Document NE5980w28ZMNjmOaRmrayn4vw

PLAINTIFF'S EXHIBIT CHR-228 THE ENCLOSCO INFORMATION WAS ORTHEREO FROM A l/RRIETY OF SOURCES. IT DOCS' NOT NECESSARILY REFLECT THE OPINIONS OR OFFICIAL POLICIES OF NIOSH. October 1978 FRICTION MATERIALS WORK PRACTICES GUIDE USE DUST COLLECTION EQUIPMENT WHEN MACHINING 2 INTRODUCTION The purpose of this booklet is to provide practical guidelines for brake and clutch service mechanics in the hanoling and process ing of asbestos containing friction materials and in the maintenance and repair of brake and clutch assemblies on which the materials are installed. Adherence to the recommended work practices will reduce employee exposure to airborne concentrations of asbestos dust and will assist employers in complying with government regulations. This area is regulated by federal, state and local authorities. We caution that you may not rely on strict adherence to the work practices recommended herein as assuring compliance with these regulations, oecause (a) they are subject to amenoment: (b) there are on-going administrative interpretations of these regulations; and (c) particular field conditions may vary. You should direct all auestions relating to compliance with regulations to the appropriate regulatory agencies. ASBESTOS AND FRICTION MATERIALS Most molded friction materials contain about 50% asbestos some woven materials over 90%. In molded materials, resin binders prevent the release of asbestos fibers during normal handling. Woven friction materials, normally used only in con struction and industrial applications, must be handled with care to avoid Creating dust as the asbestos fibers are less firmly bound into the product. Potentially hazardous airborne concentrations of asbestos dust can be created by improper cleaning and handling of worn brake and clutch assemblies, uncontrolled machining operations and poor housekeeping. Breathing excessive quantities of asbestos fiber can cause respiratory disease and cancer. Smoking greatly increases the risk of lung cancer among asbestos workers. Prevention of asbestos dust exposure is the only known method of eliminating asbestosrelated disease among those working with asbestos containing products. Proper work practices offer the best assurance of providing exposure safeguards for workers removing, installing and machin ing asbestos containing friction materials. 3 DO NOT USE AN AIR HOSE FOR CLEANING 4 SUMMARY OF OSHA ASBESTOS STANDARD EFFECTIVE JULY 1,1976 Under the current standard, it is the employer's responsibility to assure that exposure of employees does not exceed the following permissible exposure levels. a. Eight-hour time-weighted average: Two fibers, longer than five micrometers, per cubic centimeter. b. Ceiling (Peak) concentrations: Ten fibers, longer than five micrometers, per cubic centimeter. Engineering controls such as isolation, enclosure, exhaust ventila tion and dust collection are the preferred methods for meeting tne prescribed exposure limits. All external surfaces must be main tained free of asbestos fiber accumulation. Respiratory protection is required whenever airborne fiber con centrations exceed either the permissible time weighted average level or the permissible ceiling concentration. Protective clothing is required whenever airborne fiber concentrations exceed the permissible ceiling level. Caution signs, change rooms and employee notification are required where asoestos fiber concen trations exceed permissible exposure limits. The standard re quires that all workplaces where asbestos fibers may De released shall be monitored to determine exposure levels, and regular monitoring is required where exposure levels are expected to exceed permissiDie limits. Employers must maintain records of monitoring required by the standard. They must also provide or make available medical examinations for employees exposed to airborne concentrations of asbestos fibers. 5 USE VACUUM OR WET METHODS FOR CLEANING HANDLING NEW FRICTION MATERIALS Handling new disc brake assemblies. l>neti brake shoes, clutch facings and brake blocks purchased in individual boxed sets is unlikely to create significant airborne concentrations of asbestos dust. If the parts are purcnased in bulk quantities, abrasion during shipment may result in the accumulation of dust in shipping containers. Dust should be removed by vacuuming or cleaning with a damp cloth. Whenever possible, purchase friction materials preground and ready for installation. This may keep dust levels beiow OSHA maximums and eliminate the need for respiratory protection, restricted areas, regular monitoring, special clothing, change rooms and employee notification. REMOVING WORN FRICTION MATERIALS Asbestos fibers in disc brake linings, drum brake linings, blocks and dry clutch facings are locked into tne product with resin binders which prevent the release of asbestos fiber auring normal installation. Heat ana abrasion during normal use may generate dust containing asbestos. Some dust will accumulate in brake and clutch assemblies. When removing worn friction materials, remove the accumulated dust m the assemblies with an industrial vacuum cleaner equipped with a high efficiency filter system. If such equipment is not available, dust can be removed with a damp clotn. Do not use compressed air or dry brushing for cleaning. Use a NIOSH approved respirator when removing worn friction materials, or cleaning brake or clutch assemblies. MACHINING FRICTION MATERIALS There is an increasing trend for manufacturers and rebutlders to provide brake lining and clutch facings pre-drillea and ore-ground in final assembly form. In the esse of truck brake blocks, various oversize thicknesses are available. However, there are some instances where field machining is necessary. This is particularly true for construction and industrial equipment applications which may require machining of blocks, slab stock or roll lining. Dust generation can be minimized or eliminated during arcing of brake blocks by lathe turning at low speed rather than grinding. Whenever possible friction materials should be cut to length with a shear rather than a saw or abrasive cut-off wheel. 7 DO NOT SWEEP IN WORK AREA - USE VACUUM METHOD 8 DUST COLLECTION METHODS When asbestos-containing friction materials are machined, i.e.. drilled, ground, grooved, cut or beveled, the dust created contains asbestos fibers which may become airborne unless adeouate dust controls are employed. The preferred method for minimizing airborne dust from machining operations is local exhaust ventila tion. A local exhaust ventilation system consists of dust collection hoods or enclosures connected by duct work or piping to a dust collection filter and a suction source. The two operations that offer the greatest potential for generation of excessive amounts of airborne asbestos fiber are arc grinding and beveling of lined brake shoes and linings or brake blocks. Grinding machines used for these operations must oe provided with exhaust ventilation to maintain worker exposures within permissible levels. If a central exhaust system is not available. NIOSH (National Institute for Occupational Safety and Health) has stated that, at a miminum. the dust bag of the arcing machine shall be removed and replaced with the hose from a high efficiency industrial vacuum. For large volume machining operations that operate on a con tinuous basis, the preferred dust collection device is a faoric filter or baghouse. with a heavy-duty exhaust fan as the suction source. The dust collector must meet the air-cleaning requirements of the Federal Environmental Protection Agency Emission Standard for Asbestos. Approval must be obtained trcm EPA for installation and operation of each system. OTHER METHODS OF MINIMIZING DUST EXPOSURE Whenever possible machining and repair operations should be isolated from other work areas in a restricted area to prevent unnecessary exposure of other workers. Entrances to restricted areas shall be posted with asbestos exposure warning signs as follows: Asbestos Dust Hazard Avoid Breathing Dust Wear Assigned Protective Equipment Do Not Remain In Area Unless Your Work Requires It Breathing Asbestos Dust May Be Hazardous To Your Health 9 WEAR AN APPROVED RESPIRATOR IF UNABLE TO AVOID DUST 10 Good housekeeping is essential in a workplace where asbestos containing materials are handled, industrial vacuum cleaners equipped with multiple stage high efficiency filters should be used for removing accumulations of asbestos dust and waste. Never use compressed air or dry sweeping for cleaning. Water or other dust suppressants should be applied if brooms are used. Good personal hygiene oractices are important in minimizing asbestos dust exposure. Do not smoke. Wash before eating. Shower after work. Change to work clothes upon arrival at work and change from work clothes at conclusion of work. Work clotning should not be taken home. Laundering of asbestos contaminated clothing shall be done so as to prevent the release of airborne asbestos fibers in excess of the exposure limits. DISPOSAL OF FRICTION MATERIAL DUST AND WASTE Dispose of vacuum cleaner waste and asbestos containing cleaning materials in plastic bags or other sealed containers, with the following warning label printed on the container: Caution Contains Asbestos Fibers Avoid Creating Dust Breathing Asbestos Dust May Cause Serious Bodily Harm Use a NIOSH approved respirator when servicing vacuum cleaners, dust collectors, or handling any asbestos-containing waste materials. Asbestos-containing waste materials must be collected, process ed. packaged, transported and Deposited in such fashion that no visible emissions are generated to me atmosphere. All wastes must be disposed of at sites operated in accordance with applicable laws and regulations. 11 SOURCES OF ADDITIONAL INFORMATION 'Standard (or Exposure to Asbestos Oust' (Code of Federal Regulations. Title 29. 1910.10011-OSHA 'National Emissions Standards (or Hazardous Air Pollutants--Asbestos and Mercury" (Code of Federal Regulations Title 40. Chapter l.SubchaoterC. Part 61. Subparts A. B)--EPA "Fundamentals Governing the Design and Operation of Local Exhaust Systems." ANSI Z9.2-1971 ($7 00) anc "Practices tor Respiratory Protection." ANSI Z8S.21969 <5.50)--ANSI "Industrial Ventilation Manual" ($8.00--ACGIH For other information, a user may contact the manufacturer supplying his friction materials, the Asbestos intormation Association or the Friction Materials Stand ards Institute. ACGIH American Conference of Governmental Industrial Hygienists Committee on Industrial Ventilation P 0. Box 16153 Lansing. Ml 48901 ANSI American National Standards Institute 1430 Broadway New York. NY 10018 AIA Asbestos Information Association 1745 Jefferson Davis Highway Arlington. VA 22202 EPA Environmental Protection Agency Public Information Center 401 M Street SW Washington, DC 20460 FMSI Friction Materials Standards institute East 210 Route 4 Paramus, NJ 07652 OSHA Occupational Safety and Health Administration Office of Information Washington. DC 20210 October 1978