Document 7OEJ9jBNOboVXamnbrBQbqXR6

FILE NAME: WR Grace (WRG) DATE: March 23, 1971 DOC#: WRG226 DOCUMENT DESCRIPTION: 1971 Baltimore County Building Code regarding disapproval of sprayed on fireproofing ;-y rJILD~NG CO*>3 rules :::: reeulaoes (under autroaity of section 10?.2 ) GODS KEviORAirDU NO. 136 'larch 23y 1571 SUBJECT : DISAPPROVAL OF SPEAISD ON FIRE PROOFING KATERIALS for structures built in BaltLnore County for the following reasons: . 1. Incompleteness of cover . 2. Spalling -8 GENTLEMEN - we r e a l i z e t h a t t h i s - e p o r t d e a l s w i t h o n l y one p r o d u c t o f the s e v e r a l whi ch ar e a v a i l a b l e . We can s a y o n l y t h a t we have r evi ewed i t w i t h D r * . Tabershaw and Cooper and we do not f e e l t h a t we a r e c o n t r b u t i n g s i g n i f i c a n t amounts o f a s b e s t o s to the San F r a n c i s c o e n v i r o n me n t . We i nt end to reduce the a l r e a d y low h a z a r d of the d i r e c t l y i n v o l v e d workmen by u s i n g Bureau o f Mines A ppr ov ei R e s p i r a t o r s and reducing n o z z l e v e l o c i t i e s . We a r e c e r t o n l y g o i n g to be more di l i g e n t in c l e a n up and d i s p o s a l p r o c e d u r e s . Beyond t h a t we do not h c n e s l y see t h a t a n y t h i n g can be done to m a t e r i a l l y improve the s i t u a t i o n s h o r t o f a s b e s t o s e l i m i n a t i o n . We ar e w o r k i n g on t h i s and w i l l a c c o m p l i s h i t . We have t r i e d to the b e s t o f our a b i l i t y to g i v e you tr u t h and not f i c t i o n , f a c t s and not s u p p o s i t i o n . If your d e l i b e r a t i o n s i n d i c a t e to you that t h i s product needs f u r t h e r r e g u l a t i o n d u r i n g the i n t e r i m p e r i o d , we w i l l c o o p e r a t e in any way we can to a s s i s t in a r r i v i n g at p r a c t i c a l s o l u t i o n s . Thank you s i n c e r e l y fo r hearing our s t o r y . your time and patience. . We a p p r e c i a t e (equivalent to tha breathinq zona axponuro of tho hod-carricrs; (C) upwind and downwind (approximately) of tho stages, in tho gonaral area of the stages; (D) in the breathing zones of tho mixer operators; () in the general aroa of tho mixing operations; (F) one floor below tho spray operations; and (C) in tho general aroa of spray oporations (Tablo II), Sample Kumbe r 53 (A) 1 (A) 55 (B) 2 (C) 3 (C) 60 (D) 52 (D) 59 (E) 61 (E) 2 1 U 7 (F) k (0 ) 5 (G) 2 1 U9 (G) TABLE II PG&E AIR SAMPLES Area Asbestos Fibers , . T o t a l f/ml f/r.l*(>5 S p r a y operator's BZ II M BZ of investigator, stage, walking with close to 3p r a y hod-carrier 3.32 3.15 O .16 2.91 2.61+ 0 .11+ Area, stage + 1+0 f e e t Tair flow upwind of variable) single 0.13 0 .1 1 - A r e a , + 1+0 f e e t d o w n w i n d o f s t a g e (air flow variable) O .25 0.23 M i x i n g o perator's BZ (wind away from) Mixing operator's BZ (wind toward) 0.50 1 .1+2 0 . 1+2 1.25 Mixing area operators) (between two mixing 1.09 0.98 Mixing area operators) (between two mixing Background, 1 floor below spray operations, most air flow not t h rough the b u i l d i n g to filter, but variable. I . 3 I+ O.OII+ 1 .1 H 0.011 Area, between two stages (current to p u m p cut off at v a r i a b l e tines, total flow through filter uncertain) 0.033 A r e a , + 30 f e e t f r o m s t a g e s (2) O . O 71 0.036 0.061 A r e a , +_ 3 5 f e e t f r o m s t a g e , ( a i r flow in area u n c e r t a i n and variable) 0.36 0 . 31+ " P r e a e n t o c c u p a t i o n a l t h r e s h o l d l i m i t v a l u e of 5 f / m l is b a s e d on f i b e r s grea t e r than 5 mic r o m e t e r s in length. - 3-