Document opgXDo07ZKXk8zq64ebnXb9o

Industrial Hygiene Forum Franklin O. Griflltb, Ph.D. Department Editor The IndustrialHfgkmForam is designedas a medium of exchange far members mat readers who wishto share their "know-how" with othersyet avoidthe necessity ofpreparlug a fad and detailed manuscript on the subject. The is yens opportunity to thant with ethers yam '"know-how," timely tips, mw idem. ate, on any aspect of Industrial hfgkm. Mxeeptiem at* matters of epmkm and comments an published manuscripts; these will ha published elsewhere in the Journal Submissions should ha signed and! markedfoe pubikmkm m the Forma. Contributions to the Industrial Hygiene Foram wtHnot bepeerreviewedbut theright k reserved to edit accepted contribution*. The Mtm of the "Forum'' of esstrse will depend upon the eontributiom from you, our readers. Foe consideration. sand year eeairibm lions directly to Franklin D. Griffith, Phi!., Industrial Hygiene Forum, AIMA Journal 473 Wotf ledges Parkway, Akron, OH 4431l-mf. (21*1 7*2-72*4. Asbestos Exposure Associated with Automotive Brake Repair in Pennsylvania * L. LAMONT MOORE Safety Sciences Department. Indiana University of Pennsylvania. 20S Uhier Hall. Indiana. PA 15705 Introduction Automobile mechanics are potentially exposed to asbestos fibers released' durin| brake repair work in service stations, car dealer* ships and mutlfer shops nationwide. Asbes tos libers are released when serv ice mechan ics clean dust residue from contaminated drum or wheel parts. Personal samples were collected from the breathing zones of auto mobile mechanics to estimate their asbestos exposure while performing actual brake re moval and repair work. Exposure measure ments were made in thirty-one different facil ities with widely diverse work practices. The estimated average asbestos exposure during actual repair work was <0.05 fiber per cubic centimeter (f< cc| based on thirty-live sepa rate samples. If zero exposure were assumed for the unsampled portions of these shifts, the mean eight-hour, time-weighted average would have been <0.002 f, ce. A-12 Materials md Methods Personal samples were drawn from the breath ing /ones of employees performing brake service work. Sampling encompassed the entire period required to complete the as signed tasks. In most instances the assign ment consisted of pulling all four wheels, visually inspecting the front disc pads, then removing and replacing both sets of rear brake shoes. Each sample was collected on in 0.8-tim pore size. 25-mm diameter mixed cellulose ester filter mounted in an open-face. 5-cm diameter cassette. Individual filien were at tached to the employees' outer garments in the breathing zone. Air was drawn through these lilters using MSA Model C sampling pumps. The flow rate on each pump was set at 1.7 Lpm as established by prior calibra tion by a soapbubble meter. The sampling rate was checked periodically and adjusted if necessary to maintain the desired setting. A t the conclusion of each survey, the individual cassette was scaled, labeled and submitted to an approved industrial hygiene laboratory. At the laboratory, a small portion of each filler was cut and mounted on a glass slide in a medium consisting of dimethylphthalaie and diethyloxalate. then covered with a glass cover slip. Each sample was subsequently counted on a Zeiss microscope equipped with phase contrast and a porton reticle. The reticle is calibrated at a magnification of 400 times with the stage micrometer from Bausch and Lomb Optical with scales of 0.10 mm and 0.01 mm. Results ami Dl&amtem One major finding oMhisstudvjwas that automobile mechanics were very well educated about the danger of using compressed a|tocJeandintlromwhgjljjjjgkenjun^ Compressed air was used on a limited basis in only one of the thirty-one facilities surveyed. The data summarized in Table I suggest that employee exposure typically falls well below the OSH A permissible exposure limit (PEL) of 0.2 f. cc. We point out that these measurements were collected during repairs on a representative number of vehicle msktv and models, in a broad spectrum of repair facilities employing a wide diversity of work practices. In 7Sr-r of the instances where exposure exceeded the mean (0.05 f cc). poor work practices were involved. Where employees utilized good work practices -- such as the use of a spray-ty pe, aerosol liquid cleaner -- seventy percent of the exposure measure ments fell below the mean. Our findings seem somewhat lower than those reported by Kauppinenand Korhonen,1' but this may be due to less frequent use of compressed air for cleaning. In most ol the Pennsylvania facilities survey ed, each employ ee performed an average of two or three brake repairs per week. Based on our inter views. it would be unusual for a mechanic to perform brake service work on more than one vehicle per day. The mean length of time required to com plete these brake jobs was 29 min. If one expects exposure to average <0.05 f> cc dur ing this high risk period with zero exposure assumed for the remainder of the shift, the employee's eight-hour, time-weighted aver age could be predicted to average <0.002 fi cc on days when brake repairs are under taken. Condiaiom Appendix Fto29CFR 1910.1001 summarizes non-mandatory work practices and engineer ing controls forautomotivc brake repair operations.,i> Our study supports OSHA's posi tion that management in the automobile serv ice industry can keep employee exposure below 0.1 f ee and avoid costly compliance programs. The most readily accepted, costeffective approach seems to be the use of spray-ty pe, aerosol cans of brake cleaning solvents. These containers deliver a mist w ith considerably less force than shop air hoses fitted with a solvent delivery system. The aerosol spray approach may be equally as TAIL*I Summary of Asboatoa Expoawv Monitoring fiptMICV Mmmmemrnm Mange tor Owatfane* a* - *--s--a (ntkmrtm) toe ConcantratiM* In mmlm (Median) (Maon) (Manga) 3S 10-60 <0.02 <0.03 <0.01-0.16 *Ejtpoura otomatM abova raftact actual time-weighted averages lor km sampling period during when brake oarmea work was earned out not ttw full eight-hour shift. cwg nm tmwwm inimimirnipiin mmimii m-- Ununldt I \ HWBUI0007531 V effective U vacuum systems equipped with HEPA niters, provided that the contami nated liquid drippings are caught in a drip pan and disposed of in accordance with appropriate waste disposal regulations. Other work practices which deserve man agement consideration include limiting the height of the car-lift or service rack so that wheel parts are not disassembled at (or above) the level of the employee's breathing /one and prohibiting employees from dump ing dust residue from brake drums directly on the shop floor. Contaminated dust can be vacuumed or carefully dumped into waste liquid containers which subsequently will be used to catch aerosol drippings. yReferences 1. Kaupplnan, T. and K. Korhanon: Expo sure to Asbestos During Brake Mainte nance of Automotive Vehicles by Dif ferent Methods. Am. Ind. Hyg. Assoc. J. 48f5):499-504 (1987). 2. "Asbestos. Tremoiite. Anthophyilite and Antinolite," Code of Federal Regulations. Title 29. Subtitle B. Part 1910. Subpart Z. June 20.1986. Ribavirin -- Exposure to Health Care Workers SUSAN B. LEE Safety Director. The Children's Hospital. 300 Longwood Ave.. Boston. M A 02115 employee complaints of irritation and concerns about reproductive toxicity: to report results of environmental mon itoring for airborne ribavirin. Administration of Ribavirin exposed health care workers are women in their childbearingyears. the potential lorletal death or damage was of even higher concern than the above-mentioned acute symptoms. Method and Results A sterile dilution of lyophili/ed ribavirin is In the absence of any data on the level of Introduction prepared such that the concentration of the solution is 20 mg, mL. The small-particle exposure and to most prudently address the potential hazard to unborn children of stall I Ribavirin (l-beta-D-ribofuranosyl-l.2.4 tri- aerosol generator (SPAG-2) delivers the members, it was recommended that preg azole-3-carboxamide). an antiviral drug, has solution as a small, uniform size aerosol nant workers (or those attempting to become the Food and Drug Administration (FDA) (95`t of particles < 5 q diam),J' which is pregnant) be excluded from any exposure by 4 approval for administration as an aerosol to "contained" inside a hood or tent around the not caring for patients on ribavirin. selected infants and young children with patient's breathing zone. The average aero In response to the acute symptoms de severe lower-respiratory tract infections due sol concentration fora 12 hr period would be to respiratory syncytial virus (RSV).'" 190 qg. L (0.19 mg; L) of air. The aerosol is scribed above, an industrial hygiene survey I Ribavirin (VirazoleTM) has been sold in Mexico for almost twenty years under the administered for 20 of 24 hr for five consecu tive days. was conducted using a calibrated Bcndix pump, open-face. 37 mm cassettes and 0.8 qMCEF. Preliminary results showed ambi brand name Vilona as an orally administered remedy for viral infections. It is noteworthy Occupational Exposure ent exposure levels of 2.35 to 2.80 mg. m* airborne dust. Based on these results and as one of several drugs being tested for Direct exposure occurs when nurses, respira assuming the "dust" was ribavirin, the Safety- treatment of AIDS and AIDS related com tory therapists, doctors or others actually Office required the following protection for plex (ARC).1*' enter the tent to care for the patient. Because staff who enter the room while ribavirin Warnings, contraindications, precautions these patients are usually very young and aerosol was being administered: and a description of adverse reactions are quite ill. the tasks involved in caring for them I given in, the product monograph, as they may be quite frequent and of relatively tong to prevent eye irritation -- tight-fitting might afreet the patient and the treatment of duration (15 min to 1 hr at a time). It should goggles: the disease. be noted that the care is to a "babe in arms." to prevent inhalation -- approved dust Some of the potential adverse health effects and this exposure is in the employee's breath i for health care workers administering riba ing zone. mist respirators!3M Company 8710. or equivalent) properly worn and fitted: virin may be carcinogenesis, fertility impair Indirect exposure may occur because the to prevent inadvertent ingestion -- use ment and fetotoxicity. Use of the drug is tent or hood is not an airtight filtered system. of long-sleeved gow ns and latex gloves, 4 contraindicated in women or girls who are The pressure inside the tent is positive with pregnant or may become pregnant during respect to the room. and. therefore, the air scrupulous personal hygiene, hand and any exposed skin surface washing: exposure to ribavirin. Ribavirin has been found to be teratolethal and/or embryolethal in nearly all animal species in which it has been tested. It has shown structural and meta bolic similarity to other cytotoxic agents, is mutagenic in mammalian cell culture and has borne ribavirin particles may leak into the room creating potential for inhalation to anyone entering the room. Direct caregivers who may enter and leave the room to check on the patient's status, without entering the tent, may be exposed in this way. The greater to assure employees understand potential hazards, routes of entry and limitations of protective measures -- dissemination of product literature and training sessions. Using an identical method and collecting caused cell transformation in an in vitro concern of indirect exposure is to the par five additional samples, we (at the Children's mammalian system. The purpose of this paper is as follows: ents. who may visit anytime day or night and who may spend the entire night in the patient's room. Hospital) were unable to confirm the airborne dust concentration seen in the first two sam ples. Alt other samples were below the limit to describe the method of administra tion ofaerosolized ribavirin as the source of occupational exposure to the drug; E m ployees'com plaints of headaches, burn ing and dryness of the eyes, coughing and dryness of the upper respiratory tract resulted of detection in exposed and non-exposed areas. Based on these results, the requirement for todcscribe policies and procedures devel in the Safety Office's becoming involved in in strict use of personal protective equipment oped by one hospital in the absence of vestigating the matter of occupational expo was limited to the occasions when employees any data on the level of exposure, given sure to ribavirin. Since the majority of the enter the tent. l 4m. Ind. Hyt Assoc J. (49) I JoiMnr. 1988 CaoynaM itM. teancan ixduunal HygwM Mmemtam A-13 HWBUI0007532