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Problems with urea-formaldehyde foam insulation
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PROBLEMS WITH UREA-FORMALDEHYDE FOAM INSULATIONAuthor
C a r l 8. Crawford and C.J. S h i r t l i f f eOrganization/Enterprise
D i v i s i o n of B u i l d i n g R e s e a r c h , N a t i o n a l R e s e a r c h C o u n c i l CanadaKey words
Energy i n B u i l d i n g s . I n s u l a t i o n . Urea formaldehyde foamSummary
The u r g e n t need t o c o n s e r v e e n e r g y i n b u i l d i n g s h a s i n c r e a s e d t h e u s e of non-conventional i n s u l a t i n g m a t e r i a l s s u c h a s u r e a formaldehyde foam i n s u l a t i o n ( W F I ) i n Canadian b u i l d i n g s . Although UPPI i s n o t a p a r t i c u l a r l y good i n s u l a t i n g m a t e r i a l b e c a u s e of i t s h i g h i n i t i a l w a t e r c o n t e n t and t h e r e f o r e i t s h i g h v o l u m e t r i c s h r i n k a g e and known d e t e r i o r a t i o n w i t h a g e , i t was i n s t a l l e d i n more t h a n 80 000 Canadian homes b e f o r e December 1980 when i t s
u s e was banned u n d e r t h e Hazardous P r o d u c t s Act. The ban was b a s e d o n a n i n v e s t i g a t i o n by a n E x p e r t Advisory Committee s e t up by t h e Department of H e a l t h and W e l f a r e Canada. Subsequent s t u d i e s i n t h e l a b o r a t o r y and i n t h e f i e l d have i n d i c a t e d t h a t g a s e s a n d / o r p a r t i c u l a t e s g i v e n o f f by UPPI c a u s e i l l n e s s i n eolae people. The n a t u r e of t h e problem and some of t h e s t u d i e s c a r r i e d o u t i n Canada t o improve u n d e r s t a n d i n g and d e v e l o p methods of r e d u c i n g e x p o s u r e t o t h e s u b s t a n c e s g i v e n o f f by UPPI a r e d e s c r i b e d .
Titre du texte
LA MOUSSED'UR~E-FORMALDEHYDE
ET SES PROBL~MESAuteur
C a r l B. Crawford e t C.J. S h i r t l i f f eOrganisation/Entrepcise
D i v i s i o n d e s r e c h e r c h e s en bat iment.
C o n s e i l n a t i o n a l de r e c h e r c h e s Canadak t s - ~ ( &
d n e r g i e dans l e s b a t i m e n t s , i s o l a t i o n , mousse d'ur6e-formaldbhydeSommaire
Le beaoin u r g e n t de c o n s e r v e r 1 ' 6 n e r g i e dans l e s b l t i m e n t s au Canada a entrafnC une consommation a c c r u e de matCriaux d ' i s o l a t i o n nouveaux comme l a mousse d'ur6e-fomald€hyde (HIUP). Bien que c e t t e mousse ne s o i t pas un e x c e l l e n t matgriau d ' i a o l a t i o n
B
cause de s a f o r t e t e n e u r i n i t i a l e e n e a u occasionnant un i m p o r t a n t r e t r a l t e t q u ' e l l e s e d 6 t ' e r i o r e e n v i e i l l i s a a n t . e l l e a 6tC u t i l i s C e dans p l u s de 80 000 maisons canadiennes juaqu'en decembre1980, d a t e
B
l a q u e l l e s o n usage a CtC i n t e r d i t p a r l a Lo1 s u r l e s p r o d u i t a dangereux. L ' i n t e r d i c t i o n e s t survenueB
l a s u i t e d'une enqudte e f f e c t u e e p a r un c o n i t 6 d ' e x p e r t s f o r d p a r l e m i n i s t e r e de l a SantO e t du Bien-&re. Des e t u d e s u l t e r i e u r e s en l a b o r a t o i r e e t i n - s i t u o n t indiquC que l e e gae e t / o u l e s p a r t i c u l e s (misea p a r l a MIUF provoquaient d e s maladies chez c e r t a i n e spersonnea. Dana c e t t e n o t e , on prCsente l e probl2me e t on d C c r i t l e e Ctudea e n t r e p r i s e a au Canada pour a d l i o r e r l a connaiseance d e s s u b s t a n c e s q u i s e degagent de l a MIUF e t pour Claborer d e s mgthodes a f i n de r e d u i r e l e s r i s q u e s d ' e x p o s i t i o n
B
cea substances.519
PROBLEMS WITH UREA-FORMALDEHYDE FOAM INSULATION
C.B. Crawford and C.J. S h i r t l i f f e , Canada
Urea Formaldehyde Foam I n s u l a t i o n (UFFI) had been i n a t a l l e d i n an e s t i m a t e d 8 0 000 Canadian homes, moatly wood-frame, b e f o r e i t was banned under t h e Hazardous Products Act i n December 1980. The ban was based on t h e advice of a n Expert Advisory Committee s e t up by t h e Department of H e a l t h and Welfare Canada. A y e a r l a t e r , i n December 1981. t h e Canadian Government announced a $110 m i l l i o n a s s i s t a n c e program f o r UFFI honecwners t o cover f r e e t e s t i n g , t e c h n i c a l a d v i c e , and up t o $5000 t a x - f r e e a s s i s t a n c e f o r removal of t h e foam o r o t h e r remedial a c t i o n . L a t e r , a d d i t i o n a l funds were made a v a i l a b l e t o low income f a m i l i e s .
WHAT I S UFFI
Urea Formaldehyde Foam I n s u l a t i o n i s a t h e r m o s e t t i n g o r g a n i c polymer
manufactured a t t h e job s i t e by mixing u r e a formaldehyde r e s i n w i t h a foaming a g e n t c o n t a i n i n g a n a c i d c a t a l y s t and a p r o p e l l a n t such a s colspreased a i r o r n i t r o g e n . The f r e s h foam, having a c o n s i s t e n c y of shaving cream, s e t s w i t h i n a f e u seconds t o a semi-rigid foam w i t h a n i n i t i a l wet d e n s i t y of 40 t o 48 kg/m3. Over a p e r i o d of weeks t o y e a r s i t d r i e s t o a ahrunken, open-celled. f r i a b l e , e t m c t u r a l l y weak m a t e r i a l having a dry d e n s i t y of 9.5 t o 13 kg/m3.
The most a t t r a c t i v e f e a t u r e c l a i n e d f o r UFFI was t h a t i t could be i n s t a l l e d i n an e x i s t i n g w a l l c a v i t y a t high r a t e s through a small hole. The q u a l i t y of t h e t e a s was u n f o r t u n a t e l y highly dependent on t h e i n s t a l l e r , who seldom had any understanding of t h e procesa. Once i n s t a l l e d , t h e foam d e t e r i o r a t e s a t a r a t e depending on t h e f o r a u l a t i o n , t h e a b s o l u t e humidity, and t h e temperature i n t h e w a l l c a v i t y . I n t h e worst c a s e i t can end up a s a powder a t t h e bottom of t h e s t u d space a f t e r a few months. b u t l i t t l e i n f o r m a t i o n i s a v a i l a b l e on t h e average time it t a k e s t o reach t h i s c o n d i t i o n . While crumbling, t h e p a r t i c u l a t e m a t e r i a l c a n be c a r r i e d from t h e c a v i t y i n a i r c u r r e n t s .
Exceasive d r y i n g time i n t h e w a l l c a v i t y can a l s o l e a d t o f u n g a l growth i n t h e foam and on t h e s u r f a c e s of surrounding m a t e r i a l s . C a p i l l a r y a c t i o n may a l s o cause t h e s e s u r f a c e s t o become impregnated w i t h w a t e r , a c i d , and f r a c t i o n s of t h e foam.
DEVELOPMENT OF A STANDARD FOR UFFI
I n 1970 t h e Canadian Government S p e c i f i c a t i o n s Board (nov c a l l e d t h e Canadian General Standards Board, CGSB) was asked t o develop a s t a n d a r d f o r UFPI. A
was e s t a b l i s h e d . b u t f o u r y e a r s l a t e r i t was s t i l l n o t s a t i s f i e d t h a t i t had s u f f i c i e n t knowledge of t h e m a t e r i a l t o p r e p a r e a s t a n d a r d . R e s e r v a t i o n s a b o u t W F I a s a n i n s u l a t o r i n c l u d e d t h e f o l l w i n g (1): d i f f i c u l t y of e n s u r i n g t h a t t h e foam w i l l be p r o p e r l y a p p l i e d , p o s s i b l e c o r r o s i v e n e s s o f UF foam, p o s s i b l e damage caused by w a t e r d u r i n g t h e d r y i n g p e r i o d . p o s a i b l e c o l l a p s e d u e t o v i b r a t i o n s , p o s s i b l e s u s c e p t i b i l i t y t o h y d r o l y s i s . long-term p h y s i c a l s t a b i l i t y , p o s s i b i l i t y of .formaldehyde odour p r o b l e m , t h e r m a l e f f e c t i v e n e s s .
The committee set u p t h r e e working g r o u p s t o a d d r e s s t h e s e p r o b l e m . L i t e r a t u r e d e s c r i b i n g e x p e r i e n c e s i n s e v e r a l o t h e r c o u n t r i e s was reviewed and
i
many w a l l s c o n t a i n i n g UFFI were opened. An e a r l y c o n c l u s i o n was t h a t t h e t h e r m a l r e s i s t a n c e of t h e foam is g r e a t l y reduced by s h r i n k a g e . Although l i n e a r s h r i n k a g e was r e p o r t e d t o v a r y w i d e l y and u n c o n t r o l l a b l y , "it was d e c i d e d t o a c c e p t a n e f f e c t i v e t h e r m a l r e s i s t a n c e of 60 p e r c e n t of t h e t h e r m a l
~
r e s i s t a n c e v a l u e s measured o n t h e guarded h o t p l a t e o r h e a t f l o w m e t e r , assuming t h a t UP foams would s t a b i l i z e a t a l i n e a r s h r i n k a g e of7 p e r c e n t " (1).
~
Another i m p o r t a n t f i n d i n g , r e s u l t i n g from o p e n i n g of w a l l s , was t h a t t h e foam seldom f i l l e d t h e s p a c e t o be i n s u l a t e d . The committee d e c i d e d , t h e r e f o r e , t o w r i t e two s t a n d a r d s : one g o v e r n i n g t h e performancec h a r a c t e r i s t i c s of t h e p r o d u c t when a p p l i e d c o r r e c t l y , and a second d e s c r i b i n g
I
how t h e foam s h o u l d be i n s t a l l e d . A p r o v i s i o n a l p r o d u c t s t a n d a r d was i s s u e d i n May 1977, and i n Decembere 1977 CGSB 51-GP-24M, "Thermal I n s u l a t i o n , Urea Based, Foamed I n - s i t u , " was p u b l i s h e d . During 1977 t h e m a n u f a c t u r e r s improved t h e i r t r a i n i n g c o u r s e s f o r a p p l i c a t o r s and i n December 1977 a p r o v i s i o n a l s t a n d a r d f o r t h e i n s t a l l a t i o n of UFFI was i s s u e d a s CGSB 51-GP-22MP. I n J u l y 1980 CGSB p u b l i s h e d 51-GP-43MP, "Hanual For: I n s t a l l e r s of Urea Formaldehyde Foam Thermal I n s u l a t i o n . "B o t h t h e product and i n s t a l l a t i o n s t a n d a r d s were u r g e n t l y r e q u i r e d by t h e i n d u s t r y i n o r d e r t o q u a l i f y UFFI under t h e Canadian Home I n s u l a t i o n Program (CHIP). The CHIP program, i n t r o d u c e d by t h e Canadian Government i n
September 1977 a s a means of e n c o u r a g i n g e n e r g y c o n s e r v a t i o n , p r o v i d e d f i n a n c i a l a s s i s t a n c e t o h o o e w n e r s f o r t h e t h e r m a l u p g r a d i n g of o l d e r houses.
1
EMERGENCE OF PROBLEMSThe i n a d e q u a c i e s of t h e foam a s a t h e r m a l i n s u l a t o r began t o f a d e i n s i g n i f i c a n c e when h e a l t h problema a t t r i b u t e d t o formaldehyde g a s i n UFPI- i n s u l a t e d hones emerged. A t t h e r e q u e s t of t h e CGSB c o d t t e e t h e Department
52 1
o f H e a l t h and W e l f a r e a d v i s e d t h a t t h e u p p e r l e v e l of formaldehyde g a s i n homes s h o u l d be s e t a t 0.1 ppm i n t h e CCSB p r o d u c t s t a n d a r d . The i n d u e t r y r e q u e s t e d t h a t t h e l e v e l be s e t a t l e a s t t w i c e a s high. When i t became c l e a r t h a t t h e r e was no way t o p r e d i c t o r c o n t r o l t h e e m i s s i o n s from t h e p r o d u c t and t h e r e s u l t i n g l e v e l s i n b u i l d i n g s , t h e CGSB committee r e f u s e d t o i n c l u d e t h i s i n t h e s t a n d a r d . The Department of H e a l t h and Welfare i n t u r n s u g g e s t e d t h a t u s e of t h e p r o d u c t i n t h e CHIP program be d i s c o n t i n u e d , and e s t a b l i s h e d t h e E x p e r t Advieory Committee t h a t s u b s e q u e n t l y recommended t h e ban.
Once t h e ban was p u b l i c i z e d and a r e p o r t i n g mechanism was e s t a b l i s h e d , many of t h e o c c u p a n t s of UFFZ homes r e p o r t e d i l l n e s s e s of v a r i o u s k i n d s and
-
s u b s e q u e n t l y t h e market v a l u e of U F F I - i n s u l a t e d homes dropped d r a m a t i c a l l y . The i n f l u e n c e of UFFI on h e a l t h was g e n e r a l l y a t t r i b u t e d t o i t s e m i s s i o n of formaldehyde, a l t h o u g h t h e c o n t r i b u t i o n s of o t h e r g a s e s and p a r t i c u l a t e s a r e s t i l l under i n v e s t i g a t i o n . The problem is c o m p l i c a t e d by t h e g r e a t v a r i a t i o n i n hiunan s e n s i t i v i t i e s and by changes i n s e n s i t i v i t y w i t h e x p o s u r e and time ( 2 ) . Symptoms of e x p o s u r e i n c l u d e eye. n a s a l , and r e s p i r a t o r y t r a c t i r r i t a t i o n . s o r e t h r o a t , headache and n o s e b l e e d s . Recovery is g e n e r a l l y r a p i d when e x p o s u r e is t e r m i n a t e d . The n o n - e p e c i f i c n a t u r e of t h e symptoms combined w i t h t h e i m p o s s i b i l i t y of e s t a b l i s h i n g l e v e l s of p r e v i o u s e x p o s u r e r e s u l t i n g from UFFI w h i l e a g i n g under d a i l y and s e a s o n a l m o i s t u r e and wind f l u c t u a t i o n s make i t i m p o s s i b l e t o q u a n t i f y t h e c o n t r i b u t i o n of UFFI t o t h e h e a l t h problem.NATIONAL TESTING SURVEY OF CANADIAN HOMES
A s a consequence o f t h e ban, government a g e n c i e s were d e l u g e d w i t h t e l e p h o n e c a l l s and l e t t e r s from homeowners w o r r i e d a b o u t t h e i r h e a l t h o r t h e market v a l u e of t h e i r hones. I n o r d e r t o d e a l w i t h t h e s e demands t h e Department of Consumer and C o r p o r a t e A f f a i r s Canada e s t a b l i s h e d , i n J u n e 1981, a Urea Formaldehyde Foam I n s u l a t i o n I n f o r m a t i o n and C o o r d i n a t i o n C e n t r e , which was soon r e c e i v i n g up t o 400 t e l e p h o n e i n q u i r i e s a day. S h o r t l y a f t e r w a r d s v t h e C e n t r e launched a c o q r e h e n s i v e n a t i o n a l t e s t i n g s u r v e y t o d e t e r m i n e ambient formaldehyde l e v e l s f o r both i n d o o r and o u t d o o r a i r and t o look f o r any o t h e r f a c t o r s t h a t might be i n f l u e n c i n g h e a l t h p r o b l e m i n t h e a f f e c t e d homes. Formaldehyde l e v e l s were measured i n 2275 hones, i n c l u d i n g ( a ) 378 c o n t r o l h o u s e s w i t h o u t UFFI; ( b ) 100 "problem" UFFI h o u s e s where s e r i o u s h e a l t h problems o r c o n c e r n s had been r e p o r t e d ; ( c ) 651 h o u s e s c h o s e n from UFFI C e n t r e € i l e s ; and ( d ) 1146 h o u s e s s e l e c t e d from CHIP f i l e s . The a v e r a g e o u t d o o r formaldehyde l e v e l s measured o v e r 2 h d u r i n g t h e daytime ranged from 0.007 t o 0.909 ppm. I n g r o u p ( a ) , c o n t r o l h o u s e s , 2.6 p e r c e n t had formaldehyde l e v e l s g r e a t e r t h a n 0.1 ppm, measured o v e r t h e s a n e 2 h a t two l o c a t i o n s . I n
group (b), problem houses, 47 percent exceeded 0.1 ppm, and in (c) and (d) 5.1 and 10.2 percent, respectively. exceeded this level.
Host inside measurements were made over the 2-h period after the home had been closed for 18 h and after occupant-related sources of formaldehyde had been eliminated or reduced. Average levels for the following seven days, without such reductions, were measured at the same locationa in over
750 holses. Large discrepancies were disclosed between 2-h and seven-day measurements for given houses, the average seven-day readings being close to 50 percent higher. An extensive analysis of the results of the survey will be released in early 1983.
REPORT OF HAZARDOUS PRODUCC BOARD OF REVIEW ON UFFI
On 24 April 1981 the Hinieter of Consumer and Corporate Affairs, in accordance with the provisions of the Hazardous Products Act and at the request of one of the distributors of the banned product, authorized a three e m b e r Board of Review on UFFI. The Board held public hearings at seven cities from coast t o
coast between 28 June 1981 and 6 January 1982, at a cost of nearly $2 million.
During the process, one of the most complete collections of scientific and medical information was amassed, analysed and debated by experts fram the U.S. and Canada. On 5 October 1982 the Board submitted its report (3).
The Board was not impressed with thk quality control or with the effectiveness of UFFI as an insulating material. It concluded that "no feasible standard would adequately protect the public from the risk of injury associated with the product, nor would it be feasible to eliminate or reduce the level of formaldehyde off-gassing from the product. The reports. testa and testimonies show us that the urea-formaldehyde foam insulation production and use cannot be adequately controlled or predicted."
The Board quoted the U.S. National Academy of Sciences Committee on
Toxicology as follcwa: "There ie no population threshold for the irritant effects of formaldehyde in humane. Information from controlled human studies and cooplaint-related investigations suggests that, even at extreely low airborne concentrations, a proportion of the population will respond with some irritation."
Sensationalism in the media. the sudden banning of the material without warning, and exaggeration of the health problem by some consumers associations were blamed by the Board for the loee of value of UFFI-insulated houses. Nevertheleea, the Board concluded that the possible risks to health from elrpoaure to UFFI are sufficient t o warrant a continuation of the ban on its use and that it apply to all buildings.
REPORT OF PARLIAMENTARY COMMITTEE ON UFFI
On 26 J u l y 1982 t h e Standing Committee on Health. Welfare and S o c i a l A f f a i r s was a u t h o r i z e d by t h e government t o i n v e s t i g a t e v a r i o u s q u e s t i o n s w i t h r e s p e c t t o UFFI. On t h e b a s i s of testimony by many w i t n e s s e s , w r i t t e n submiesions, and o t h e r i n v e s t i g a t i o n s , i t i s s u e d i t s f i n a l r e p o r t i n December 1982 (4).
The r e p o r t made a number of s u g g e s t i o n s aimed a t reducing t h e r i s k of s i m i l a r problems i n t h e f u t u r e . It a l s o r e c o m n d e d t h a t t h e ban be continued, although i t recognized t h a t " t h e degree of h e a l t h r i s k a s s o c i a t e d w i t h UFFI remains undetermined and s u b j e c t t o a n ongoing d e b a t e w i t h i n t h e h e a l t h f i e l d . "
The Committee advocated a number of a c t i o n s i n c l u d i n g t h e follawing:
-
a comprehensive e p i d e m i o l o g i c a l s t u d y , s i m i l a r t o a p r o p o s a l of t h e World H e a l t h Organization. t o d e t e r m i n e whether t h e r e is any r e l a t i o n between formaldehyde exposure and n a s a l cancer i n humans.-
a comprehensive study of i n d o o r a i r p o l l u t a n t s and t h e i r p o t e n t i a l h e a l t h e f f e c t s ,-
d e v e l o p e n t of a c l e a r and e f f e c t i v e p o l i c y on formaldehyde exposure t o t h e p u b l i c , a i n c e t h i s chemical is e m i t t e d not o n l y by UFFI but ise s s e n t i a l l y u b i q u i t o u s i n t h e environment,
-
i d e n t i f i c a t i o n of o t h e r g a s e s e m i t t e d by UFFI i n o r d e r t o a e a s u r e t h e i r c o n c e n t r a t i o n s and e s t a b l i s h , i f p o s s i b l e , t h e i r e f f e c t s on human h e a l t h ,-
development of more e f f i c i e n t and l e s s expensive methods of removing UFFI from a l l t y p e s of b u i l d i n g s .-
development of a methodology f o r t h e d e t e c t i o n and measurement of formaldehyde and o t h e r gases.WHAT CAN THE HOMEOWNER DO?
Formaldehyde and perhaps o t h e r g a s e s g i v e n o f f by UFFI may cause r e s p i r a t o r y d i f f i c u l t i e s and o t h e r d i a c o o t o r t s . The Board of Review noted t h a t "Removal of t h e i n d i v i d u a l from exposure u s u a l l y r e s u l t s i n a prompt c e s s a t i o n o r remission of symptoms, w h i l e r e t u r n t o exposure r e r u l t s i n t h e r e t u r n of symptom." A s m a l l p r o p o r t i o n of t h e p o p u l a t i o n , perhaps 10 p e r c e n t , is
bothered by very low e o n c e n t r a t i o n a of formaldehyde.
The holleawner must f i r s t be made aware t h a t formaldehyde i s g e n e r a t e d a t Appreciable l e v e l s by many products commonly found i n houses and by many household a c t i v i t i e s . These products and a c t i v i t i e s i n c l u d e some plyvoods. most p a r t i c l e boards. veneer f u r n i t u r e , p a i n t , n o r c a r p e t s , cooking, and c i g a r e t t e smoking. Secondary s o u r c e s a r e c r e a t e d when formaldehyde i s
adsorbed on f a b r i c s , p a i n t e d s u r f a c e s and c a r p e t s w h i l e l e v e l s a r e high, t h e n d e e o a k d when eelaaioncs from primary s o u r c e s decrease. The s o l u t i o n
Le
t oIl
524remove t h e primary s o u r c e s and t o d i s c h a r g e t h e secondary sources. Where t h e primary source is i n w a l l c a v i t i e s , a s with UFFI, p r e s s u r i z i n g t h e l i v i n g s p a c e w i l l prevent c o n t d n a t e d a i r from flowing i n t o i t and thereby remove t h e source. P r e s s u r i z a t i o n should be reduced i n w i n t e r (when t h e dehydrated and discharged foam e m i t s l i t t l e gas) t o prevent condensation i n t h e wall. S e a l i n g l e a k s i n t h e i n n e r a k i n of t h e w a l l w i l l s i m i l a r l y e l i m i n a t e t h e s o u r c e a s w e l l a s t h e p o t e n t i a l f o r p r o b l e m w i t h outward f l w of a i r . Continuous v e n t i l a t i o n reduces peak c o n c e n t r a t i o n s a s w e l l a s average v a l u e s , b u t i t is e f f e c t i v e only i f i t r a p i d l y d e p l e t e s t h e sources. M r c l e a n e r e and s c r u b b e r s cen provide added p r o t e c t i o n , but a s y e t t h e i r performance and e f f e c t on occupants a r e n o t p r e d i c t a b l e .
One way t o remove t h e source from w a l l c a v i t i e s is t o open t h e w a l l s and t a k e o u t t h e UFFI and any contaminated m a t e r i a l a t h a t can be removed. and t o n e u t r a l i z e contaminants i n remaining m a t e r i a l s . Contaminated s u r f a c e s
g e n e r a l l y emit a t l e v e l s s i m i l a r t o thoee of t h e foam, and o f t e n a t g r e a t e r I r a t e s . Contamination of wood products is more s e v e r e t h a n t h a t i n masonry
m a t e r i a l s .
I n A p r i l 1981 t h e National Research Council Canada i s s u e d B u i l d i n g P r a c t i c e Note 19, Urea Formaldehyde Foam I n s u l a t i o n ( 5 ) . t o e x p l a i n what UFFI is, how t o determine whether a problem e x i s t s , and what t o do about i t . I n
August 1981 NRCC i s s u e d Building P r a c t i c e Note 23, Urea Formaldehyde Foam I n s u l a t i o n : Problem I d e n t i f i c a t i o n and Remedial Measures f o r Wood Frame Construction (6). Thie Note assembled and summarized a l l t h e t e c h n i c a l knowledge a v a i l a b l e on t h e UFPI problem i n houses and gave e x t e n s i v e guidance on problem i d e n t i f i c a t i o n and r e o e d i a l and p r e v e n t i v e meaeuree. More than 50 000 c o p i e s of t h i s n o t e have been d i s t r i b u t e d . A companion n o t e d e a l i n g with masonry c o n s t r u c t i o n is expected t o be i s s u e d e a r . 1 ~ i n 1983.
These documents have been used a s a b a s i s f o r t r a i n i n g r a n u a l e f o r
c o n t r a c t o r s and homeowners performing remedial measures. C e r t i f i c a t i o n by t h e UFFI Centre is nav r e q u i r e d f o r C o n t r a c t o r s c a r r y i n g o u t s u b s i d i z e d removal of UFFI, and government i n s p e c t o r s provide advice and monitoring s e r v i c e s t o t h e homeowner. A preliminary survey h a s shown t h a t t h e s e a c t i o n s have g r e a t l y reduced poet-removal h e a l t h complaints, although they do not always reduce f ornaldehyde l e v e l s .
CUURENT ASSESSMENT OF THE PROBLEW
The UFFI problem i a interwoven w i t h f a c t o r s t h a t a r e c a u s i n g t h e " e i d c b u i l d i n g syndrome" now recognized i n t e r n d t i o n a l l y . T h i s syndrome is probably caused by t h e p r o l i f e r a t i o n of source@ of contamination a s w e l l a s d e c r e a s e i n v e n t i l a t i o n r a t e s a r i s i n g from energy c o n s e r v a t i o n e f f o r t s . S e v e r a l p b t i o n a l and i n t e r n a t i o n a l o r g a n i z a t i o n s a r e g i v i n g i t t h e i r a t t e n t i o n . The problem of
a i r q u a l i t y is complex and is a s s o c i a t e d w i t h s u c h t h i n g s a s t o b a c c o smoking. u n v e n t i l a t e d combustion, and v a r i o u s b u i l d i n g m a t e r i a l s and consumer p r o d u c t s t h a t g i v e o f f a v a r i e t y of g a s e s and r e s p i r a b l e suspended p a r t i c u l a t e s .
A m u l t i - d i s c i p l i n a r y t a s k f o r c e of e x p e r t s s e t up w i t h i n NRCC h a s i d e n t i f i e d t h e f o l l o w i n g u r g e n t a r e a s f o r s t u d y of UFFI:
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C h a r a c t e r i z e t h e m a t e r i a l i t a e l f i n o r d e r t o be a b l e t o a s s e s s i t s performance i n s e r v i c e and i t s s t a b i l i t y . and t h u s be a b l e t o a n t i c i p a t e t h e k i n d s of compounds t h a t may be g i v e n o f f a t v a r i o u s t i m e s due t o a g i n g of t h e m a t e r i a l .-
Measure a c c u r a t e l y t h e compounds g i v e n o f f .-
Develop ways of r e d u c i n g e m i s s i o n s o r e x c l u d i n g t h e s e compounds from occupied s p a c e .-
Develop ways of r e d u c i n g t h e c o n c e n t r a t i o n of p r o d u c t s , f o r example, by p r e s s u r i z i n g t h e a p a c e , v e n t i l a t i n g i t , o r c l e a n i n g t h e a i r m e c h a n i c a l l y o r c h e m i c a l l y .-
Develop e f f e c t i v e ways of removing UFFI foam, when n e c e s s a r y , and of n e u t r a l i z i n g t h e s p a c e i t occupied.-
R e l a t e t h e p o t e n t i a l f o r h e a l t h p r o b l e m t o t h e p r e s e n c e of conpounds a s s o c i a t e d w i t h v a r i o u s f o r m u l a t i o n s of UFFI.-
Develop t e c h n i q u e s f o r r e c o n s t r u c t i n g e n e r g y - e f f i c i e n t w a l l s .A l l t h e s e q u e s t i o n s have proved t o be e x t r e m e l y complex and d i f f i c u l t . I t is i m p o s s i b l e , f o r example, t o c o r r e l a t e t h e magnitude of a p a r t i c u l a r problem w i t h i n d i v i d u a l r e a c t i o n because of v a r i a t i o n s i n human s e n s i t i v i t i e s . T h e r e i s g r e a t v a r i a t i o n i n t h e c h a r a c t e r of t h e foam from h o u s e t o house and e v e n w i t h i n a s i n g l e house owing t o t h e m a n i p u l a t i o n of c h e m i c a l q u a n t i t i e s by
i n d i v i d u a l i n s t a l l e r s , m o d i f i c a t i o n s t o t h e f o r m l a t i o n by d i s t r i b u t o r s , and age and u n i f o r m i t y of t h e b a s i c components b e i n g used. The o f f - g a s s i n g of UFFI is a f u n c t i o n of age, s t r u c t u r e , pH, and m o f s t u r e c o n t e n t of t h e fqam, a s a e l l a s a b s o l u t e h u m i d i t y , t e m p e r a t u r e g r a d i e n t s and f l u c t u a t i o n s i n t h e foam, and speed of t h e a i r f l o w i n g through and around i t . I n d i c a t i o n s a r e t h a t s t o r a g e of formaldehyde i n t h e foam c a n be a f u n c t i o n of t h e weather d u r i n g t h e p r e v i o u s s e v e r a l weeks. L e v e l s of c o n c e n t r a t i o n i n o c c u p i e d s p a c e v a r y from hour t o hour and a r e t h e r e f o r e m i s l e a d i n g i f c a r r i e d o u t o v e r a s h o r t p e r i o d of t i m e o r a t a p a r t i c u l a r s e a s o n of t h e y e a r . F i n a l l y , i t i a e x t r e m e l y d i f f i c u l t t o measure minute q u a n t i t i e s of unknown g a s e s ; some well-known measurement t e c h n i q u e s t h a t had b e e n a c c e p t e d v i r t u a l l y a s s t a n d a r d s f o r o c c u p a t i o n a l e x p o s u r e s have been found t o g i v e i n c o r r e c t v a l u e s i n t h e l o v e r ranges.
526
RESEARCH ACTIVITIES
The b a s i c r e s e a r c h e f f o r t needed t o g u i d e a more e x t e n s i v e program i n b e i n g c a r r i e d o u t in-house by t h e N a t i o n a l Research Council Canada. I n a d d i t i o n , a p p r o x i m a t e l y $3 m i l l i o n h a s been s p e n t f o r c o n t r a c t r e s e a r c h u n d e r NRCC guidance. Some 45 c o n t r a c t s a r e c u r r e n t l y under way. The c o n t r a c t r e s e a r c h i n c l u d e s t h e f o l l o w i n g :
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O b s e r v a t i o n s of c i r c u m s t a n c e s i n s p e c i f i c problem h o u s e s and f i e l d m o n i t o r i n g of r e m e d i a l measures.-
Comparison of formaldehyde l e v e l s i n w a l l s p a c e s and a d j a c e n t l i v i n g s p a c e s .-
I d e n t i f i c a t i o n of p a r t i c u l a t e s and g a s e s o t h e r t h a n formaldehyde g i v e n o f f by UFFI.-
I n v e s t i g a t i o n of new g a s d e t e c t i o n t e c h n i q u e s .-
Development of a s e t of d o s i m e t e r s f o r low-cost m o n i t o r i n g o f formaldehyde and o t h e r g a s e s .-
Improved l a b o r a t o r y a n a l y s e s of exposed d o s i m e t e r s and a s s e s s m e n t of t h e r e l i a b i l i t y of t h e r e s u l t s .-
Development of c a l i b r a t i o n f a c i l i t i e s f o r i n s t r u m e n t s and d o s i m e t e r a .-
I n v e s t i g a t i o n of methods of n e u t r a l i z i n g c o n t a m i n a t e d m a t e r i a l s f o l l m i n g UFFI removal.-
L a b o r a t o r y and f i e l d e v a l u a t i o n of e f f e c t i v e n e s s of r e m e d i a l measures.-
I n v e s t i g a t i o n of t h e e f f e c t s of UFFI on t h e s t r u c t u r e and s e r v i c e s i n b u i l d i n g s .-
I n v e s t i g a t i o n of t h e a p p l i c a b i l i t y of a i r f i l t e r s and s c r u b b e r s i n t h e c l e a n i n g of contaminated a i r .-
Development of t e c h n i q u e s t o i d e n t i f y t h e number o f h a z a r d o u s compounds i n e m i s s i o n s and t o c a t e g o r i z e t h e f o r m u l a t i o n s and f i e l d specimens by b i o l o g i c a l damage.Much h a s been a c h i e v e d b o t h in-house and u n d e r c o n t r a c t i n f u r t h e r i n g u n d e r s t a n d i n g of t h e n a t u r e of t h e problem i n i n d i v i d u a l h o u s e s . I n p a r t i c u l a r , t e c h n i q u e * f o r m e a s u r i n g g a s e s g i v e n o f f by UFFI have been e v a l u a t e d , r e l i a b i l i t y and s e n s i t i v i t y have been g r e a t l y improved, and C o a t s have been reduced from s e v e r a l hundred t o a few d o l l a r s f o r e a c h measurement. Under t h e p r e s s u r e of e v e n t s many i n d i v i d u a l s and o r g a n i z a t i o n s i n Canada have d e v e l o p e d e x p e r t i s e t h a t w i l l be u s e f u l i n c a r r y i n g o u t t h e c o r r e c t i v e measures r e q u i r e d f o r t h e f u t u r e .
The UFFI problem h a s drawn a t t e n t i o n t o one a s p e c t of t h e much b r o a d e r problem of a i r q u a l i t y i n b u i l d i n g s . I t h a s i l l u s t r a t e d t h e many u n c e r t a i n t i e s of a s s e s s i n g h e a l t h h a z a r d s on t h e b a s i s of a few s i m p l e measurements of g a s c o n c e n t r a t i o n . F a c t o r s s u c h a s t h e d a i l y p r o f i l e e x p o s u r e , i n c l u d i n g d u r a t i o n of exposure-f ree p e r i o d s , may i n f l u e n c e t h e
527
a b i l i t y of t h e body t o f l u e h o u t c o n t d n a n t s and lower its a u e c e p t i b i l i t y t o
i l l n e s s e s . Extrapolations-from occupational expoeure and r u l e e of thumb
have not been adequate f o r e v a l u a t i n g t h e a c c e p t a b i l i t y of t h e enviro-nt. Several avenuee of research a r e , however, showing eome success.
One technique being a p p l i e d t o UPFI involvee t h e expoeure of a number of aimple b i o l o g i c a l orgeniema t o various concentrations of gaeea. p a r t i c u l a t e s
o r water e x t r a c t s of t h e m a t e r i a l and l e a e u r e r e n t of t h e i r reeponee. The
response t o theee e p e c i f i c mixturee of chemicals i e then compared with the reeponee t o known m a t e r i a l s t o determine unacceptable o r suepect l e v e l e of
expoeure.
Ae
w e l l , t h e i d e n t i f i c a t i o n of t h e more harmful componente i n t h egas and p a r t i c u l a t e emiseione from UFFI i e continuins, and c o q a r i e o n e of foam from "eick" and normal buildinge a r e g i v i n g u e e f u l information.
UFPI i e j u s t one of ram/ modern m a t e r i a l s t h a t emit compounde t o which
i n d i v i d u a l s may r e a c t . The c h a r a c t e r i z a t i o n and t h e i d e n t i f i c a t i o n and
q u a n t i f i c a t i o n of t h e s e compounde a r e e e e e n t i a l i n achieving a e a t i e f a t o r y
environment i n buildinge. Clearly t h i s is a problem of t h e higheet p r i o r i t y
f o r b u i l d i n g reeearch.
REFERENCES
1. DOULES, A.M., and SHIRTLIFFB, C.J. Development of a Canadian Standard f o r
Urea Formaldehyde T h e m 1 Wall I n s u l a t i o n , &Thermal I n e u l a t i o n
Perforaance. American Society f o r T e s t i n g and Materiale, STP 718. 1980.
pp. 361-394;
2. SMALL, B.W. Chemical S u e c e p t i b i l i t y and Urea-Formaldehyde Foam
I n s u l a t i o n . k c o - P l a n Inc. (Box 3000, cornwall, Ont.. Canada K6R 5118).
1982.
3. Report of t h e Haaardoue Product b a r d of Re9inr on Urea Formaldehyde Foam
Innulation. Coneumer and Corporate A f f a i r s Canada, 1982. 127 p.
4.
Report on Urea F o ~ l d e h y d e Foam I n e u l a t i o o of t h e Standing C o r n i t t e e onRealth. Welfare and S o c i a l Affairs. Supply and Servicee Canada,
December 1982.
5. CHW, G.A., BOURN. Rep,, and SRIRTLIPFE, C.J. Urea Formaldehyde Foaa
Innulation. National Reeearch Council Canada, Divinion of Building
Rerearch, Building P r a c t i c e Note 19, A p r i l 1981.
6. M U , R.P., SRIRTLIPFE, C.J., and CBOUN, G.A. Urea Formaldehyde Foam
Insulation: Problem I d e ~ i t i f i c a t i o n and Remedial Ueaeuren f o r Wood-Frame
Conrtruction. National Reeearch Council Canada, Bivieion of Building
