Measurement of combustion products from a gas cooking stove in a two-storey house

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Measurement of combustion products from a gas cooking stove in a

two-storey house

Goto, Y.; Tamura, G. T.

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no. 12k2

Natlonal

Research

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MEASUREMENT OF COMBUSTION PRODUCTS FROM A

GAS COOKING STOVE IN A TWO-STOREY HOUSE,

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by Yawo Goto and G.T. Tamura

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7 s - 2 Resented at the

77th Annual Meeting of the Air Pollution Control Association

San Francisco, California, June 24

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29,1984. 84

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32.5 (13p.)

printed with permission

DBR Paper No. 1242 Division of Building Research

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ABSTRACT

Tests carried out in a two-storey energy-efficient test house

to determine the relation between air contaminant levels from

gas stove operation and air infiltration rate are reported.

Also, tests conducted with the range hood operating at various

exhaust rates are reported. The calculated diurnal profile of

CO generated from a typical cooking schedule indicated that

progressive build-up of combustion proiductd can occur at low

house air infiltration rate.

Des essais ont 6t6 effectuSs dans une maison experimentale de

deux Stages

a

faible consommation d'gnergie, en vue de

determiner la relation entre la concentration des polluants

dans l'air Bmis

_{B la suite de l'utilisation d'une cuisinisre B}

gaz et le taux d'infiltration d'air.

De plus, on a effectue

des essais en utilisant une hotte qui gvacuait l'air selon

divers d6'

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lors de

l'utilj

vait y

avoir

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MEASUREMENT OF COMBUSTION

PRODUCTS

FROM A

GAS

COOKING

STOVE

IN A

TWO-STOREY

HOUSE

For Presentation at the 77th Annual Meeting of the

Air Pollution Control Association

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Introduction

Products of combustion from fossil fuel fired heating and cooking appliances, particularly those that are unvented to outside, can

contaminate indoor air. The trend towards construction of tighter houses to conserve energy has only made matters worse, for less infiltration air is available to dilute indoor air contaminants.

To investigate the effect of one such type of appliance, tests were conducted in Ottawa during the winter of 1982183 in an energy-efficient two-storey test house with a gas cooking stove in the kitchen. Products of combustion, NO, NO2, CO, and Cop. were measured in the kitchen, living room and bedroom in order to relate the influence of air infiltration and kitchen hood exhaust operation to the levels of air contaminants. Tests were also conducted, using the enclosed kitchen as a test chamber, to establish the values of emission rate for CO, NO and NO2 and of reactivity for NO and NO2.

General Equation for Indoor Air Pollution

The concentration of indoor air contaminants can be described by the following equation developed by Alonzo et al.

,'

assuming uniform mixing:

where

C = indoor contaminant concentration (ppm or a/m3) Co = outdoor contaminant concentration (ppm or ug/m3)

P = fraction of outdoor contaminant level that enters the house through the building air envelope (unitless)

a = air exchange rate in air changes per hour (h-l)

S = indoor contaminant source strength (mL/h or alh)

V

= volume (m3)

k = keactivity, net rate of removal processes other than air exchange I

(h-1).

I Assuming Co, P, a, S and k to be constant over the time period of interest.

Eq. (1) can be solved for C(t) to give: ₄

If

the source is removed at t = 0, i.e..

S

= 0, and Co = 0, the air \ contaminant decays exponentially from the peak concentration. Cp, _I

according to

_I

C(t) = C e-(a + k)t

P (3)

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T e s t Method

The t e s t house I s a two-storey wood frame house w i t h a f u l l basement; f l o o r a r e a 1s 118 m2 and volume, i n c l u d i n g basement, i s 386 m3. The house i s heated with a c e n t r a l warm a i r e l e c t r i c a l h e a t i n g system.

Figure 1 shows t h e p l a n s f o r t h e f i r s t and second f l o o r s , t h e l o c a t i o n of t h e g a s cooking s t o v e i n t h e k i t c h e n , and t h e g a s sampling p o i n t s l o c a t e d 1.6 m above t h e f l o o r i n t h e k i t c h e n , l i v i n g room, and two bedrooms. The g a s s t o v e , w i t h f o u r t o p b u r n e r s and a n oven, was purchased from a nearby department s t o r e , connected t o t h e underground n a t u r a l g a s l i n e , and tuned by a serviceman of t h e l o c a l g a s u t i l i t y . A mass flow meter was i n s t a l l e d i n t h e gas l i n e and c a l i b r a t e d using t h e soap f i l m technique.

NO and NO were measured w i t h a chemilumineacent a n a l y s e r , and CO and C02 w i t h n o n - i i s p e r s i v e i n f r a r e d g a s a n a l y s e r s . The arrangement of t h e v a r i o u s equipment and d a t a a c q u i s i t i o n systems is shown i n Figure 2. A l l

i n s t r u m e n t s f o r g a s a n a l y s i s were checked f o r z e r o and s p a n w i t h a c a l i b r a t i o n gas immediately b e f o r e and a f t e r each t e s t .

Most tests involved o p e r a t i n g the gas s t o v e w i t h one, two, o r t h r e e t o p b u r n e r s covered w i t h w a t e r f i l l e d a l u m i n m p o t s and turned t o meximm s e t t i n g f o r a period of 30 min. A s e p a r a t e t e s t was conducted w i t h t h e

oven s e t a t 17!i°C and o p e r a t e d f o r 2 h. P i l o t l i g h t 8 were on f o r a l l t e a t s . Buildup and decay of contaminants

i n

t h e house were monitored d u r i n g and a f t e r s t o v e operatlon. CO and C02 concentratLons were sampled a t each l o c a t i o n every 1.5 min. Because of t h e time r e q u i r e d f o r measuring both NO and NO2 w i t h o n l y one a n a l y s e r , only the c o n c e n t r a t l o n e i n t h e k i t c h e n were monktored with burners o p e r a t i n g t o permit a s u f f i c i e n t number of readings. A f t e r t h e b u r n e r s were turned o f f , when t h e r a c e of change of c o n c e n t r a t i o n s was m c h l e e s r a p i a . sampling p o i n t s i n t h e k i t c h e n , l i v i n g room, and second bedroom were monitored e v e r y 4.5 min.

The a i r change r a t e of t h e house was measured u s i n g t h e (SF6) t r a c e r gas ,

decay technique, w i t h t h e r e c l r c u l a t i o n a i r f a n of t h e c e n t r a l h e a t l n g system i n o p e r a t i o n s o t h a t t h e r e could be uniform c o n c e n t r a t i o n throughout t h e house. T r a c e r gas (20 mL) was l n j e c t e d upstream of t h e fan i n t o t h e r e t u r n a i r plenum. A f t e r mixing f o r about 30 atln t o achieve a uniform c o n c e n t r a t i o n , gas samples from t h e r e t u r r r a i r plenum were drawn through p l a s t l c cubing t o t h e ion-capture detector/chromatograph. The a i r change r a t e s were c a l c u l a t e d u s i n g Eq.

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w l t h k 0 and t h e measured v a l u e s of

SPg concentration.

Test c o n d i t i o n e a r e emmarlzed i n Table I. T e s t s were conducted

t o

determine t h e l e v e l s of c o n t d n a n t s w l t h s t o v e i n o p e r a t i o n f o r a range of s i r i n f i l t r a t i o n r a t e s . These r a t e s w r e v a r i e d by opening t h e casement windars on t h e f l r e t and second f l w r a , a s required. T e s t s were a l s o conducted t o determine t h e e f f e c t i v e n e s s of t h e k i t c h e n range hood (465 x 755 mm) i n r e d u c i n g contaminant l e v e l . Located 560 mo above the

s t o v e ( s u r f a c e dimension, 600 by 760 mm), It wee cormected t o a length of metal d u c t 100 m i n dlumeter t h a t passed through a plywood panel f i t t e d i n t o the k l t c h e n uLndw. The end of t h e d u c t , j u s t o u t s l d e t h e window, w s a

connected t o a s m a l l centrifugal f a n w i t h a maual damper t o c o n t r o l exhauet r a t e . A c a l i b r a t e d , v e l o c i t y pressure-averaging t u b e t o messure exhaust s a t e was i n s t a l l e d l a t h e s t r a i g h t run o f d u c t . A t e a t was a l s o conducted wlth t h e k i t c h e n wlndw open f o r v e n t i l a t i o n .

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Emission r a t e s were determined f o r CO, NO and NO

.

The k i t c h e n ( c o n t a i n i n g t h e g a s s t o v e ) was converted t o a t e s t chamber 0% 29 m 3 by s e a l i n g t h e f o r c e d - a i r supply and r e t u r n g r i l l s and c o v e r i n g t h e l a r g e openings t o t h e l i v i n g room and hallway w i t h p l a s t i c s h e e t s . Windows and d o o r s o f t h e remainder of t h e house were open and a l a r g e f a n i n t h e l i v i n g room was o p e r a t i n g t o e x h a u s t a i r t o o u t s i d e . I n t h i s way a l l t h e house e x c e p t t h e k i t c h e n was h e a v i l y v e n t i l a t e d t o o u t s i d e t o p r e v e n t combustion p r o d u c t s from r e e n t e r i n g t h e e n c l o s e d k i t c h e n d u r i n g t h e t e s t . A s m a l l f a n i n s i d e t h e k i t c h e n was o p e r a t e d t o promote mixing. Contaminant l e v e l s and a i r change r a t e s were measured d u r i n g and a f t e r b u r n e r o p e r a t i o n . The e m i s s i o n r a t e s were c a l c u l a t e d from measurements made d u r i n g b u r n e r o p e r a t i o n , u s i n g Eq. ( 2 ) t o s o l v e f o r S and d i v i d i n g t h e r e s u l t by t h e f u e l consumption r a t e i n k J / h ; t h e v a l u e s f o r r e a c t i v i t y ( k ) were c a l c u l a t e d , u s i n g Eq. ( 4 ) . from measurements of a i r contaminants w i t h t h e g a s s t o v e o f f and t h e known a i r change r a t e ( a ) from SF6 t r a c e r g a s r e a d i n g s .

R e s u l t s and D i s c u s s i o n

The gas flow r a t e s w i t h one, two and t h r e e t o p b u r n e r s a t maximum s e t t i n g were 0.065, 0.120 and 0.165 L / s , r e s p e c t i v e l y . O u t s i d e c o n c e n t r a t i o n s o f CO v a r i e d from 0.6 t o 1.5 ppm, and of NO2 from 0.01 t o 0.04 ppm. The average h e a t i n g v a l u e f o r n a t u r a l g a s (from monthly measurements r e p o r t e d by t h e l o c a l g a s u t i l i t y ) was 37.3 kJ/L.

CO, Cop, NO, and NO l e v e l s w i t h t h e t h r e e t o p b u r n e r s o p e r a t i n g a t maximum s e t t i n g f o r 30 min t ~ e s t No. 7 ) a r e shown i n F i g u r e s 3a and 3b. The f u r n a c e f a n was o f f , and t h e measured a i r change r a t e was 0.18 ach. When t h e b u r n e r s were t u r n e d on, t h e l e v e l s o f combustion p r o d u c t s i n c r e a s e d r a p i d l y i n t h e k i t c h e n , l i v i n g room and bedroom; when t h e y were t u r n e d o f f , c o n c e n t r a t i o n s decayed slowly owing t o t h e r e l a t i v e l y low a i r change r a t e i n t h e house. The r a t e s of i n c r e a s e i n l e v e l s of CO and C02 were somewhat g r e a t e r i n t h e l i v i n g room t h a n i n t h e k i t c h e n . Maximm l e v e l s of NO2 i n t h e k i t c h e n were, a s expected, h i g h e r w i t h t h r e e b u r n e r s o p e r a t i n g t h a n w i t h only one o r two. The maximum l e v e l s of CO i n t h e k i t c h e n were, however, h i g h e r w i t h one and two b u r n e r s o p e r a t i n g t h a n w i t h t h r e e . T h i s a p p a r e n t anomoly could n o t b e explained. The decay p o r t i o n of t h e c u r v e s i n d i c a t e s t h a t t h e l e v e l s of contamination a r e about t h e same i n t h e t h r e e a r e a s : t h e h i g h e s t c o n c e n t r a t i o n s o c c u r r e d i n t h e bedroom, followed by those i n t h e l i v i n g room and k i t c h e n . Maximum l e v e l s of CO, C02, NO, and NO2 were, r e s p e c t i v e l y , 2.0, 1650, 0.80 and 0.20 ppm.

The r e s u l t s of measurements w i t h t h e oven s e t a t 175OC f o r 2 h ( T e s t No. 18) a r e shown i n F i g u r e 4a f o r CO and

Cop,

and i n F i g u r e 4b f o r NO and NOp. The f u r n a c e f a n was on and t h e a i r change r a t e was 0.12 ach.

Concentrations of CO, Cop, and NO i n c r e a s e d r a p i d l y i n t h e k i t c h e n f o r about 10 min a s t h e temperature of t h e oven approached i t s s e t t i n g , decreased r a p i d l y f o r t h e n e x t 5 t o 10 min, and t h e n i n c r e a s e d s t e a d i l y a g a i n u n t i l t h e oven was t u r n e d o f f . The NOq c o n c e n t r a t i o n i n c r e a s e d r a p i d l y , t h e n r a p i d l y decreased, t h e r e a f t e r remaining e s s e n t i a l l y constant.

Under c o n d i t i o n s of low a i r change r a t e and s i m u l a t e d cooking o p e r a t i o n , F i g u r e s 3a and 4a i n d i c a t e t h a t maxinum l e v e l s of CO and C02 were w e l l below t h e a c c e p t a b l e l i m i t s of 9 ppm and 2500 ppm2, r e s p e c t i v e l y . When a t o p b u r n e r a t maximum s e t t i n g was m a l a d j u s t e d by changing t h e flame from blue t o yellow, CO c o n c e n t r a t i o n i n t h e k i t c h e n i n c r e a s e d from 1.8 t o

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16.0 ppm i n 10 min. F i g u r e s 3b and 4b i n d i c a t e t h a t t h e maximum l e v e l of NO w i t h t h r e e t o p b u r n e r s o p e r a t i n g was l e e s t h a n t h e a c c e p t a b l e l i m i t of 0.33 ppm3. During t h e oven t e s t t h i s l i m i t was exceeded momentarily, j u s t a f t e r t h e oven was t u r n e d on. The maxinun l e v e l of NO was only about 3 p e r c e n t of t h e t h r e s h o l d l i m i t value (TLV) of 25 ppm e s t a b l i s h e d by t h e American Conference of Governmental I n d u s t r i a l H y g i e n i s t s (ACGIH).

Measurements by wade e t al.' on f o u r occupied houses c l e a r l y i a d i c a t e d t h a t l e v e l a of CO. C02, NO and NO2 could be r e l a t e d t o g a s s t o v e ueage. Except f o r one house i n which t h e l e v e l of NO2 exceeded the a c c e p t a b l e l i m i t f o r a

b r i e f p e r i o d , a l l o t h e r measured l e v e l a were h e l m t h e a c c e p t a b l e lid ts. S t u d i e s r e p o r t e d by S t e r l i n g and s t e r l i n g 5 f o r n i n e k i t c h e n s w i t h gas s t o v e e s h m e d t h a t t h e CO l e v e l s a f t e r 2 0 min of c o o k i r y ~ v a r i e d from 29 to

120 ppm, w e l l above t h e a c c e p t a b l e l i m i t . According t o t h e a u t h o r s t h e gas s t o v e s were o p e r a t e d i n k i t c h e n s considered t o b e normel. Macriss and E l k i n s 6 r e p o r t e d measurements of 24-h average NO c o n c e n t r a t i o n s ranging from 0.031 t o 0.052 p p i n t h e k i t c h e n s of f o u r gouses w i t h a i r change r a t e s between 0.20 and 1.0 p e r hour.

E f f e c t s of Air I n f i l t r a t i o n Rate and Range Hood Operation

With t o p burners i n o p e r a t i o n . t h e e f f e c t of a i r change r a t e s on t h e maxi- l e v e l s of CO and NO2 a r e shown i n F i g u r e s 5a and 5b, r e s p e c t i v e l y . An i n c r e a s e i n a i r i n f i l t r a t i o n r a t e from about 0.10 t o 0.90 a i r change p e r hour r e s u l t e d i n a r e d u c t i o n i n maxinum l e v e l s of CO and NO2 of about 20 parcent. F i g u r e s 5a and 5b a l s o show e marked r e d u c t i o n i n CO and NO2 w i t h range hood i n o p e r a t i o n ; maxirmm CO and NO Levels were reduced by about 50 p e r c e n t a t an exhaust r a t e of 22 L / s (8.20 a c h ) end t o a

o e g l i d b l e l e v e l a t 9 4 L / s (0.85 ach). Opening t h e k i t c h e n window r e s u l t e d i n n s i g n i f i c a n t r e d u c t i o n i n CO l e v e l s and, t o 8 l e a s e r e x t e n t . i n N O 2 l e v e l s . Table I shovs t h a t For T e s t e No. 15 and 1 7 , o p e r a t i n g t h e range hood and opening t h e k i t c h e n window r e s u l t e d , a s expected, i n a s u b s t a n t i a l

i n c r e a s e i n house a i r change r a t e . F i g u r e s 5a and 5b a l s o show t h a t t h e l e v e l s of CO with t h r e e b u r n e r s o p e r a t i n g without p o t s a r e s u b s t a n t i a l l y lower t h a n t h e y a r e w i t h p o t s , i n d i c a t i n g t h a t cooking u t e n s i l s a f f e c t proper combustion, r e s u l t i n g i n a h i g h e r CO emission r a t e .

Traynor e t r e p o r t e d t h a t t h e r e s u l t s of s i x range hood experiments showed r e d u c t i o n s i n t h e e f f e c t i v e emission r a t e s of CO, C02, and NO2 by 60 t o 87 percent with exhaust r a t e s from 42 t o 113 LIE. Macriss and E l k i n s 6 r e p o r t e d , on t h e o t h e r hand, a r e d u c t i o n i n NO2 l e v e l s f o r t h e e n t i r e house of 40 t o 50 percent w i t h continuous range hood o p e r a t i o n from 33 t o

113 L/a. R a y n o r e t a1. a l s o r e p o r t e d t h a t when house a i r change r a t e was i n c r e a s e d from 0.30 t o 0.83 p e r hour t h e peak CO c o n c e n t r a t i o n was reduced by only 20 p e r c e n t .

I t may be concluded t h a t a n o p e r a t i n g range hood removing combustion p r o d u c t s a t t h e s o u r c e i s more e f f e c t i v e i n c o n t r o l l i n g l e v e l s of indoor contaminants generated by gas cooking t h a n i s a n i n c r e a s e i n overall. v e n t i l a t i o n r a t e .

Emission Rates and R e a c t i v i t i e s

The emission r a t e s f o r CO, NO, and NO2 a r e given i n Table 11. When one burner covered by a w a t e r f i l l e d p o t was o p e r a t e d a t maxinum (8650 W / h ) , t h e measured emission r a t e f o r CO was 87 vg/W. The emission r a t e f o r two

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84-32.5 burners o p e r a t i n g a t low s e t t i n g ( t o t a l of 2400 k J / h ) was 159 ~ g / k J , whereas f o r one burner o p e r a t i n g a t maximm s e t t i n g w i t h o u t a p o t i t was 52 uglkJ. It appears t h a t t h e CO emission r a t e i s h i g h e r i f b u r n e r s a r e operated w i t h p o t s t h a n w i t h o u t , and a t lower r a t h e r t h a n maximm s e t t i n g s . A s shown i n Table 11, t h e emission r a t e s of CO f o r t h e t h r e e c o n d i t i o n s a r e lower t h a n t h o s e r e p o r t e d by t h e Lawrence Berkeley Laboratory (LBL). The emission r a t e of NO, which was o p p o s i t e t h a t of CO, was h i g h e s t a t 20 ug1kJ w i t h one burner a t maximm s e t t i n g w i t h o u t a p o t and l o w e s t a t 8 M / ~ J w i t h two burners and w a t e r - f i l l e d p o t s a t low s e t t i n g . The emission r a t e s of NO2 f o r t h e t h r e e c o n d i t i o n s were about t h e same a t 15

@/kJ

and s i m i l a r t o those r e p o r t e d by LBL.

The r e a c t i v i t y r a t e ia a measure af how quickly t h e p o l l u c e n t d i s a p p e a r s wiehLn a epace by mechglisma o t h e r t h a n d L l u t i o n (i.e. a b s o r p t i o n , adaorption, o x i d a t i o n , e t c ) . The mean NO r e a c t i v i t y r a c e was

0.03

+

0.03 h-' conpared t o -0.004 f: 0.082 h-' detetmlned by LBL*; t h e mean

NO r e a c t i v i t y r a t e was 0.76 t 0.21 h-1 compared t o t h a t of t h e LBL, i.e., 1.19 f 0.67 h-1,

I n F i g u r e s 5a and 5b t h e c a l c u l a t e d peak v a l u e s of CO and N O 2

c o n c e n t r a t i o n s w i t h t h e t h r e e t o p b u r n e r s o p e r a t l n g a t maximm s e t t i n g a r e compared w i t h measured peak v a l u e s i n t h e k i t c h e n . It may be s e e n t h a t t h e c a l c u l a t e d v a l u e s based on t h e assumption of uniform mixing a r e somewhat h i g h e r than t h e measured values. The e f f e c t of i n c r e a s i n g a i r i n f i l t r a t i o n r a t e i s about t h e same f o r b o t h measured and c a l c u l a t e d values.

Buildup of CO w i t h gas s t o v e o p e r a t i o n f o r a weekday, w i t h a i r change r a t e s of 0.2, 0.5 and 1.0 p e r hour, were c a l c u l a t e d ( F i g u r e 6). The cooking l o a d was assumed t o be 31 500 kJ p e r day,6 and i t was apportioned according t o a

t y p i c a l cooking time of 24, 16, and 82 min f o r b r e a k f a s t , lunch, and d i n n e r , r e s p e c t i ~ e l ~ . ~ A c o n s t a n t g a s consumption r a t e of 15 600 k J / h was assumed, and t h e corresponding CO emission r a t e was o b t a i n e d by l i n e a r e x t r a p o l a t i o n from t h e t e s t data. As shown i n F i g u r e 6, a t 1 a c h CO generated by cooking i s d i s s i p a t e d b e f o r e cooking s t a r t s f o r t h e f o l l o w i n g d a l ; whereas, a t 0.50 ach t h e r e i s r e s i d u a l CO b e f o r e lunch and d i n n e r , although i t d i s s i p a t e s o v e r n i g h t , d i s a p p e a r i n g b e f o r e b r e a k f a s t . A t 0.2 ach, which can be expected i n a r e l a t i v e l y a i r t i g h t house, t h e r e i s

r e s i d u a l CO b e f o r e p r e p a r a t i o n of each meal. T h i s c a n accumulate from day t o day. Although t h e peak v a l u e s of a i r contarninants a r e governed mainly by t h e contaminant emission r a t e , t h e i r r a t e s of decay a r e governed mainly by a i r i n f i l t r a t i o n r a t e .

Summary

Measurements of gas s t o v e emissions i n an energy e f f i c i e n t t e s t house i n d i c a t e t h a t :

1. maximum l e v e l s of CO, C02, NO, and NO2 w i t h t h r e e t o p burners on h i g h s e t t i n g f o r

4

h were 2.0, 1650, 0.80 and 0.20 ppm, r e s p e c t i v e l y ; 2. w i t h t h r e e t o p burners o p e r a t i n g , t h e CO, C02 and N O 2 l e v e l s were below

t h e a c c e p t a b l e limits; w i t h oven o p e r a t i n g , only t h e NO2 l e v e l exceeded t h e a c c e p t a b l e l i m i t , and only momentarily when t h e oven was t u r n e d on; and t h e maximm l e v e l of NO, o b t a i n e d w i t h t o p b u r n e r s on, was much l e s s t h a n one t e n t h of t h e TLV of ACGIH;

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3. i n c r e a s i n g t h e house a i r i n f i l t r a t i o n r a t e from 0.1 t o 0.90 a c h r e s u l t e d i n a r e d u c t i o n of only about 20 p e r c e n t f o r CO and NO2 c o n c e n t r a t i o n s i n t h e k i t c h e n ;

4.

o p e r a t i n g t h e range hood a t 22 L / s reduced t h e peak c o n c e n t r a t i o n by about h a l f t h a t o b t a i n e d by n a t u r a l a i r i n f i l t r a t i o n , and t o a n e g l i g i b l e l e v e l a t 94 L/s;

5. t h e c a l c u l a t e d and measured v a l u e s of peak c o n c e n t r a t i o n s a g r e e d reasonably w e l l ; and

6. a i r contaminant l e v e l s between cooking e p i s o d e s were m c h g r e a t e r i n houses w i t h low a i r i n f i l t r a t i o n r a t e s t h a n i n t h o s e w i t h h i g h e r r a t e s .

Acknowledgment

The a u t h o r s acknowledge t h e a s s i s t a n c e of J. Payer i n s e t t i n g u p i n s t r u m e n t a t i o n and p r o c e s s i n g t h e t e s t readings. T h i s paper i s a c o n t r i b u t i o n from t h e M v i s i o n of Building Research, National Research Council of Canada, and i s published w i t h t h e a p p r o v a l o f t h e D i r e c t o r of t h e Division.

References

1. J . Alonzo, B.L. Cohen, H. Rudolph. H.J. Jow and J.O. E'rohliger, " I n d o o ~ o u t d o o r r e l a t i o n s h i ~ s f o r a i r b o r n e m a t t e r of outdoor orinin." Atmospheric Environment,

13;

55 (1979).

-

2. ASHW Standard 62-1981. V e n t i l a t i o n f o r Accentable Indoor A i r Quality.

3. U.S. Environmental P r o t e c t i o n Agency. A i r q u a l i t y standard. 4. W.A. Wade, 111, W.A. Cote, and J.E. Yocom. "A s t u d y of indoor a i r

q u a l i t y . " J o u r n a l of t h e Air P o l l u t i o n Control Association, 5 ( 9 ) : 9 3 3 (September 1975).

5. T.D. S t e r l i n g and E. S t e r l i n g . "Carbon monoxide l e v e l s i n k i t c h e n s and homes w i t h gas cookers." ~ o i r n a l of t h e Air P o l l u t i o n Control

Association, 29<3):238 (March 1979).

6. R.A. Macriss and R.H. Elkins. "Control of t h e l e v e l of N O i n t h e _X indoor environment." Proc. Fourth I n t e r n a t i o n a l Clean Air Congress, Tokyo, Japan, 1977.

-

7. G.W. Traynor, M.G. Apte, J.F. M l l w o r t h , C.D. Hollowell, and E.M. S t e r l i n g , "The e f f e c t s of v e n t i l a t i o n on r e s i d e n t i a l a i r p o l l u t i o n due t o e m i s s i o n s from a gas-f i r e d range." mvironmental I n C e r n a t i o n a l , A J o u r n a l of Science, Technology, Health Monitoring and

Policy, 8, 447, 1982.

8. G.W. Traynor. D.W. Anthon and C.D. Rollowell. "Techniaue f o r

determining p o l l u t a n t emissions from a g a s - f i r e d range." Atmospheric Environment, 3 1 2 ) . 2979 (1982).

9. T.D. S t e r l i n g and D. Kobayaski, "Use of g a s r a n g e s f o r cookingaand h e a t i n g i n urban dwellings." h u c n a l of t h e Air P o l l u t i o n Contra1 A s s o c i a t i o n , 31(2). 162 (February 1981).

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T a b l e I T e s t c o n d i t i o n s

Range A i r Change T e s t No. of Hood Furnace R a t e

No. B u r n e r s L/s Fan 1 /h Cormeent s

17 3 18 Oven Off On Off On Off On Off On Off On Off On Off Off Off On Off On Off On 22.6 On 22.6 Off 44.8 On 94.4 On 40.1 On Off On Off Off Off On 0.11 0.11 0.17 0.20 0.09 0.17 0.18 0.27 0.53 0.88 0.26 0.26 0.46 0.85 0.41 (0.25)* 0.25 No p o t o n b u r n e r s 0.60 (0.17)* Window open 0.12 Note

-

1. B u r n e r s w i t h w a t e r - f i l l e d p o t s o p e r a t e d a t maximum s e t t i n g f o r 30 min 2. Oven o p e r a t e d a t a s e t t i n g o f 17S°C f o r 120 min 3 .

*

A i r change r a t e measured b e f o r e t e s t T a b l e I1 Contaminant e m i s s i o n r a t e s from t o p b u r n e r s

( x t k J )

N a t i o n a l Research Council

of Canada Lawrence Berkeley L a b o r a t o r y

A* B**

c***

Mean+ Range No. o f Runs

- - - - - - - -

*

One b u r n e r w i t h a w a t e r - f i l l e d p o t o p e r a t e d a t maximum s e t t i n g f o r 1 1 min

**

Two b u r n e r s w i t h w a t e r f i l l e d p o t s o p e r a t e d a t low s e t t i n g f o r 21 min

***

One b u r n e r w i t h o u t a p o t o p e r a t e d a t maximum s e t t i n g f o r 9 min + Two b u r n e r s o p e r a t e d f o r 1 6 min

++ Assuming a v o l u m e t r i c NO2 t o NO r a t i o o f 1. Measurements v a r i e d from

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GA 5

5TQVE ,GAS S A M P L I N G L O C A T I O N S -

G R O U N D F L O O R P L A N S E C O N D FLOOR P L A N

Figure 1 Floor plan of test house

-CALIBRATION GAS KITCHEN LIVING ROOM UST 8EDROOM US1 ACOtliSlTlON SYSTEM Figure 2 Instrumentation 9

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1200

mw TEST NO. 7

FURNACE FAN OFF ' C Z Y 3 u Z 0 2 0 u 1 0

1

1 I 1 I I 4 I 0 20 4 0 60 80 100 120 140 160 T I M E . m i n Figure 3(a)

CO and Cop concentrations vs time, three top burners on for 30 min

0 KITCHEN

0.7 a LIVING ROOM

TEST NO. 7

BURNERS ON MAXIMUM SETTING AIR CHANGElh ' 0.18 FURNACE FAN OFF

T I M E , m i n

Figure 3(b)

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1600

-

1400

-

TEST NO. 18 0 l ' l 1 l l ' ' 1 l 1 1 1 l 0 0 20 40 M) 80 100 120 14) 160 180 20o

zzo

240 260 TIME, m i n Figure 4(a)

CO and C02 concentrations vs time, oven on for 2 h

OVEN SEllING AT 175°C AIR CHANGElh

-

0.12 FURNACE FAN ON 0 20 4) M) 80 100 120 140 160 1BD 200 220 240 260 TIME, m i n Figure 4(b)

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0 KITCHEN

a LIVING ROOM

-

0 BEDROOM

I U r l RANGE HOOD OPERATION

-

1

Z CALCUlAfED VALUES USING EQ. 121

2

-.-

--.la

- . - . - . -

5

X

5 0 _{(45 Llrl} 1V4 Us1

AIR INFILTRATION RATE. ach

F i g u r e 5 ( a ) Maximum CO c o n c e n t r a t i o n v s house a i r i n f i l t r a t i o n r a t e t h r e e t o p b u r n e r s on f o r 30 min 0 . 2 5 I I 1 I I n m 0 KITCHEN

I

Z o

-

2

0.20

=

+ A I R I N F I L T R A T I O N R A T E , a c h v LIVING ROOM

ILlsl RANGE HOOD OPERATION

-

\

-

X a H F i g u r e 5 ( b ) Maximum N O p c o n c e n t r a t i o n v s house a i r i n f i l t r a t i o n r a t e , t h r e e t o p b u r n e r s on f o r 30 min Z ,u

+---/cn~cuur~o VALUES US ING EQ. (21

U Z 0 . 1 5 2 NO POTS VI U Z

-

0 . 0 5

-

3 5 g I94 ust 0 t I 1 I 1 0 0. 2 0.4 0 . 6 0 . 8 1.0 1 . 2

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4 . 5 WlCAL WEEKDAY W\I STGVE OFERATION

A

TIME. h

Figure 6

Calculated diurnal CO concentration profile with house air infiltration rate