Ventilation measurements in a basement fallout shelter

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Ventilation measurements in a basement fallout shelter

NATIONAL RESEARCH COUNCIL CANADA

DIVISION O F BUILDING RESEARCH

VENTILATION MEASUREMENTS IN A BASEMENT F A L L O U T S H E L T E R b y G. T . T a m u r a I n t e r n a l R e p o r t . No. 246 of t h e Division of Building R e s e a r c h OTTAWA M a r c h 1962

P R E F A C E

T h e Government of Canada h a s published a booklet,

Blueprint f o r Survival No. 1, "Your B a s e m e n t Fallout S h e l t e r , and h a s r e c o m m e n d e d t h e construction of fallout s h e l t e r s t o t h e g e n e r a l public. T h e Division h a s undertaken t o study s o m e of the p r o b l e m s of heating and ventilating of s u c h s h e l t e r s , a s a n a s s i s t a n c e t o t h e

E m e r g e n c y M e a s u r e s Organization. A s h e l t e r of t h e type r e c o m m e n d e d h a s been constructed in a house m a d e available for the p u r p o s e by

E M 0 through C e n t r a l Mortgage and Housing Corporation and h a s been under study for t h e p a s t y e a r . The r e s u l t s of the two winter t r i a l s and two s u m m e r t r i a l s thus f a r conducted a r e d e s c r i b e d i n DBR I n t e r n a l R e p o r t No. 243. T h e ventilation m e a s u r e m e n t s a r e now d e s c r i b e d for t h e benefit of t h o s e having s p e c i a l i n t e r e s t in such techniques, t h e r e s u l t s having been s u m m a r i z e d i n the g e n e r a l r e p o r t .

T h e author, a m e c h a n i c a l engineer and a r e s e a r c h officer with t h e Building S e r v i c e s Section, h a s been engaged on s t u d i e s of chimneys and of the indoor c l i m a t e of dwellings with s p e c i a l r e f e r e n c e to ventilation.

Ottawa M a r c h 1962

N. B. Hutcheon, A s s i s t a n t D i r e c t o r .

VENTILATION MEASUREMENTS IN A BASEMENT FALLOUT SHELTER

G. T . T a m u r a

A s e r i e s of t e s t s was c a r r i e d out to m e a s u r e the n a t u r a l ventilation r a t e s of t h e s h e l t e r and t h e b a s e m e n t , a s p a r t of t h e

fallout s h e l t e r s t u d i e s on b a s e m e n t and s h e l t e r c l i m a t e being conducted b y t h e Division of Building R e s e a r c h . T h e ventilation m e a s u r e m e n t s w e r e obtained d u r i n g t h e winter and s u m m e r t r i a l s a s d e s c r i b e d

in the DBR R e p o r t No. 243 " B a s e m e n t Fallout Shelter C l i m a t e Studies l961I1 ( 1 ) .

T h e r a t e of s h e l t e r ventilation i s one of the f a c t o r s t h a t a f f e c t s t h e living conditions within a fallout s h e l t e r . B e c a u s e t h e a i r drawn into t h e s h e l t e r f r o m t h e b a s e m e n t is a m i x t u r e of the outdoor a i r and t h e a i r exhausted f r o m t h e s h e l t e r , t h e b a s e m e n t ventilation r a t e a l s o influences the s h e l t e r c l i m a t e . T h e s e ventilation r a t e s affect t h e t e m p e r a t u r e , humidity and t h e dour l e v e l of the a i r i n s i d e t h e

s h e l t e r . They a l s o affect the oxygen and c a r b o n dioxide content in the s h e l t e r a i r by supplying f r e s h a i r and displacing a i r consumed and expelled b y t h e occupants and b y t h e h e a t e r s and l a m p s u s e d for cooking, h e a t i n g and lighting.

T h e s h e l t e r and b a s e m e n t ventilation r a t e s w e r e obtained during t e s t No. 1 (unheated t r i a l s ) and t e s t No. 2 (heated t r i a l s ) of t h e winter t e s t s e r i e s with t h e door c l o s e d t o c o n s e r v e h e a t i n s i d e t h e s h e l t e r . B e c a u s e t h e door to t h e s h e l t e r was left open during t e s t s Nos. 3 and 4, p e r m i t t i n g u n r e s t r i c t e d exchange between s h e l t e r and b a s e m e n t a i r , b a s e m e n t ventilation r a t e s only w e r e r e c o r d e d during t h e s u m m e r t e s t s . T h e r e s u l t s of t h e s e ventilation t e s t s a r e now r e p o r t e d .

Method

T h e ventilation r a t e s of t h e fallout s h e l t e r and t h e b a s e m e n t w e r e d e t e r m i n e d by the t r a c e r g a s technique using h e l i u m a s t h e t r a c e r . T h e t h e r m a l conductivity of the helium g a s i s s i x t i m e s t h a t of a i r and t h e v a r i a t i o n of t h e t h e r m a l conductivity of t h e t r a c e r g a s - a i r m i x t u r e i s m e a s u r e d t o d e t e r m i n e the r a t e of d e c a y of helium concentration with t h e a i r change in the e n c l o s u r e . T h e change i n t h e t h e r m a l c o n - ductivity of t h e t r a c e r g a s - a i r m i x t u r e was m e a s u r e d u s i n g t h e

k a t h a r o m e t e r designed by t h e National B u r e a u of S t a n d a r d s (2) with c e r t a i n design modifications.

A s s u m i n g a homogeneous m i x t u r e of helium and a i r throughout the e n c l o s u r e , the r e l a t i o n between t h e change in helium concentration and t h e ventilation r a t e i s given by:

w h e r e V

=

volume of e n c l o s u r e

K

=

a i r i n f i l t r a t i o n r a t e

c = volume concentration of helium t = t i m e .

Integration of t h i s e x p r e s s i o n gives:

K

w h e r e

-

-

v

-

a i r change r a t e

At constant ventilation r a t e t h e plot of concentration v e r s u s t i m e gives a s t r a i g h t l i n e on s e m i - l o g a r i t h m i c g r a p h p a p e r .

After t h e helium i s r e l e a s e d in t h e s h e l t e r , s o m e of i t l e a v e s t h e s h e l t e r a s a r e s u l t of ventilation and e n t e r s the b a s e m e n t . P a r t of i t r e t u r n s to t h e s h e l t e r and the r e m a i n d e r flows u p s t a i r s and

o u t d o o r s owing t o t h e ventilation of t h e b a s e m e n t . B e c a u s e t h e volume of the b a s e m e n t i s a p p r o x i m a t e l y t e n t i m e s t h a t of t h e s h e l t e r , t h e r e s u l t a n t helium concentration in t h e b a s e m e n t a s c o m p a r e d with that of the s h e l t e r i s quite low. Since t h e b a s e m e n t ventilation r a t e i s s m a l l , t h e r a t e of decay of helium i s lower in the b a s e m e n t . Over the s h o r t p e r i o d when t h e ventilation r a t e is d e t e r m i n e d t h i s b a s e m e n t

concentration i s a s s u m e d t o be constant. T h e r e f o r e t h e helium concen- t r a t i o n in t h e b a s e m e n t should be s u b t r a c t e d f r o m t h e helium concen- t r a t i o n in t h e s h e l t e r t o obtain t h e c o r r e c t ventilation r a t e of t h e

s h e l t e r . T h e equation for the s h e l t e r ventilation r a t e would then b e c o m e :

w h e r e c = helium concentration in s h e l t e r c , = helium concentration in b a s e m e n t .

Two k a t h a r o m e t e r s and t h e i r a n c i l l a r y r e c o r d i n g equipment w e r e used to m e a s u r e the helium concentration in the b a s e m e n t a s well a s i n the

s h e l t e r . The basement h a s two horizontally pivoted windows with a total l i n e a l ' c r a c k of 16. 2 _{ft. T h e s e windows w e r e fitted with} s t o r m windows and w e r e not weatherstripped.

T h e k a t h a r o m e t e r used for m e a s u r i n g helium concentration c o n s i s t s of two matched t h e r m i s t o r s enclosed in the cavities of a b r a s s block. One t h e r m i s t o r (sensing) i s s e a l e d with the exception of four

1/32-in. d i a m e t e r holes in the b r a s s block. T h e other t h e r m i s t o r ( s t a n d a r d ) i s sealed in a g l a s s envelope inside the b r a s s block with one end forming a s m a l l open tube which i s filled with light oil ( F i g . 1 ) .

The t h e r m i s t o r s f o r m the two l e g s of a Wheatstone bridge c i r c u i t ( F i g . 2). T h e helium -air m i x t u r e e n t e r s the cavity that contains the sensing t h e r m i s t o r by diffusion through the s m a l l holes in the b r a s s block. This r e s u l t s in an i n c r e a s e d r a t e of h e a t l o s s f r o m t h e sensing t h e r m i s t o r by a n amount depending on the helium concentration, since the t h e r m a l conductivity of helium i s g r e a t e r than t h a t of a i r . As a r e s u l t of the lowering of t e m p e r a t u r e of the t h e r m i s t o r the e l e c t r i c a l r e s i s t a n c e of the t h e r m i s t o r i s a l t e r e d . T h i s r e s u l t s in an imbalance of the bridge c i r c u i t , which i s m e a s u r e d on a single point millivolt r e c o r d e r

.

Because t h e s e t h e r m i s t o r s a r e sensitive t o ambient a i r t e m p e r a t u r e change, the standard t h e r m i s t o r in a g l a s s envelope which f o r m s the second l e g of the Wheatstone bridge c i r c u i t i s chosen s o that i t s r e s i s t a n c e c h a r a c t e r i s t i c i s closely matched t o that of the sensing t h e r m i s t o r . In t h i s manner any changes in the b r a s s block t e m p e r a t u r e will affect the r e s i s t a n c e s of both t h e r m i s t o r s

equally. Although c a r e i s taken t o m a t c h the t h e r m i s t o r s , deviations in t h e i r c h a r a c t e r i s t i c s do occur and t h e r e f o r e t h e k a t h a r o m e t e r i s mounted on the s i d e of a n insulated copper container filled with w a t e r . With t h i s a r r a n g e m e n t f a i r l y good t e m p e r a t u r e control i s obtained over a s h o r t duration.

It was found that the k a t h a r o m e t e r i s a l s o s e n s i t i v e t o changes in b a r o m e t r i c p r e s s u r e . The oil in the g l a s s tube of the s t a n d a r d t h e r m i s t o r allows for the fluctuation in the b a r o m e t r i c p r e s s u r e s o that the t h e r m i s t o r s a r e subjected to p r e s s u r e s of a

constant difference. In addition t o the change in the b a r o m e t r i c p r e s s u r e , the r e l a t i v e humidity of the a i r m a y a l s o change during the

c o u r s e of a t e s t . T h e r e f o r e the s a m p l e helium a i r m i x t u r e i s p a s s e d through a drying bottle filled with calcium chloride b e f o r e exposing the gas t o the k a t h a r o m e t e r .

In t h i s way t h e effect of t h e changes in t h e a m b i e n t a i r condition on t h e k a t h a r o m e t e r i s reduced. To c o m p e n s a t e f u r t h e r f o r t h i s e f f e c t and, a l s o , f o r the v a r i a t i o n in the d - c power supply voltage, a t h i r d l e g was added t o t h e Wheatstone b r i d g e c i r c u i t . T h i s l e g h a s a fixed r e s i s t o r (200 o h m s ) and the balance between t h e second and t h i r d l e g of the c i r c u i t i s o b s e r v e d with a millivolt a m m e t e r and maintained by adjusting the d - c power supply voltage.

In t h i s m a n n e r the r e s i s t a n c e of t h e s t a n d a r d t h e r m i s t o r i s kept a t a constant value.

The k a t h a r o m e t e r was c a l i b r a t e d in the l a b o r a t o r y by d e t e r m i n i n g t h e a i r change r a t e of a box ( 4 by 8 by 8 f t ) using t h e t r a c e r gas technique and by m e a s u r i n g the a i r flow into the box with a v a r i a b l e a r e a flow m e t e r . T h e r e s u l t of the c a l i b r a t i o n showed c l o s e a g r e e m e n t up t o 4 a i r changes p e r hour but above t h i s r a t e the k a t h a r o m e t e r gave a lower value of a i r change r a t e . T h i s l a c k of a g r e e m e n t was a t t r i b u t e d t o t h e f a c t t h a t t h e r a t e of diffusion of the

s a m p l e helium a i r m i x t u r e into t h e k a t h a r o m e t e r through t h e four 1/32-in. d i a m e t e r h o l e s was not r a p i d enough f o r t h e t h e r m i s t o r t o s e n s e t h e r e a l r a t e of change of helium concentration with t h e ventilation r a t e above 4 a i r changes p e r h o u r . Sufficient t e s t s w e r e

conducted t o obtain a c a l i b r a t i o n c u r v e up t o 10 a i r changes p e r hour

T e s t s

T h e layout of t h e b a s e m e n t ( F i g . 3) shows t h e o r i e n t a t i o n of t h e s h e l t e r in t h e b a s e m e n t and the location of the b a s e m e n t windows. F o u r c o n c r e t e blocks laid on t h e i r s i d e s , 2 in t h e f i r s t c o u r s e , and 2 in the eighth c o u r s e of t h e s h e l t e r wall, e a c h block with two 4 - by 5-in. c o r e s f o r m e d t h e upper and lower openings for s h e l t e r ventilation. Other s o u r c e s of a i r exchange between t h e s h e l t e r and t h e b a s e m e n t a i r w e r e c r a c k s and i n t e r s t i c e s around the door and in t h e ceiling and walls of the s h e l t e r .

T o evaluate the t i g h t n e s s of the ceiling c o n s t r u c t i o n of t h e s h e l t e r , a s e r i e s of a i r l e a k a g e t e s t s was conducted p r i o r t o t h e

ventilation t e s t s . T h e ceiling c o n s i s t e d of two c o u r s e s of 4-in. c o n c r e t e blocks ( j o i n t s u n m o r t a r e d ) on 1 -in. b o a r d s with flat s i d e s laid on 2 -

by 8-in. wood j o i s t s . With a l l vent openings c o v e r e d and the s h e l t e r door closed and s e a l e d , two c e n t r i f u g a l f a n s w e r e u s e d to p r e s s u r i z e t h e s h e l t e r . T h e a i r flow d e l i v e r e d t o t h e s h e l t e r w a s m e a s u r e d with pitot and s t a t i c p r e s s u r e p r o b e s i n s t a l l e d in t h e fan outlet ducts; t h e

p r e s s u r e developed i n s i d e the s h e l t e r was m e a s u r e d with a m i c r o m a n o m e t e r ( F i g . 4). T o c o m p a r e t h e roof l e a k a g e r a t e with t h a t of t h e ventilation

opening, one opening ( 4 in. by 5 in. ) was uncovered and the a i r leakage t e s t was repeated.

Winter T e s t s

During t e s t s Nos. 1 and 2 of the winter t r i a l s , the door t o t h e s h e l t e r was kept closed to c o n s e r v e h e a t inside the s h e l t e r . T h e two k a t h a r o m e t e r s t o m e a s u r e the ventilation r a t e s of the s h e l t e r and the

basement w e r e placed on a table located centrally in the basement (Fig. 5). T h e helium bottle was placed c l o s e t o t h e outer wall of the s h e l t e r and p l a s t i c tubing was r u n f r o m the valve of the helium bottle into the

s h e l t e r . With this a r r a n g e m e n t helium was r e l e a s e d inside the s h e l t e r for approximately 10 seconds a t 10 p s i p r e s s u r e f r o m outside the

s h e l t e r by manually controlling the valve. T h i s amounted t o 1 t o 2

p e r cent of the volume of the s h e l t e r . Because the t i m e taken to complete the t e s t was approximately 3 _{h r , t h e control box and the}

r e c o r d i n g i n s t r u m e n t s w e r e placed in the kitchen, s o that the o p e r a t o r would not d i s t u r b t h e condition of the basement and the s h e l t e r ( F i g .

6).

During t e s t No. 1 four m e a ~ u r e m e ~ l t s of s h e l t e r ventilation r a t e and t h r e e of the b a s e m e n t w e r e taken. During t e s t No. 2 four m e a s u r e m e n t s of s h e l t e r ventilation r a t e and two of the basement w e r e r e c o r d e d . A

typical helium concentration decay c u r v e for the s h e l t e r and the b a s e m e n t i s shown in Fig. 7 .

Summer T e s t

Ten basement ventilation r a t e m e a s u r e m e n t s w e r e made during t e s t s Nos. 3 _{a n d 4 . The door t o the s h e l t e r was l e f t open. T h e}

basement windows and door to the u p s t a i r s w e r e kept closed. U p s t a i r s d o o r s and windows w e r e allowed t o be opened and closed according t o the n e e d s of the occupants. Nine ventilation r a t e s w e r e r e c o r d e d during the day, with one of the nine r e c o r d e d with the u p s t a i r s doors and

windows closed and locked, and one ventilation r a t e was m e a s u r e d at night.

R e s u l t s and Discussion

The a i r leakage c h a r a c t e r i s t i c of the s h e l t e r ceiling construction i s shown in Fig. 8. It should be noted that p a r t of this i s due to a i r

leakage through the walls and extraneous c r a c k s around t h e s h e l t e r

.

Comparison of t h e a i r leakage r a t e of the ceiling and of the one 4 - by 5-in. ventilation opening a t p r e s s u r e differentials expected under actual

conditions shows t h a t t h e f o r m e r i s about one half of t h a t of the one ventilation opening. T h i s would indicate that the construction of t h e roof i s f a i r l y tight and t h a t the outflow of a i r through the r o o f i s a p p r o x i m a t e l y

10 p e r cent of t h e t o t a l a i r outflow with t h e s h e l t e r under winter conditions. S h e l t e r ventilation r a t e s m e a s u r e d during t e s t s Nos. 1 and

2 a r e shown in T a b l e I . Shelter ventilation i s due t o t h e s t a c k effect c a u s e d by the t e m p e r a t u r e difference between t h e s h e l t e r and the b a s e m e n t a i r ; t e m p e r a t u r e difference v s ventilation r a t e i s plotted in F i g .

9.

During t h e unheated t r i a l s t h e a v e r a g e t e m p e r a t u r e d i f f e r e n c e was 1 3 ° F and the c o r r e s p o n d i n g ventilation r a t e was 4. 1 a i r changes p e r h o u r . During t h e heated t r i a l s t h e a v e r a g e t e m p e r a t u r e difference was 2 6 ° F and t h e ventilation r a t e w a s 7 . 8 a i r changes p e r hour. With t h e s h e l t e r volume of 400 cu f t the a i r f l o w r a t e s a r e 27. 4 and 52. 0 cfm and t h e c o r r e s p o n d i n g Reynolds n u m b e r s f o r the ventilation openings a r e 2100 and 3900 r e s p e c t i v e l y . It would a p p e a r t h a t t h e

a i r f l o w r a t e i s a l m o s t l i n e a r with t e m p e r a t u r e d i f f e r e n c e in t h i s r a n g e of Reynolds n u m b e r . F o r p u r p o s e s of c o m p a r i s o n , a i r f l o w s can be calculated by t r e a t i n g t h e vent h o l e s a s o r i f i c e s . Since t h e flow is

in t h e t r a n s i t i o n region s u b s t a n t i a l difference in t h e values of t h e coefficient of d i s c h a r g e can be expected f o r the two c a s e s . Actual values of the coefficient of d i s c h a r g e , however, a r e lacking. If a

coefficient of d i s c h a r g e of 0. 60 and an exponent of flow of 1/2 a r e taken for both c a s e s the calculated ventilation r a t e s a r e 5. 8 and 8. 1 a i r

changes p e r hour. T h i s might b e r e g a r d e d a s s o m e support for t h e values of ventilation r a t e s obtained e x p e r i m e n t a l l y .

Although t h e s h e l t e r ventilation r a t e s f o r t h e heating t r i a l s w e r e well above 4 a i r changes p e r h o u r , a s d e t e r m i n e d f r o m equation ( 3 ) , i t was not n e c e s s a r y t o apply c o r r e c t i o n s f o r high ventilation r a t e s i n c e t h e a c t u a l r a t e of decay of helium in t h e s h e l t e r was well below that n o r m a l l y r e p r e s e n t i n g 4 a i r changes due t o t h e r e t u r n of helium f r o m t h e b a s e m e n t .

T h e r e s u l t s of t h e b a s e m e n t ventilation m e a s u r e m e n t s f o r both winter and s u m m e r t e s t s a r e given in T a b l e 11. T h e r a t e of a i r change in the b a s e m e n t will affect the amount of f r e s h outdoor a i r brought i n t o t h e s h e l t e r

-

b a s e m e n t a r e a . T h e b a s e m e n t ventilation r a t e is s u b j e c t t o both wind effect and t o t h e s t a c k effect c a u s e d by t h e d i f f e r e n c e s in t e m p e r a t u r e between the outdoor and u p s t a i r s o r b a s e m e n t a i r , and between u p s t a i r s and b a s e m e n t a i r . Considering t h e n u m b e r of v a r i a b l e f a c t o r s t h a t m a y influence t h e ventilation r a t e s , t h e n u m b e r of t e s t s was quite limited. The m i n i m u m ventilation r a t e obtained during the winter t e s t s w a s 0. 24 a i r change p e r hour. In

r a t e p e r hour. With a b a s e m e n t volume of 5800 cu f t , t h e s e r a t e s give a i r f l o w s of 24 to 48 cfm, which a r e l e s s than t h e a i r f l o w in a heated s h e l t e r .

T h e b a s e m e n t ventilation r a t e s obtained during the s u m m e r t e s t s w e r e s u b s t a n t i a l l y lower than t h o s e obtained during t h e winter t e s t s . Both t h e o u t s i d e - t o - b a s e m e n t t e m p e r a t u r e difference and the p r e v a i l i n g wind velocity w e r e lower during the s u m m e r months. The m i n i m u m a i r change r a t e r e c o r d e d was 0. 11 a i r change p e r h o u r . In

Fig. 10 t h e a i r t e m p e r a t u r e s of outdoor, u p s t a i r s and b a s e m e n t a r e plotted a g a i n s t t i m e , together with the ventilation r a t e r e a d i n g

m e a s u r e d during t h e day. As c a n b e s e e n f r o m t h e g r a p h , outside a i r t e m p e r a t u r e i s higher during the day than the b a s e m e n t a i r t e m p e r -

a t u r e and, c o n v e r s e l y , t h e o u t s i d e a i r t e m p e r a t u r e i s lower t h a n t h e b a s e m e n t a i r t e m p e r a t u r e a t night - t i m e . T h e c r o s s -over t a k e s p l a c e a t 6. 00 t o 10. 00 a . m . and again at 6 . 0 0 t o 10.00 p . m . when the t e m p e r a t u r e difference between t h e basem'ent and o u t s i d e a i r i s z e r o . On a c a l m day the ventilation r a t e can b e expected t o b e negligible during t h e s e p e r i o d s . One ventilation r a t e r e a d i n g taken a t night indicated t h a t the ventilation r a t e i s higher c o m p a r e d t o t h e d a y t i m e ventilation r a t e under s i m i l a r conditions, p r o b a b l y due t o t h e r e v e r s a l of a i r flow t h r o u g h the b a s e m e n t . One ventilation r a t e r e c o r d e d with t h e u p s t a i r s d o o r s and windows closed and locked

s e e m s t o indicate that the ventilation r a t e i s s u b s t a n t i a l l y the s a m e whether t h e d o o r s and windows a r e left open o r closed.

S u m m a r y

T h e ventilation t e s t s gave an indication of t h e ventilation r a t e t h a t c a n b e expected in t h e fallout s h e l t e r and t h e b a s e m e n t of a t y p i c a l s m a l l house. The b a s e m e n t ventilation r a t e a p p e a r s t o b e

higher during t h e winter than in t h e s u m m e r due t o t h e higher p r e v a i l i n g wind and the g r e a t e r t e m p e r a t u r e difference between the o u t d o o r s and b a s e m e n t a i r t e m p e r a t u r e s . T h e winter t e s t s showed t h a t the a i r flow into the b a s e m e n t f r o m outdoors m a y b e lower than t h e a i r flow into t h e heated s h e l t e r , t h a t i s , t h e amount of f r e s h a i r brought into the

s h e l t e r m a y be r e s t r i c t e d by the b a s e m e n t ventilation r a t e . T h e s u m m e r t e s t s indicated t h a t , due t o t h e t e m p e r a t u r e i n v e r s i o n of t h e b a s e m e n t and outdoor a i r , t h e r e m a y be p e r i o d s of negligible a m o u n t s of v e n t i - lation on a c a l m day.

Acknowledgments

a s s i s t a n c e in s e t t i n g up i n s t r u m e n t a t i o n and in c a r r y i n g out t h e t e s t s . T h e author a l s o acknowledges t h e guidance given t o t h i s p r o j e c t by M r . A. G. Wilson and Dr. N. B. Hutcheon.

R e f e r e n c e s

( I ) Kent, A. D. and N. B. Hutcheon. Basement fallout s h e l t e r c l i m a t e s t u d i e s . National R e s e a r c h Council, Division of Building R e s e a r c h , I n t e r n a l R e p o r t No. 243, Ottawa, 1962.

( 2 ) Coblenz, C. W. and P. R . Achenbach. Design and p e r f o r m a n c e of a p o r t a b l e infiltration m e t e r . T r a n s a c t i o n s , A m e r . Soc. of Heating and A i r -Conditioning E n g i n e e r s , Vol. 63,

1957, p. 477-482.

( 3 ) T a m u r a , G. T . P e r f o r m a n c e of k a t h a r o m e t e r for i n f i l t r a t i o n m e a s u r e m e n t s . ( T o be i s s u e d a s a n I n t e r n a l R e p o r t of the Division of Building R e s e a r c h , NRC. )

TABLE I

SHELTER VENTILATION RATES DURING WINTER TESTS

Date Shelter B a s em ent T e m p Ventilation R a t e , A i r T e m p , A i r T e m p , Diff, Air change/hr

"F "F O F

T e s t No. 1 ( W i n t e r )

12. 1 . 6 1

T e s t No. 2 ( W i n t e r )

TABLE I 1

BASEMENT VENTILATION RATES DURING WINTER AND SUMMER TESTS ,

Date B a s e m e n t U p s t a i r s Outside Wind Ventilation R a t e , A i r T e m p , Air T e m p , A i r T e m p , mph A i r change/hr O F O F O F (HT G) T e s t No. 1 ( W i n t e r ) T e s t No. 2 ( W i n t e r ) 23. 2 . 6 1 49 46 2 9 13 E . 2 4 28. 2. 6 1 5 1 49 35 12 W . 3 7 T e s t No. 3 ( S u m m e r ) 20. 7 . 6 1 76 86 86 2 SE

.

16 21. 7.61 75 77 8 3 3 SW .ll 24. 7. 6 1 76 7 9 8 4 5 SW . 2 2 25. 7 . 6 1 7 6 77 82 2 SW .ll 25. 7 . 6 1 76 75 7 0 1 W . 1 7 26. 7 . 6 1 76 80 8 1 5 NW . 2 1 T e s t No. 4 ( s u m m e r ) 29.8.61 7 4 75 75 5 W . 1 7 3 0 . 8 . 6 1 76 7 2 7 9 1 W - 1 2 1 . 9 . 6 1 7 7 83 85 3 S

.

16 6 . 9 . 6 1 76 7 5 72 5 E . 3 2

SENSING

THERMISTOR

_STANDARD

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K A T H A R O M E T E R C I R C U I T DIAGRAM

h

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U N D E R A C T U A L S H E L T E R CONDITION

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TEST No. I (UNHEATED TRIALS)

TEST No.

2 (HEATED TRIALS)

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SHELTER

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BASEMENT TEMPERATURE DIFFERENCE, OF

FIGURE 9

SHELTER VENTILATION RATE

l l o 100 L L

d

_{9 0} oz 3 I- a a w 8 0 a I W I- 7 0 6 0 1 2 2 4 6 8 1 0 1 2 2 4 6 8 1 0 1 2 2 4 6 8 1 0 1 2 2 4 6 8 1 0 1 2

MIDNIGHT JULY 2 4 1961 MIDNIGHT JULY 2 5 1961 M l D N IGHT

1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 I

-21 AIR CHANGE PER HOUR

- WIND 5 M.F? H. N.W. E N D OF S H E L T E R -

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UPSTAIRS WINDOWS

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I I I I I I I I I I I I I I I I I I I I I I I I 1 1 1 1 1 1 1 1 1 1 1 -

- 2 2 A I R CHANGE PER HOUR WIND 5 M.F?H. S.W.

1 2 2 4 6 8 1 0 1 2 2 4 6 8 1 0 1 2 2 4 6 8 1 0 1 2 2 4 6 8 1 0 1 2 M I D N I G H T JULY 2 6 1961 M I D N I G H T J U L Y 2 7 1961 MIDNIGHT

1 1 1 1 l 1 1 1 1 1 1 1

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II AIR CHANGE PER HOUR WIND 2 M.F?H. S.W.

FIGURE 10 BASEMENT VENTILATION CONDITIONS TEST NO. 3 ( S U M M E R ) - -

.

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