Mechanics Should Treat All Friction Components Like They Contain Asbestos
WASHINGTON, DC - August 4, 2006 -Many auto mechanics do not know that old and replacement brakes and clutches may contain asbestos, according to the Occupational Safety and Health Administration (OSHA). The agency issued a safety bulletin explaining the best practices for dealing with asbestos dust in car repair shops.
"Mechanics should assume that all brakes have asbestos-type shoes," the bulletin warns. "Worn non-asbestos brake shoes cannot be readily distinguished from asbestos-type shoes." It recommends that mechanics perform brake and clutch work in an area isolated from other work areas. Employers should post large signs to inform workers not to eat, drink, or smoke in the brake and clutch work area. Pre-ground parts should be used whenever possible. If asbestos-containing materials must be drilled, grooved, or cut, low speeds should be used to limit dust.
Procedures to Reduce Dust from Asbestos Brakes
The bulletin reviews two ways of reducing asbestos brake dust-negative pressure enclosure/HEPA (high-efficiency particulate air) vacuum systems, and the low pressure/wet cleaning method. OSHA regulations require the use of either method, although the auto repair shop may use an equivalent method with demonstrated efficiency (CFR 1910.1001(f)(3)).
Using a negative pressure enclosure/HEPA vacuum system requires putting the asbestos brake or clutch assembly in a transparent enclosure with impermeable sleeves. A HEPA-filtered vacuum keeps the enclosure under negative pressure and may be used to loosen asbestos residue from the brake and clutch parts. The loosened material is put into a vacuum filter, which is sprayed with water mist. The vacuum filter is disposed of using sealed impermeable bags.
The low pressure/web cleaning method involves flooding the asbestos brake assembly with water containing a solvent or wetting agent. The brake support plate, brake shoes, and other parts should be washed before removing old brake shoes. Dry brushing is prohibited.
Legal Asbestos Exposure Requirements
The law requires that the asbestos level in the workplace be no greater than 0.1 fibers per cubic centimeter of air, taking an average over an 8-hour period. OSHA states that using the recommended methods of doing brake and clutch repair work will help keep asbestos dust below this level.
Although some newspaper investigators found that many repair shops do not follow proper safety procedures, government inspections have been infrequent. In the period from 1973 through 2003, for example, OSHA did not have a routine program of inspections or surprise visits at auto repair shops and rarely cited the businesses for asbestos violations, according to one Congressional report (Oversight Report, Congressman Dennis Kucinich, US House of Representatives, March 2004).
Even if an auto repair shop does lower airborne asbestos to the legal level, it is important to understand that asbestos is extremely hazardous and there is no safe level of asbestos exposure. According to the National Institute for Occupational Health and Safety (NIOSH) "all levels of asbestos exposure studied to date have demonstrated asbestos-related disease" and "there is no level of [asbestos] exposure below which clinical effects do not occur" (Asbestos Bibliography, DHHS (NIOSH) Publication No.97-162, p.25 (1997). Therefore, all avoidable exposures to asbestos should be prevented whenever possible. For more information about the risks of asbestos in automotive applications, see Asbestos Exposure & Auto Mechanics.