Document p2LMO86GkB578gB0On93nN9ek

Case: 48106-3 Ref.: 1893 AT&T Bell Laboratories 600 Mountain Avenue Murray Hill New Jersey 07974 Phone (201) 582-3000 January 31, 1984 Ronald F. Smith Southern New England Telephone 195 Church Street, 9th Floor New Haven, Connecticut 06506 Dear Ron: The three air filter cassettes you submitted have been analyzed for asbestos fibers. Filter samples were analyzed in accordance with NIOSH P&CAM 239. This method involves sizing and counting fibers using a phase contrast microscope. All fibers which have a physical dimension longer than 5 micrometers (pm) and a length to diameter ratio of 3 to 1 or greater, are counted. Fiber concentrations and 8-hour time weighted average (TWA) concentrations, expressed as fibers per cubic centimeter (fibers/ cc), were calculated from the sampling data you provided and the analytical data. Results are listed on the attached table. The Occupational Safety and Health Administration's (OSHA) Emergency Temporary Standard (ETS) of 0.5 fibers/cc (8-hour time weighted average exposure limit) is now in effect. The OSHA 8-hour action level is 0.1 fibers/cc. Please call if you have any questions. Sincerely, MH-78691-PAH-jve Attachment: Table 1 Copy to: W. D. Luty F. L. Provato, M.D. ---J. H. Degen W. J. Schreibeis G. M. Wilkening CONF1DENTIA1 Patricia A. Huggins (201) 582-7927 003849 Airborne Fiber Concentrations SNET - Hung C eiling Work January 24, 1984 C o U 40 3CO U O * P CO o<D ooc CMc r- U P<0 u*>* tA P Sc qj QJ .3 Uc u.- oO CO o o oo cm r-. co eg * oo V) "3 S- 0) QJ p -o c to *- 3 O* Ps. U_ O o <-> 03 H- QJ O -- Q. E* E <0 . 3 VO** OU o *O3" CM CVI C, QJ o 'o.p E <0 t* t<no o&s. wE c o QJ P CLfE<0 (iJ. co in O o CM 01 .o (O u c o '-- CT v- c QJ *1h- r-- cn a) cu tc cn cc 33 QT -C 0) O 40 u c o -- o> 0<4- C ) H- i-- r* cn 0) Co c cn cc 33 or x: QJ a. CO <Eo zo CO c 3* <o CM CM tr-- CO O O io- QJ s- 3 V) o Q~ X0) o c ccr> E 3 t/> 4tn0 QJ P<o CM E E f-- 3 U r-- 40 u c o op 40 o u II p p 40 C QJ a> u 40 *3 X r-" c QJ QJ OX c <n O u <o P QJ 40 r4- JO QJ 40 0T3 40 * tin o x> 4- S- C QJ O > 40 *3 QJ QJ f 03 QJ 03 P QJ 40 4- P P O U #- O 0) cnoD r-- L- f- c CL L- Ql T- OO* uu tn n QJ CO O QJ E L. S. r- * U f-- 40 P >i 40 E a l. -a QJ 3 Op O o t- J= l_ oo au p 5 c QJ z L. o> u 3 03 V> QJ O QJ c JT Po c p 00 3 p< O 40 pc cn u L. c P * tn c L. c L. QJ 3 *r" QJ JO U O <o c c E u. o o 1 QJ CO tm 003850