Document YjvkpYYkLevZJovRbdKmMorMD

FILE NAME: Railroads (RR) DATE: 1972 Dec DOC#: RR063 DOCUMENT DESCRIPTION: Gov Report - An Investigation for the Federal Railroad Administration Conducted by the FAA Aeronautical Center Industrial Hygiene Section AIP, QUALITY- I T BALTIMORE A I'D OHIO TRAILS DESCENDING THE ALIAKOKT - PIEDMONT- GRADE IN NEST V DEC-1 NLA An in v e s tig a tio n fo r the F ed eral R a ilro ad A d n in is tr a tio n c o n d u c t e d by the FAA A e r o n a u t i c a l C e n t e r I n d u s t r i a l H y gien e S e c t i o n , Oklahoma. C i t y , Oklahoma DECEMBER 1972 '/ SUBMiTTED BY if'^ ^ K J. ^ ROBERT H. THOMPSON, P h .D . V C h ie f, In d u s tr ia l Hygiene S e c tio INTRODUCTION On 28-2 9 November 1972, a c t i n g upon a r e q u e s t from the F e d e r a l R a i l r o a d A d m i n i s t r a t i o n 's O f f i c e of S a f e t y , a i r q u a l i t y te s ts were 'made b y t h e FAA y A e r o n a u t ic'a 1 '. Cun t e r , ' I n d u s t r i a l H y g i e n e S e c t i o n , ' i n B a l t i m o r e and O h i o (BA-0 ) R a i l r o a d c a b o o s e c a r s n e a r C u m b e r l a n d , M ary'land. T h is i n v e s t i g a t i o n was conducted in r e s p o n s e to a com p l a i n t f i l e d with the State of Maryland, Department of Mental Health and H y g ie n e a l l e g i n g th a t stroke produced d u rin g p r o lo n g e d b r a k in g of r a i l r o a d c a r s cay be hazardous to the h e a lth of employees r id in g in c a b o o s e c a r s . The a i r in the c a r s was sampled i n an a tt e m p t to i d e n t i f y and q u a n t i fy the p a r t i c u la t e and vapor f r a c t i o n s o f the s u b je c t i v e l y d e te c ta b le m aterial anc to assess tha e f f e c t that such product m ight have an the occupants. PROCEDURE T h e s i t e s e l e c t e d f o r t h e t e s t s i s on. the B&O l i n e b e t n e e r . A l t a o i o n t , W. V i r g i n i a and P i e d m o n t , a s e v e n t e e n m i l e s e c t i o n o f t r a c k d e s c e n d in g on an approxim ate 2.07. grade-. T r a i n s n e g o t ia t in g t h i s g r a d e a p p ly brak es fo r v i r t u a l l y the e n t i r e d i s t a n c e and a p p a r e n t l y i n t h e p r o c e s s c r e a t e c o n s i d e r a b l e s.m.uke w h i c h i s r e a d i l y v i s i b l e o u t s i d e the t r a i n s . T h e r e ' was s p e c u l a t i o n by some t h a t the smoke may h a ve been caused w h o lly or in p a r t by b u r n in g f la n g e l u b r i c a n t on the t r a c k s . Page 2 T c s i s w e r e p e r f o r m e d on f o u r t r a i n s ; a m a n i f e s t t r a i n , two- c o a l d r a g s , and a g r a i n t r a i n in t h a t o r d e r . The f i r s t two t r a i n s were b o a r c ; : a t A lte r n a n t and th e l a s t two a t M o u n t a i n La k e P a r k , lid. A i r s a m p l i n g - i n s i d e -the c a b o o s e c a r s b eg an a t . A l t a m o n t and .ended, a t ... Piedmont on each run. s a m ? l t :g Ir. c o n v e r s a tio n s w ith brake shoe manufac t u r e r !s r e p r e s e n t a t iv e s , we lea rn ed something of the probable c o n te n ts of the com position sho es. Though g e n e r a l due to i t s p r o p r i e t a r y n a t u r e , the in fo r m a tio n did p r o v i d e some c l u e s t o t h e p y r o l y s i s p r o d u c t s we m i g h t e x p e c t t o f i n d in our sampling a c t iv i t i e s . Cr.e o b v io u s r e q u ir e m e n t in t h i s type of i n v e s t i g a t i o n i s t h a t a i l c f the sampling equipment must be p o r ta b le and b a tte r y or hand p o w e r e d . C o n s e q u e n t l y , we r e s o r t e d t o t h e u s e o f ( 1 ) d i r e c t r e a d i n g g a s s e l e c t o r tubes and (2) p e r s o n a l sam plers f o r v a p o r a n d - p a r t i c u l a t e 'c o lle c tio n . (L) D ir e c t reading gas d e te c to r tubes were used to measure s u l f u r d i o x i d e ( S O 2 ) , c a r b o n m o n o x i d e (CO) ammonia- (NH3 ) . and styren e (Cg.llgCH: CK2) ' any or a l l of w hich could have been present in the caboose a i r . In th is sampling method, a metered quantity of a ir is .a s p ir a te d through a glass tube containing a chemical selected to rea ct w ith a s p e c ific gas or vapor.' The r e a c tio n produces a c o lo r change in the tube c o n te n ts , t h e ,le n g t h of which is p r o p o r tio n a l to the con- % c e n tra tio n of the gas in the sample of a i r . Page 3 / (2) P e r s o n a l c a m p i e r i , a r e s m a l l b a t t e r y o p e r a tec! pumps w h i c h a t t a c h to the w earers c l o t h i n g and a s p i r a t e a i r from h is b r e a t h i n g zo n a-at a c o n s t a n t flo w ra te th ro u g h o u t the samp lin g period. One sam pler was u s e d to draw a i r th r o u g h a rar e r membrana f i l t e r h a vin g a pore s i z e o f 0 .4 5 m icron (p) . The p a r t i c u l a t e s trapped on the f i l t e r s u r f a c e were re turned to the FA. Aeronautical C en ter. In d u srria i Hygiene Laboratory where they were weighed and then examinee wicr. a lig h t m i c r o s c o p e f o r - i d e n t i f i c a t i o n a n d s i z i n g . A n other sam pler was used f o r vapor c c l l e c t z o n by draw i n g a i r t h r o u g h a 1 2 7 r a x 6mm g l a s s t u b e c o n t a i n i n g a c e i - v a t e d c h a r c o a l . T h e s e tubes w ere s e a l e d a f t e r sam pling and returned to the laboratory' where they were desorbed with carbon d i s u lf i d e and analyzed on a g a s - l i q u i d chromatograph using a flame io n iz a tio n detec t o r . RESULTS ' On t h e f i r s t r u n , a m a n i f e s t t r a i n , we d e t e c t e d n c c o n t a m i n a t i o n in the caboose e ith e r s u b je c t iv e ly or by te s t. On th e second r u n , the smoke became v e r y dense and v i s i b i l i t y in the caboose was sev e re ly r e s t r i c t e d . ' Although i t was c e r ta in ly an a n n o y i n g c o n d i t i o n , we d i d n o t f i n d I t i r r i t a t i n g o r r e s t r i c t i v e t o ___ our breathing throughout the f i f t y minute sampling period. Page h h e w o u l d c l a s s i f y smoke c o n c e n t r a t i o n s or. t h e . t h i r d and r ou rt ih runs os medium and l i g h t r e s p e c t i v e l y when compared v:ith the c o n d i tion s encountered in the second run. \ - On t h e b a s i s o f o u r o b s e r v a t i o n s and t e s t s , we c o n c l u d e t h a t the : smoke a r i s e s f r o m t h e 1" b u r n i n g " o f t h e b r a k e s h o e s and t e a t l i t t l e , i f an}' , cones from burning fla n g e lu b r ic a n t . The g a s , v a p o r and p a r t i c u l a t e s a m p l i n g r e s u l t s a r e re c o rd e d on page 8 . GASES AND VAPORS The only contaminant present in measurable amounts using the d i r e c t r e a d i n g g a s d e t e c t o r t u b e s was c a r b o n m o n o x i d e . I t was d e te c te d during each run, but only in trace (I) q u a n t i t i e s , less than 10 p a r t s p e r m i l l i o n p a r t s o f a i r s a m p le d (ppm). The o t h e r g a s e s i . e . S O p , l'iHg a n d s t y r e n e , i f p r e s e n t , w e r e i n c o n c e n t r e t i o n s t o o low t o measure by th is method. The a c t iv a t e d ch arco al - gas chromatography method used fo r c o l l e c t i o n and a n a l y s i s c f v a p o r . c o n t a m i n a n t s i s e x t r e m e l y s e n s i t i v e to" low c o n c e n t r a t i o n s . O n l y d u r i n g t h e s e c o n d ^ r u n d i d we c o l l e c t any meas. ur e- a b l e , t h o u g h m i n u t e , q u a n t i t y o f m a t e r i a l . .- c h r o m a t o g r a p h i c " f i n g e r - "U p r i n t " o f t h i s samp l.e b o r e a s t r o n g r e s e m b l a n c e t o a s i m i l a r chroma t o - K g ra m o f p y r o l y z e d b r a k e s h o e m a t e r i a l . A l t h o u g h t h e components o f the jj sample represent p h y sio lo g ica lly in s ig n ific a n t a ir-b o m e concentrations o f c o n t a m i n a n t s t h a t c o u l d b e e m i t t e d f r o m t h e b r a k e s h o e s , we a r e c o n tin u in g w ith te s ts to id e n t ify and q u an tsfy each. Page 5 P A R T IC U lA T a S P a r t i c u l a t e c o n c e n t r a t i o n s r a n g e d f r o m 0 n r 11 i g . tir.s p e r c u b i c m e t e r (mg/l-i ) o f a i r s a m p l e d on t h e f i r s t r u n t o 1 9 . 7 5 rr.g/lr on th e second run. ' 'M icroscopic examination of the f i l t e r s revealed that : v i r t u a l l y a l l o f the c o ll e c t e d m a t e r i a l vas b l a c k smoke p a r t i c l e s ( s o o t ) r a n g i n g i n s i c e f r o m <( 1 m i c r o n ( 1 / 2 5 , 0 0 0 i n c h ) t o 6 m i c r o n We caw n o a s b e s t o s f i b e r s on. a m ' o f t h e f i i t s r s . C ONCLUSIONS A i r q u a l i t y standards of the O c c u p a tio n a l S a f e t y and Health A d m i n i s t r a t i o n (OSKA) e s t a b l i s h e d by the F e d e r a l O c c u p a t i o n a l S a f e t y and Health: A c t of 1970 c o n t a i n a i r - b o r n e c o n c e n t r a t i o n s of s u b s t a n c e s to which i t is b e l i e v e d t h a t n e a r ly a l l workers nay be r e p e a t e d l y e x p o s e d 'cay a f t e r day (8 h r ) , we ek a f t e r we ek (5 d a y s ) w ithout adverse e ffe c t. They are tLme-weighted concentretions w h i c h means t h a t e x c u r s i o n s a b o v e th e l i m i t may be p e r m i t t e d p r o v i d ed they are compensated by e q u i v a l e n t e x c u r s io n s below the l i m i t during the work day. These threshold lim it values (TLV's) are based on the b e s t a v a i l a b l e in fo r m a t io n from i n d u s t r i a l e x p e r i e n c e , from e x p e r i m e n t a l human and e x p e r i m e n t a l a n im a l s t u d i e s , or p o s s i b l y com binations of the three. T h re sh o ld lim it values fo r a i l a i r - b o m e su b sta n ce s sampled d i r e c t l y on the t r a in s are in c lu d e d in the t a b l e on page 8. Only the TLV f o r n u isan ce p a r t i c u l a t e s of 10ng/MJ was exceeded during the 50 m in u t e s o f sam pling on ru n number two when th e c o n c e n t r a t i o n re a c h ed 19.75 m g / lP . However, a tim e -w e igh te d a v e r a g e f o r an 8 hour Page 6 _ p e rio d w hich inclu d ed only one such exposure, or even two, would f a l l f a r b e lo w th e TLV.- The 50 m in u te e x c u r s i o n a b o v e the TLV would be e a s i l y compcnaaced by the much lon g er exposure to a i r not co ntam inated w i t h th e smoke. T his sam ple which was c o l l e c t e d in th e caboo se o f a long c o a l drag probably rep rese n ts the worst c o n d itio n of th is p ar t i c u l a r smoke problem th a t would be encountered on t h is l i n e . A s b e s t o s , w h ic h i s an i m p o r t a n t i n g r e d i e n t i n b r a k e s h o e s , was n o t d e t e c t e d i n i t s h a z a r d o u s ( f i b r o u s ) f o r m i r . a n y c f t h e a i r s a m p l e s . Then s u b j e c t e d t o j p e m p e r a t u r e s _o_ 9 0 0 t , f i b r o u s a s b e s t o s i s r e d u c e d t o a r e l a t i v e l y inccucus powder. C a rb o n m onoxide, t r a c e s of which were d e t e c t e d on each ru n , is probably tra ce a b le to the heaters used in the c a r s . We h a v e c h e c k e d T L V ' s f o r o t h e r s u b s t a n c e s w h i c h may b e d e g r a d a t i o n p r o d u c ts of p yro ly z ed c o m p o sitio n brake shoes such as phenols and fo r m a ld e h y d e and f i n d t h a t the c o n c e n t r a t i o n s o f our ch ro m ato - g r a p h ic a lly separated c h a rc o a l tube sample components are fa r below such lim its . In. summary, a i r s a m p l i n g i n c a b o o s e ' c a r s c f f o u r B&O t r a i n s d e s c e n d i n g t h e g r a d e f r o m A l t a n o n t , W. V i r g i n i a t o P i e d m o n t , W. V i r g i n i a r e v e a l e d o n l y t r a c e s o f CO and no m e a s u r a b l e amount o f SO2 , and s t y r e n e . D u r in g one run th e TLV f o r n u is a n c e p a r t i c u l a t e s was exceeded b r i e f l y b u t n o t s i g n i f i c a n t l y v/hen t h e p e r i o d - o f e x p o s u r e was c o n s i d e r e d . O t h e r c o l l e c t e d v a p o r com ponents o f the b r a k e s h o e smoke were p r e s e n t in only tra ce q u a n t i t i e s and not p h y s i o l o g i c a l l y s i g n i f i c a n t .