) f o r c o n n e c t e d

b u i l d i n g s

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CHAPTER 2

MEASURES FOR L I F E SAFETY IN HIGH BUILDINGS

Section 2 ( a )

-

F u l l y S p r i n k l e r e d Buildings M e a s u r e A

-

G e n e r a l T h e m e a s u r e s d e s c r i b e d in t h i s s e c t i o n m a y b e c o n s i d e r e d to b e a n adequate s m o k e c o n t r o l m e a s u r e , satisfying t h e r e q u i r e m e n t s of

N B C

Sentence 3 . 2 . 6 . 2 . ( 6 ) . R e l i a n c e i s p l a c e d o n the f u l l s p r i n k l e r i n s t a l l a t i o n t o l i m i t f i r e s p r e a d and hence t h e g e n e r a t i o n of s m o k e .

Some additional p r o t e c t i o n of exit s t a i r s is afforded by t h e p r o v i s i o n of a n opening t o t h e outdoors a t t h e foot of t h e s t a i r s h a f t . I n

cold w e a t h e r , when s t a c k a c t i o n i s likely t o b e m o s t s i g n i f i c a n t , t h i s m e a s u r e m a y give a g e n e r a l i n c r e a s e in a i r p r e s s u r e in t h e s t a i r s h a f t , t h u s r e s t r i c t i n g e n t r y of s m o k e .

I n t h i s s e c t i o n i s included t h e r e q u i r e m e n t t h a t e l e v a t o r and s e r v i c e s h a f t s should not be continuous f r o m above to below g r a d e e x c e p t when v e s t i b u l e s a r e p r o v i d e d a t e l e v a t o r d o o r s i n below g r a d e s t o r e y s .

W h e r e M e a s u r e A. i s adopted and a f i r e i s d e t e c t e d by a n

a u t o m a t i c d e v i c e o r a f i r e a l a r m box i s a c t i v a t e d m a n u a l l y , it i s intended t h a t a f i r e a l a r m will sound o n a l l f l o o r s s i m u l t a n e o u s l y , and that t h e o c c u p a n t s of t h e f i r e f l o o r w i l l walk down s t a i r s to t h e s t r e e t f l o o r o r to a s a f e i n t e r m e d i a t e f l o o r a r e a . Occupants of o t h e r f l o o r s m a y r e m a i n u n t i l a d v i s e d t o evacuate by t h e p e r s o n o p e r a t i n g t h e c e n t r a l a l a r m and c o n t r o l f a c i l i t y . M e a s u r e A

-

R e q u i r e m e n t s i n S p r i n k l e r e d Buildings (1) The r e q u i r e m e n t s of NBC Sentence 3 . 2 . 6 . 2 . (6) m a y b e m e t by i n c o r p o r a t i n g t h e r e q u i r e m e n t s in S e n t e n c e s ( 2 ) t o ( 8 ) .

( 2 ) A s t a i r w a y s e r v i n g s t o r e y s above t h e lowest exit l e v e l h a s a vent o r d o o r t o t h e o u t d o o r s a t o r n e a r t h e b o t t o m of t h e s t a i r s h a f t , a s d e s c r i b e d i n Sentence ( 4 ) .

( 3 ) A s t a i r w a y s e r v i n g f l o o r s below t h e lowest exit l e v e l

( a ) has a vent o r d o o r to t h e o u t d o o r s a t o r n e a r t h e t o p of t h e s t a i r s h a f t a s d e s c r i b e d i n ( 4 ) ( b ) i s enclosed i n a s h a f t t h a t d o e s not p a s s t h r o u g h t h e f l o o r above t h e l o w e s t exit l e v e l a n d i s s e p a r a t e f r o m a s h a f t

-

2 2

-

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t h a t contains a s t a i r w a y s e r v i n g upper s t o r e y s , o r i s e n c l o s e d i n a s h a f t t h a t contains a s t a i r w a y s e r v i n g u p p e r s t o r e y s , but i s s e p a r a t e d f r o m t h a t s t a i r w a y a t the l o w e s t exit l e v e l by a f i r e s e p a r a t i o n , a n d

( c ) i s provided with e q u i p m e n t c a p a b l e of m a i n t a i n i n g a flow of a i r i n t r o d u c e d a t o r n e a r t h e b o t t o m of t h e s t a i r s h a f t , a t a r a t e equal to a t l e a s t 1000 c f m f o r e a c h s t o r e y s e r v e d by the s t a i r w a y .

( 4 ) A s t a i r s h a f t r e q u i r e d to b e v e n t e d t o t h e o u t d o o r s by ( 2 ) o r ( 3 ) o r by o t h e r p r o v i s i o n s i n t h i s Supplement i s p r o v i d e d with a vent o r d o o r t h a t

( a ) h a s a n openable a r e a of 0. 5 s q . f t . f o r e v e r y d o o r between t h e s t a i r s h a f t and a f l o o r a r e a but not l e s s t h a n 20 s q . f t .

,

( b ) opens d i r e c t l y to the o u t d o o r s o r into a v e s t i b u l e o r exit c o r r i d o r that h a s a s i m i l a r opening to t h e o u t d o o r s , and ( c ) h a s a door o r c l o s u r e t h a t i s openable m a n u a l l y and c a n

r e m a i n i n t h i s open position d u r i n g a f i r e e m e r g e n c y . ( 5 ) An e l e v a t o r s h a f t t h a t p a s s e s t h r o u g h t h e f l o o r above the l o w e s t e x i t s t o r e y does not p e n e t r a t e t h e f l o o r of t h e next s t o r e y i m m e d i a t e l y below t h a t s t o r e y , except w h e r e t h e r e is a v e s t i b u l e between t h e shaft and

e a c h below g r a d e f l o o r a r e a a s i s d e s c r i b e d i n Sentence ( 3 ) of M e a s u r e D ( P * 36 ) *

( 6 )

A v e r t i c a l s e r v i c e s p a c e , o t h e r than a n e l e v a t o r s h a f t that

p a s s e s t h r o u g h the f l o o r above t h e l o w e s t exit s t o r e y , i s p r o v i d e d with a tight fitting non-combustible s e a l o r f i r e s t o p a t the f l o o r l e v e l of the s t o r e y i m m e d i a t e l y below t h a t s t o r e y , except w h e r e t h e v e r t i c a l s e r v i c e s p a c e i s vented t o t h e o u t d o o r s a t the top a s d e s c r i b e d i n Sentence ZF(10).

( 7 ) A supply of a i r r e q u i r e d b y ( 3 ) i s c a r r i e d i n d u c t s a s d e s c r i b e d in S e n t e n c e (13) of M e a s u r e F ( p . 4 9 ) . ( 8 ) The c e n t r a l c o n t r o l f a c i l i t y r e q u i r e d by N B C A r t i c l e 3 . 2 . 6. 8. i s p r o v i d e d with a d d i t i o n a l c o n t r o l s c a p a b l e of ( a ) opening c l o s u r e s to v e n t s i n s h a f t s that m a y b e r e q u i r e d by (6)s Copyright © NRC 1941 - 2019 World Rights Reserved © CNRC 1941-2019 Droits réservés pour tous pays

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( b ) stopping a i r handling s y s t e m s a s r e q u i r e d b y N B C S e n t e n c e 3 . 2 . 6 . 2 , ( 6 ) , and ( c ) i n i t i a t i n g t h e m e c h a n i c a l a i r s u p p l y t o s t a i r s h a f t s a s m a y b e r e q u i r e d i n ( 3 ) . Copyright © NRC 1941 - 2019 World Rights Reserved © CNRC 1941-2019 Droits réservés pour tous pays

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S e c t i o n 2(b) O p e n C o r r i d o r A c c e s s t o S t a i r s and E l e v a t o r s M e a s u r e s B a n d C

-

G e n e r a l M e a s u r e s B a n d C c a n b e a p p l i e d t o a building w h e r e h a b i t a b l e f l o o r a r e a s a r e a p p r o a c h e d along a c c e s s w a y s o p e n to t h e o u t d o o r s . E a c h c o r r i d o r t h a t p r o v i d e s a c c e s s to s t a i r s o r e l e v a t o r s i s p e r m a n e n t l y o p e n to the o u t s i d e a s shown i n Fig. 2 and 19. T h e

s i t u a t i o n i s i l l u s t r a t e d by t h e p r e s s u r e c h a r a c t e r i s t i c d i a g r a m shown i n Fig. 20. A i r flow t h r o u g h openings t h a t m a y e x i s t i n f l o o r s is l i k e l y to b e m o r e p r o n o u n c e d t h a n with o t h e r s m o k e c o n t r o l m e t h o d s b e c a u s e of t h e r e d u c t i o n i n the i n f l u e n c e of v e r t i c a l s h a f t s , so i t i s d e s i r a b l e t h a t o p e n i n g s t h r o u g h t h e f l o o r - c e i l i n g a s s e m b l y b e m i n i m i z e d . T h i s should n o t , h o w e v e r , p r e s e n t a n i m m e d i a t e s m o k e p r o b l e m e x c e p t o n t h e f l o o r d i r e c t l y a b o v e t h e f l o o r w h e r e a f i r e o c c u r s . M e a s u r e C i s t h e s a m e as M e a s u r e B e x c e p t t h a t no s t e p s a r e t a k e n to l i m i t s m o k e m o v e m e n t i n t o u p p e r s t o r e y s t h r o u g h v e r t i c a l s e r v i c e s p a c e s o r s h a f t s i n M e a s u r e C. W h e r e s h a f t s e n c l o s i n g plumbing a n d e l e c t r i c a l s e r v i c e s p e n e t r a t e f l o o r s p a c e s a n d a d e c i s i o n h a s b e e n m a d e t o u s e M e a s u r e B f o r c o n t r o l of s m o k e m o v e m e n t , t h e s e s h a f t s s h o u l d b e s e a l e d a t l e a s t a t e v e r y fith s t o r e y a t a h o r i z o n t a l f i r e s e p a r a t i o n a n d a t t h e f l o o r i m m e d i a t e l y below t h e l o w e s t e x i t s t o r e y o r h a v e v e n t s t o t h e o u t s i d e a t t h e t o p . I n t h e l a t t e r c a s e t h e r e is still s o m e p o s s i b i l i t y t h a t s m o k e m a y p a s s into t h e u p p e r m o s t f l o o r b e c a u s e t h e a i r p r e s s u r e s i n t h e s e f l o o r a r e a s a r e i n t h e s a m e r a n g e as t h e o u t s i d e p r e s s u r e s . It is t h e r e f o r e of i m p o r t a n c e t h a t any l e a k a g e a r e a s i n t h e e n c l o s i n g w a l l s b e t w e e n f l o o r a r e a s and s h a f t b e kept t o a m i n i m u m . In o r d e r to a v o i d c r e a t i o n of p r e s s u r e s t h a t m a y i n t e r f e r e w i t h t h e opening of d o o r s t o s t a i r s a n d e l e v a t o r s h a f t s , i t i s r e c o m m e n d e d t h a t t h e building h e a t i n g s y s t e m b e s o d e s i g n e d t h a t t e m p e r a t u r e s i n s t a i r s a n d

e l e v a t o r s h a f t s , if h e a t e d , will not e x c e e d 2 0 F d e g r e e s a b o v e o u t s i d e air t e m p e r a t u r e .

W h e r e M e a s u r e B i s a d o p t e d , a n d a f i r e i s d e t e c t e d b y a n

a u t o m a t i c device, o r a f i r e a l a r m box is a c t i v a t e d m a n u a l l y , it is intended t h a t a f i r e a l a r m w i l l sound o n all f l o o r s s i m u l t a n e o u s l y , and t h a t t h e o c c u p a n t s of t h e f i r e f l o o r w i l l walk down s t a i r s t o a s a f e f l o o r a r e a . O c c u p a n t s of o t h e r f l o o r s m a y r e m a i n u n t i l a d v i s e d to e v a c u a t e by the p e r s o n o p e r a t i n g t h e c e n t r a l a l a r m and c o n t r o l f a c i l i t y . Copyright © NRC 1941 - 2019 World Rights Reserved © CNRC 1941-2019 Droits réservés pour tous pays

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I

PERMANENT

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CORRIDOR OR BALCONY PERMANENT

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r

_{O P E N I N G} CORRIDOR OR BALCONY

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F i g u r e 1 9 I l l u s t r a t i o n o f M e t h o d B a n d C D e s i g n SECTION THROUGH CORRIDORS OR BALCONIES Copyright © NRC 1941 - 2019 World Rights Reserved © CNRC 1941-2019 Droits réservés pour tous pays

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O U T S I D E A I R PRESSURE PRESSLIRE I N F L O O R A R E A S F L O O R A R E A S

-7

S E C T I O N T H R O U G H B U I L D I N G PRESSURE C H A R A C T E R I S T I C S S H O W I N G A I R F L O W L O W E R H I G H E R

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F i g u r e 2 0 P r e s s u r e C h a r a c t e r i s t i c s i n a M e t h o d B D e s i g n

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Where M e a s u r e C i s adopted, and a f i r e i s d e t e c t e d by a n a u t o m a t i c device o r a f i r e a l a r m box i s a c t i v a t e d m a n u a l l y , i t i s

intended that a f i r e a l a r m will sound on a l l f l o o r s s i m u l t a n e o u s l y , a n d t h a t o c c u p a n t s of a l l f l o o r s will walk down s t a i r s to the s t r e e t f l o o r to a s a f e i n t e r m e d i a t e floor a r e a . M e a s u r e B

-

R e q u i r e m e n t s f o r Open C o r r i d o r A c c e s s to S t a i r s and E l e v a t o r s (Including r e s t r i c t i o n s on m o v e m e n t of s m o k e f r o m f l o o r to f l o o r ) 2 (b) (1) The r e q u i r e m e n t s of S e n t e n c e s ( I ) , ( 2 ) and ( 3 ) of NBC A r t i c l e 3.2. 6.2. m a y b e m e t by i n c o r p o r a t i n g the r e q u i r e m e n t s i n S e n t e n c e s (2) to (10).

( 2 ) All public c o r r i d o r s leading t o t h e r e q u i r e d exit s t a i r s a n d f i r e f i g h t e r s ' e l e v a t o r f r o m e v e r y f l o o r a r e a on a f l o o r above t h e l o w e s t exit s t o r e y a r e provided with p e r m a n e n t openings to the o u t d o o r s t h a t

( a ) a r e d i s t r i b u t e d along t h e length of the c o r r i d o r , and ( b ) have the top of t h e opening not m o r e than 10 i n . below the

ceiling of the c o r r i d o r , a n d

( c ) have a n a g g r e g a t e open a r e a that i s not l e s s than 10 p e r c e n t of the f l o o r a r e a of t h e c o r r i d o r o r 10 sq. ft. whichever i s g r e a t e r .

( 3 ) a s t a i r w a y s e r v i n g s t o r e y s below the l o w e s t exit l e v e l ( a ) h a s a vent o r d o o r to t h e o u t d o o r s a t t h e top of the s t a i r -

shaft that i s a s d e s c r i b e d i n Sentence ( 4 ) of M e a s u r e A ( p . 2 3

1.

( b ) i s enclosed i n a s h a f t that does not p a s s t h r o u g h the floor above the l o w e s t exit l e v e l and i s s e p a r a t e f r o m a s h a f t that contains a s t a i r w a y s e r v i n g u p p e r s t o r e y s ; o r is enclosed in a shaft t h a t contains a s t a i r w a y s e r v i n g u p p e r s t o r e y s but i s s e p a r a t e d f r o m that s t a i r w a y a t the l o w e s t exit l e v e l by a f i r e s e p a r a t i o n , and

( c ) i s provided with equipment c a p a b l e of maintaining a flow of a i r , introduced a t o r n e a r the bottom of the shaft, a t a r a t e equal to a t l e a s t 1000 c f m f o r e a c h s t o r e y s e r v e d by the s t a i r w a y . Copyright © NRC 1941 - 2019 World Rights Reserved © CNRC 1941-2019 Droits réservés pour tous pays

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( 4 ) An e l e v a t o r shaft that p a s s e s through the f l o o r a b o v e t h e

l o w e s t exit s t o r e y does not p e n e t r a t e t h e f l o o r of the s t o r e y i m m e d i a t e l y below t h a t s t o r e y , except w h e r e t h e r e i s a v e s t i b u l e between t h e shaft and

e a c h f l o o r a r e a below t h e l o w e s t exit s t o r e y , a s d e s c r i b e d i n Sentence ( 3 )

of M e a s u r e D (p. 36 ).

( 5 ) A v e r t i c a l s e r v i c e s p a c e within a h e a t e d f l o o r a r e a o t h e r than a n e l e v a t o r s h a f t i s p r o v i d e d with

( a ) tight fitting n o n - c o m b u s t i b l e f i r e s t o p s l o c a t e d a t t h e l e v e l of t h e floor i m m e d i a t e l y below t h e l o w e s t exit s t o r e y and

a t t h e l e v e l of c e r t a i n o t h e r f l o o r s that a r e f i r e s e p a r a t i o n s , provided the s p a c e b e t w e e n f i r e s t o p s d o e s not e x c e e d 5 s t o r e y s , o r

( b ) a vent to the o u t d o o r s a s d e s c r i b e d i n S e n t e n c e (10) of M e a s u r e

F

(p. 48 ).

( 6 )

An e l e v a t o r s h a f t within a h e a t e d f l o o r a r e a , o t h e r

t h a n a s h a f t t h a t contains a f i r e f i g h t e r s 1 e l e v a t o r , i s p r o v i d e d with a vent to the o u t d o o r s a s d e s c r i b e d i n Sentence (10) of M e a s u r e F ( p . 48), and is p r o t e c t e d a g a i n s t e n t r y of s m o k e a s d e s c r i b e d i n M e a s u r e D (p. 3 6 ) o r M e a s u r e F ( p . 47 ).

( 7 ) Except f o r e x h a u s t f r o m k i t c h e n s , w a s h r o o m s and b a t h r o o m s i n dwelling u n i t s , a i r moving f a n s a r e stopped i n a n a i r handling s y s t e m t h a t s e r v e s m o r e than two s t o r e y s .

(8) Supply, r e t u r n and e x h a u s t ducts exceeding 20 sq. in.

i n c r o s s - s e c t i o n a l a r e a a t the point of e n t r y to a v e r t i c a l s e r v i c e s p a c e in a n a i r handling s y s t e m that i s r e q u i r e d to s h u t down by t h e p r o v i s i o n s of ( 7 ) a r e p r o v i d e d with d a m p e r s that will c l o s e when the a i r moving f a n s a r e stopped.

( 9 ) W h e r e a supply of a i r i s r e q u i r e d by t h e p r o v i s i o n s of S e n t e n c e ( 3 ) i t i s c a r r i e d in ducts d e s c r i b e d in Sentence (13) of M e a s u r e F

( P O 49

1-

(10) The c e n t r a l a l a r m and c o n t r o l f a c i l i t y r e q u i r e d by N B C A r t i c l e 3.2. 6. 8. i s provided with a d d i t i o n a l c o n t r o l s that a r e c a p a b l e of

( a ) stopping t h e a i r handling s y s t e m s a n d c l o s i n g d a m p e r s a s r e q u i r e d by ( 7 ) a n d ( 8 ) , ( b ) opening c l o s u r e s to v e n t s i n v e r t i c a l s e r v i c e s p a c e s w h e r e r e q u i r e d by ( 5 ) a n d ( 6 ) , a n d Copyright © NRC 1941 - 2019 World Rights Reserved © CNRC 1941-2019 Droits réservés pour tous pays

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( c ) i n i t i a t i n g t h e a i r s u p p l y t o s t a i r s h a f t s a s m a y b e r e q u i r e d b y ( 3 ) . M e a s u r e C - R e q u i r e m e n t s f o r Open C o r r i d o r A c c e s s to S t a i r s a n d E l e v a t o r s ( n o r e s t r i c t i o n o n m o v e m e n t of s m o k e f r o m f l o o r to f l o o r ) 2 (b) (1) T h e r e q u i r e m e n t s of S e n t e n c e s ( 2 ) a n d ( 3 ) of N B C A r t i c l e 3 . 2 . 6 . 2 . , m a y b e m e t b y i n c o r p o r a t i n g t h e r e q u i r e m e n t s of S e n t e n c e s ( 2 ) to ( 7 ) . ( 2 ) T h e p u b l i c c o r r i d o r s l e a d i n g to t h e r e q u i r e d e x i t s t a i r s a n d f i r e f i g h t e r s ' e l e v a t o r f r o m e v e r y f l o o r a r e a o n a f l o o r a b o v e t h e s t o r e y o n w h i c h e g r e s s d i r e c t l y to t h e o u t d o o r s o c c u r s a r e p r o v i d e d with p e r m a n e n t o p e n i n g s to t h e o u t d o o r s t h a t ( a ) a r e d i s t r i b u t e d a l o n g t h e l e n g t h of t h e c o r r i d o r

( b ) h a v e t h e top of t h e o p e n i n g not m o r e t h a n 10 in. b e l o w t h e c e i l i n g of t h e c o r r i d o r , a n d ( c ) h a v e a n a g g r e g a t e o p e n a r e a t h a t i s not l e s s t h a n 10 p e r c e n t of t h e f l o o r a r e a of t h e c o r r i d o r o r 10 s q . ft. w h i c h e v e r is g r e a t e r . ( 3 ) A s t a i r w a y s e r v i n g s t o r e y s below t h e l o w e s t e x i t l e v e l ( a ) h a s a v e n t o r d o o r to t h e o u t d o o r s a t t h e top of t h e s t a i r - s h a f t a s d e s c r i b e d i n S e n t e n c e ( 4 ) of M e a s u r e A ( p . 23 ). ( b ) i s e n c l o s e d i n a s h a f t t h a t d o e s not p a s s t h r o u g h t h e f l o o r a b o v e t h e l o w e s t e x i t s t o r e y a n d is s e p a r a t e f r o m a s h a f t t h a t c o n t a i n s a s t a i r w a y s e r v i n g u p p e r s t o r e y s ; o r i s e n c l o s e d i n a s h a f t t h a t c o n t a i n s a s t a i r w a y s e r v i n g u p p e r s t o r e y s , b u t is s e p a r a t e d f r o m t h a t s t a i r w a y a t t h e l o w e s t e x i t l e v e l b y a f i r e s e p a r a t i o n , and ( c ) i s p r o v i d e d with e q u i p m e n t c a p a b l e of m a i n t a i n i n g a flow of a i r , i n t r o d u c e d a t o r n e a r t h e b o t t o m of t h e s h a f t , of a t l e a s t 1000 c f m f o r e a c h s t o r e y s e r v e d by t h e s t a i r w a y . ( 4 ) A n e l e v a t o r s h a f t t h a t c o n t a i n s a f i r e f i g h t e r s 1 e l e v a t o r a n d p a s s e s t h r o u g h t h e f l o o r a b o v e t h e l o w e s t e x i t l e v e l d o e s not p e n e t r a t e t h e f l o o r of t h e s t o r e y i m m e d i a t e l y b e l o w t h a t s t o r e y , e x c e p t w h e r e t h e r e i s a Copyright © NRC 1941 - 2019 World Rights Reserved © CNRC 1941-2019 Droits réservés pour tous pays

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v e s t i b u l e between the s h a f t and e a c h f l o o r a r e a below t h e l o w e s t exit s t o r e y a s d e s c r i b e d in Sentence ( 3 ) of M e a s u r e D _(p.₃₆ _).

( 5 ) Except f o r exhaust f r o m k i t c h e n s , w a s h r o o m s and b a t h r o o m s in dwelling u n i t s , a i r moving f a n s a r e stopped i n a n a i r handling s y s t e m that s e r v e s m o r e than two s t o r e y s .

( 6 ) Where a supply of a i r i s r e q u i r e d by ( 3 ) , i t i s c a r r i e d i n

ducts d e s c r i b e d in Sentence (13) of M e a s u r e

F

_{( p . 49} _).

( 7 ) The c e n t r a l a l a r m and c o n t r o l f a c i l i t y r e q u i r e d by N B C

A r t i c l e 3 . 2 . 6. 8. i s provided with additional c o n t r o l s that a r e c a p a b l e of

( a ) stopping t h e a i r handling s y s t e m s a s r e q u i r e d b y ( 5 ) and ( b ) initiating the a i r supply to s t a i r s h a f t s a s m a y b e r e q u i r e d