Document rpz2LObXKbmMz2521gnnZE1Jv

FILE NAME: Abex (ABX) DATE: 1978 Oct DOC#: ABX106 DOCUMENT DESCRIPTION: FMSI - Friction Materials Work Practices Guide October 1978 FRICTION MATERIALS WORK PRACTICES GUIDE FMSI--0301 F M SI 03485 SCF-LLF-07440 ir USE DUST COLLECTION EQUIPMENT WHEN MACHINING F M S I03486 INTRODUCTION The purpose of this booklet is to provide practical guidelines for brake and clutch service m echanics in the handling and process ing of a sbestos containing friction m aterials and in the maintenance and repair of brake and clutch assem blies on which the materials are installed. Adherence to the recommended work practices will reduce employee exposure to airborne concentrations of asbestos dust and will a s s is t em p lo yers in c o m p ly in g w ith gove rn m e n t 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 a s assuring compliance with these regulations, because (a) they are subject to amendment; (b) there are on going adm inistrative interpretations of these regulations; and (c) particular field conditions may vary. You should direct all questions relating to com pliance with regulations to the appropriate regulatory agencies. ASBESTOS AND FRICTION MATERIALS Most molded friction materials contain about 5 0 % 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, m ust 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 m achining operations and poor housekeeping. Breathing excessive quantities of asbestos fiber can cause respiratory disease and cancer. Sm oking 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 m achin ing asbestos containing friction materials. 3 DO NOT USE AN AIR HOSE FOR CLEANING 4 F M S I03488 SUM M ARY 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 live micrometers, per cubic centimeter. b. Ceiling (Peak) concentrations: Ten fibers, longer than five micrometers, per cubic centimeter. Engineering controls such a s isolation, enclosure, exhaust ventila tion and dust collection are the preferred m ethods for meeting the prescribed exposure limits. All external surfaces m ust be m ain 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 room s and employee notification are required where asbestos fiber concen trations exceed permissible exposure limits. The standard re quires that all workplaces where asbestos fibers m ay be released shall be monitored to determine exposure levels, and regular monitoring is required where exposure levels are expected to exceed permissible limits. Em ployers m ust maintain records of monitoring required by the standard. They m ust also provide or make available medical examinations for employees exposed to airborne concentrations of asbestos fibers. 5 rw sio s 89 ir USE VACUUM OR WET METHODS FOR CLEANING FMSI 03490 TT HANDLING NEW FRICTION MATERIALS Handling new disc brake assemblies, lined 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 purchased in bulk quantities, abrasion during shipm ent may result in the accumulation of dust in shipping containers. Dust should be removed by vacuum ing or cleaning with a dam p cloth. Whenever possible, purchase friction materials preground and ready for installation. This may keep dust levels below O SH A m axim um s and eliminate the need for respiratory protection, restricted areas, regular monitoring, special clothing, change room s and employee notification. , REMOVING WORN FRICTION MATERIALS Asbestos fibers in disc brake linings, drum brake linings, blocks and dry clutch facings are locked into the product with resin binders which prevent the release of asbestos fiber during normal installation. Heat and abrasion during normal use m ay generate dust containing asbestos. Some dust will accumulate in brake and clutch assemblies. W hen removing worn friction materials, remove the accumulated d ust in the a sse m b lie s with an industrial vacuu m cleaner equipped with a high efficiency filter system. If such equipment is not available, dust can be removed with a dam p cloth. Do not use com pressed air or dry brushing for cleaning. U se a N IO SH approved respirator when removing worn friction materials, or cleaning brake or clutch assemblies. M A CH IN IN G FRICTION MATERIALS There is an increasing trend for manufacturers and rebuilders to provide brake lining and clutch facings pre-drilled and pre-ground in final assem bly form. In the case of truck brake blocks, various oversize thicknesses are available. However, there are som e instances where field m achining is necessary. This is particularly true for construction and industrial equipment applications which m ay require m achining 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. W henever possible friction materials sh ou ld be cut to length with a shear rather than a saw or abrasive cut-off wheel. 7 FM S I03491 T DO NOT SWEEP IN WORK AREA - USE VACUUM METHOD FM SI03492 v D U ST COLLECTION METHODS W hen 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 adequate dust controls are employed. The preferred method for m inim izing airborne dust from m achining 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 am ounts of airborne asbestos fiber are arc grinding and beveling of lined brake shoes and linings or brake blocks. Grinding m achines used for these operations m ust be provided with exhaust ventilation to maintain worker exposures within permissible levels. It a central exhaust system is not available. N IO SH (National Institute for Occupational Safety and Health) has stated that, at a miminum, the dust bag of the arcing m achine shall be removed and replaced with the hose from a high efficiency industrial vacuum. For large volume m achining operations that operate on a con tinuous basis, the preferred dust collection device is a fabric filter or baghouse. with a heavy-duty exhaust fan as the suction source. The dust collector m ust meet the air-cleaning requirements of the Federal Environmental Protection Agency Em ission Standard for Asbestos. Approval m ust be obtained from EPA for installation and operation of each system. OTHER M ETH O DS OF M IN IM IZIN G 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 sig n s a s follows: Asbestos Dust Hazard Avoid Breathing Dust Wear Assigned Protective Equipment Do Not Rem ain In Area Unless Your Work Requires It Breathing Asbestos Dust May Be Hazardous To Your Health 9 FMSI 03493 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 rem oving accum ulations of asbestos dust and waste. Never use com pressed air or dry sweeping for cleaning. Water or other dust suppressants should be applied if brooms are used. Good personal hygiene practices are important in minimizing asbestos dust exposure. Do not smoke. W ash before eating. Showe r after work. C hange to work clothes upon arrival at work and change from work clothes at conclusion of work. W ork clothing 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 M ATERIAL D U ST 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 U se a N IO SH approved respirator w hen servicing vacuum cleaners, dust collectors, or handling any asbestos-containing waste materials. Asbestos-containing waste materials m ust be collected, process ed. packaged, transported and deposited in su ch fashion that no visible em issions are generated to the atmosphere. All wastes m ust be d isp osed of at sites operated in acco rd ance with applicable laws and regulations. li FMSf 03495 ir SOURCES OF ADDITIONAL INFORMATION ? * o 1 o i ) 0f O S H A * * * * * * * b* * , * 0 u **" i <-:cKle * Federal Regulations. Title 29. 'N ational Em ission* Standard* tor Hazardous M r Pollutants-- A t beato* and Mercury" (Code of Federal Regulations Title 40, Chapter 1. Subchapter C Part 61 Subparts A. B ) - EPA ' Fundamentals Governing the Design and Operation of lo ca l Erfreust Systems." A N S I 29.2 1971 0 7 .0 0 ) and "Practice* for Respiratory Protection." A N S I Z88 2- l % 9 ($5.50)-- ANSI ' "Industrial Ventilation M anuel" ($8.00)-- ACGIH f or d het inlormation, a user m ay contact the manufacturer supplying his friction materials, the Asbestos Inlormation Association or the Friction Materials Stand ards Institute. ACGIH American Conference ol Governmental Induslrial Hygienists Committee on Industrial Ventilation P.O.Bo 16153 Lansing. M l 48901 ANSI American National Standards Institute 14 30 Broadway New York. NY 10018 AIA Asbestos Inlormation Association 1745 Jelterson Davis Highway Arlington. VA 22202 EPA Environmental Protection Agency Public Inlormation Center 01 M Street SW Washington, D C 20460 FMSI Friction Materials Standards Institute East 2 10 Route 4 Paramos. NJ 07652 OSHA Occupational Safety and Heallh Administration Office of Information Washington. DC 20210 October 1978 F M S I03496 t IT