Document baZwEJ57OjpvODj7pXgyn0n7o

Bell Laboratories i"-.* : Evaluation of Employee Asbestos Exposure During Cable Installation m Hung Ceilings at Hew York Telephone Company at : April 25, 1 9 7 b ,*om: R, Deitchmar MH 73 35 3A203 x75 1 9 C . P. Lichtenwalne'" MH 7335 3A203 x5 39 9 ME "OR AND'JM rDR RECORD A- evaluation of employee exposure to asbestos tuning cable installation in nu'vg ceilings was *equeste-i bv the New Yo*k Tele phone Occupational H* a ' tn Working G**cud (OHV3 ) . Tne Bell Labora tories En virprmer t al -'ealtn and Safety Department, under the vjso. ces of tne AT AT OHWC, completed 3 o'* e 1 im in a-y survey or. . ` a n u a r v 25, d 97 ? which lead to a field survey on March 21, 1 979. Mr. J. C. Avery, Supervisor - Safety at New York Telephone Comt e n v , served as coordinator fo** this evaluation, an d Mr. R. McCullough , Installation Foremar at New York Te1epnone Company, gave irout leading to the evaluation design pa** ameter s. >um.m ar y An evaluation of employee asbestos exoosu'-e cubing CBble i r. s t a 1 lation in. hung ceilings at New Yc**k Telephone Company was made on Ma^ch 21, TO"7!. Major factors in potential employee asbestos exposure were examined. Conclusions include 'eooanaris ions for changes ir cu*i'2r3ert work practices and the eed for fu'-tne*" study. R eccmmerd aticr s The following a1"e recommended as a result of this study: 1. Additional air sampling data is necessary to fully evaluate employee exposure to asbestos during cable installation work activities in hur.g ceilings where sprayed -or. 3 sbesto s material is present. It may be possible to develop a work nomogram to indicate a safe working environment. 2. The practice 0f removing sprayed-or material for cable clamps or any other practice involving the 'eaoval of sp'myH-cn material should be avoided. 3. "his study does -ot ,,!mS?r.t sufficient data for OSH\ compli ance requiremer.ts. Medical and additional environmental CONFIDENTIAL PLAINTIFF'S EXHIBIT SWB-I3 003993 t. c r i - o * i r a m a v be r e 3 a s a 3 > v f o e t 1 c v e a a exposed t: 3 5 0 3 Svs fioe^'s H-ir: t n e s e w:*- violove?: d i ^i i" "i i '7, in vis study snsala oe irfor"?i one Vi'- 533:1 :r *-esjl ts . Tv asbestos 533^1es we ** e co 11 ebbed using tee p'*cccaur3S o obi ire " bv the National. Institute fo** Occupation el Safety ir d Heel be I'.' T'dl ) arc tie Occupational Safety ard Health Admin istr.atior Tme procedure involves collection of the airborne fibers or c st, = 11 filter, with late*- analysis usin' pease contrast v elect-on t, i orc sco dv . Tee filters used fo" collection of the samples were 37 mm Villi -- cellulose ester filters. The filters neve a nominal pov d iameter cf 0.8 micrometers (jit). Air was culled through bne filters using battery Doweled sampling pumps manufactured by Bendix at 2.0 liters ce>- minute or et 9.0 liters per -ninute with a pump manufactured by 'Jnicc. Tne pumps were calibrated using the scan bubble flowmeter technique. ve-iety of analysis techniques have been used to identify asbestos fibers and determine their concentrations in air. These induce oobical microscopy, electron microscopy, and K -ray dif fraction araivsis. Asbestos fiber identification and quantita tion in cccuoat ion a 1 and environmental air samples is difficult for a variety of ro3Sons: 1. Asbestos fibers a>-e generally present ir: low mass quantities even though fiber number concentrations may be hign. 2. Many instrumental analytical techniques carrot differentiate asbestos fibers from their non fibrous miner alogic oo1ymer ohs . 2. Airborne asbestos fibers can be below resolution limits of the ootical microscope (phase contrast). For identification of the various asbestos fiber types by electron microscopy, electron diffr=otion and microchemical aralyses must be performed which require extensive instru mentation 3rd analysis time. Tne cellulose filters in this study were aralyzed using phase cor vast mic-roscoov. microscopy was completed by Labo'-atcries Environmental ight micro scope uses phase er than. 5 pm in length and a Mr. c. P. Lichtenwalner Healtn and Safety Depa contrast to identify greater than 2:1 aspect of the tment. fiber s atic . CONFIDENTIAL 003994 3 75 - j : :' ar al VS 1 S f pr ISbeStOS was per forced t> y X-nv 1 i f f- ec t lor S 3 L ^ i- D'' i - s , M v'ltor. , *i * w h'^^v . '!z3 > O t <- f w j- ~ Ca i 1 ir3 Cable Ir. stall 3b tor.. ru^br of fals-9 ceiling tiles a*** '-aneve: C 3 b 1 is ^i 51 b v : 3) u s i r 3 3 wr^ sr. v<* b) u-ir". a Dull ::r' o) :>ushir. ; 3 b 1 itself ,o supporting si'-uolb". Tia installation wo'-k or hung ceilings involves. 1. Usually 2 b os i r cable; could be 53, r c, O'- 103 pair. 2. Re-entry when shooting troubles. Cable place-ient. in ceiling conduit because of some local flaws. Results Table T p*-esents tee results of air sampling To*- asbestos lu-irg cable installation wc'-k activities at 10 County Center Road ir: Waite Plains, Hew York. Two `lew York Telephone Company Install ers, Ralph Russo (33N: 090 IS 6717) and Ray Sussmann (33N: 069 28 4553), were wearing personal sampling equipment waile performing cable installation work activities. Tne results indicate short term exposure levels of 0.01 to 0.5? fibers oer cubic centimeter (fibers/cc). The presert Occupational Safety 3rd Health Adminis tration (03HA) Standard for asbestos exposure is 2 fibers/cc on an eight hour time weighted average, and a ceiling concentration (measured over fifteen minutes) of 13 fibers/cc. Medical exami nations are required by OSH A for any 7- to 3-hour time weighted average concentration of 0.1 fibe*'s/cc or greater. Also, the National Institute for Occupational Safety and Health (NI35H) Criteria Document roCOmmends an asbestos standard of 0.1 fibers/cc or. a time weighted basis and a ceiling level of 0.5 fibers/cc. Air sampling results for asbestos at 24 Railroad Avenue, j'-eenwich, Connecticut are shown in Table II. Hew York Telephone I-stallers Andy Vojt (SSM: 052 I1! 6033 ) and Dave Beecher (S3N: 945 7R 2 349 ) were equipped with air sampling apparatus while per forming cable placement work activities. The results indicate sh-rp-term exposure levels of 0.05 to 0.17 fibers/cc. CONfiDsi'iDAt 003995 "'iSCUSSl n . voe of so>-qvi1-or material (Descent, asbestos friability of 'is surface of to? spraveo-or Ti = :erii g. 2lev-ar:3 (distarc b?ower tne nunc, oeilirg ar : 3orava1-or material :n u. ooirt of cable lasnirc o. m etno d of c ab 1a placement o. cable size conation of wo*'k ooeracicr >. use of hung ceiling fo* return air plenum other wo*"k operations in the area Once there is knowledge that toe so^ayed-on material above a hung ceiling is asbestos, the results of this study indicate that per cent asbestos, method of cable Dlacement, cable size, and toe use of toe hung ceiling as a retu>T air plenum are rot sensitive oa-ameters affecting asbestos levels that would lead to exposures greater than 0.1 fibe^s/cc TWA. The point of cable lashing and the duration of tie wo**k ODeratior. a'-e critical parameters affecting exposure. The other work operations ir tie area param eter would roqUi.-e a case by case evaluation if tnese activities were disturbing -the sprayed-cn material. Tne friability of tr.a surface and the clearance are key parameters that were not stu died but are factors affecting asbestos exposure. At the present time, the difficulty in controlling employee asbestos exposure during these cable placement activities is the need for positive bulk identification of the sprayed-cn material as asbestos. From the results of this study, it may be possible to quantify certain parameters so that even if the sprayed-cn material is asbestos, employee exposure could be limited by proper work practices. Changes should immediately be made in practices concerned with cable lashing points. Quantification of the parameters of friability, clearance, and duration of the work operation looks inviting for development of a wvk nomogram to limit employee asbestos exposure. Further field studies and staged work operations are necessary for verification. 003996 in t/> ^ t ~ *1 -- \ T px"" J. D C^ou ~ r'l<a 7 o * Scots. M.D. Avo,*y - '{Y Is 1. - a ** > ^ein'netz, M.D. 7 . R. Consr. - 3TL J. Szh,"sibels *}. / . Mi Ikerir? -5 - D'C^cIa/b i \0a'. R. Deitcnmar. U) cknA C. P. Lichtenwalne-" CONFIDENTIAL 003997 7 abl ! . Asbestos Dugins? Cable Installat ior W~'"K Activities at 1" County Cent0'' R02;, Waite Flairs, 'law Yo*"< ?1, 1 97n 9<i 1 u iraLvsis of sonayei-cn ceiiirg material indicated 25 Deroer.c asoasv. r '<!zr"< Oner at ion Removin' Ceiling Tiles dieting 100 oair 3 0 ft. cable with cc**d Placing 75 oair 30 ft. cable with wi^e snake P1 a c i r g 75 d a i r 30 ft. cable by oushing Lashirg '5 Dai1" cable to ?'-iiers. Cashing 75 oair cable and coking cable through git-jen Removing sD*`ayed-on material f^om a girder for- = cable clamp A*-ea Sample in >-oom A'-ea Samole in hung ceiling Duration (minutest - 3J n 12 114 9 53 26 Volume of Ai>- SamDlei ( liters) 27 72 63 27 36 42 13 106 54 Asoestos Con c ertrat 10 { fi b er s/ cc ) 0.06 0.01 0.02 0.20 0.13 0.31 0.52 0.01 0.04 CONFIDENTIAL 003998 7 Table II. Asbestos yassu" everts Du** in? Cable Installation \-!zr-< Activities r. ?4 Railroad Aver ue , Greenwich, Connecticut '! srcs 21, 1 97 J a.^lw; analysis of so*'3yel-or ceiling material indicated 55 o e r c e r. o 3 `5 3't t. V S Wo^k 9oeratier Remcving Ceiling Tiles Placing 25 oai1" 4 9 ft. cable w i t n c o * d p 1 a c i n g 25 cair 49 ft. cable with wire snake Placing 25 oair 49 ft. cable by cashing Area Same1e-in room Area Samde- in. hung ceiling (acts as return air plenum) Duration (minutes) a 5 a 6 39 22 Volume :f Air gambled (liters) 27 45 27 54 73 44 Asbestos Concentre (fibers/ 9. 99 9. 95 0. 17 9.95 3.99 9.92 CONF'DeNTfAl 003999