Evaluating and Controlling Exposure

Evaluating Exposure

Determinations of employee exposure shall be made from breathing zone air samples that are representative of the 8-hour TWA and 30-minute short-term exposures of each employee.

Medical surveillance

Medical surveillance guidance is provided in the following appendices to the OSHA Standards:

• General Industry
  • 29 CFR 1910.1001 - Appendix D. Medical questionnaires; Mandatory.
  • 29 CFR 1910.1001 - Appendix E. Interpretation and classification of chest roentgenograms; Mandatory.
  • 29 CFR 1910.1001 - Appendix H. Medical surveillance guidelines for asbestos; Non-mandatory.
• Shipyard Employment
  • 29 CFR 1915.1001 - Appendix D. Medical questionnaires; Mandatory
  • 29 CFR 1915.1001 - Appendix E. Interpretation and classification of chest roentgenograms (x-ray); Mandatory.
  • 29 CFR 1915.1001 - Appendix I. Medical surveillance guidelines for asbestos; Non-mandatory.

Exposure monitoring

Exposure monitoring samples must be analyzed by Phase Contrast Microscopy (PCM) for OSHA purposes. PCM methods accurately assess fiber exposure levels, but PCM can not differentiate between asbestos and non-asbestos fibers. Transmission Electron Microscopy (TEM) methods may be used to identify fibers, but may not be used to quantify air concentrations for occupational exposure.

• OSHA Occupational Chemical Database. OSHA's premier one-stop shop for occupational chemical information. It compiles information from several government agencies and organizations. Information available on the pages includes chemical identification and physical properties, exposure limits, sampling information, and additional resources.
  • Asbestos, All Forms
• OSHA reference method; Mandatory (General Industry). OSHA Standard, 29 CFR 1910.1001 Appendix A.
• OSHA reference method; Mandatory (Shipyard Employment). OSHA Standard, 29 CFR 1915.1001 Appendix A.
• Detailed procedure for asbestos sampling and analysis; Non-mandatory (General Industry). OSHA Standard, 29 CFR 1910.1001 Appendix B.
• Detailed procedure for asbestos sampling and analysis; Non-mandatory (Shipyard Employment). OSHA Standard, 29 CFR 1915.1001 Appendix B

Analytical Methods

OSHA

OSHA has developed and validated methods for use by the Salt Lake Technical Center (SLTC) laboratory. The following method has been adopted by many laboratories for the analysis of chemical compounds. Exposures should be evaluated with standard total dust sampling techniques for comparison to the OSHA permissible exposure limits (PEL).

• Asbestos in Air. Method ID-160, (July 1997).
• Polarized Light Microscopy of Asbestos. Method ID-191, (Revised December 1992). See Bulk sample analysis.

National Institute for Occupational Safety and Health (NIOSH)

• NIOSH Manual of Analytical Methods (NMAM). NMAM is a collection of methods for sampling and analysis of contaminants in workplace air, and in the blood and urine of workers who are occupationally exposed. NMAM also includes chapters on quality assurance, sampling, portable instrumentation, etc.
  • Asbestos and Other Fibers by PCM. Method No. 7400, (August 15, 1994). A PCM procedure, equivalent to the OSHA methods.
  • Asbestos fibers by TEM. Method No. 7402, (August 15, 1994). Uses TEM to identify fibers (OSHA will accept this TEM procedure, as it uses PCM to determine exposure).
  • Asbestos, Chrysotile by XRD. Method No. 9000, (August 15, 1994).
  • Asbestos (bulk) by PLM. Method No. 9002, (August 15, 1994).

Bulk sample analysis

Bulk sample analysis should be done by Polarized Light Microscopy (PLM). Bulk analysis results will likely apply to both OSHA and EPA regulations.

• Polarized Light Microscopy of Asbestos. Method ID-191, (Revised December 1992). Describes the collection and analysis of asbestos bulk materials by light microscopy techniques including phase-polar illumination and central-stop dispersion microscopy.
• Polarized light microscopy of asbestos; Non-mandatory (General Industry). OSHA Standard, 29 CFR 1910.1001 Appendix J.
• Polarized light microscopy of asbestos; Non-mandatory (Shipyard Employment). OSHA Standard, 29 CFR 1915.1001 Appendix K.
• Directory of Accredited Laboratories. National Voluntary Laboratory Accreditation Program (NVLAP), (September 22, 2011). Includes online searchable directory. This accreditation is required for analyses being performed in compliance with AHERA regulations.

Other

• Sampling and Analysis of Multi-Layered Materials
  • Compliance with OSHA's Asbestos Standard - Composite Bulk Samples. OSHA Letter of Interpretation, (February 7, 1997).

Controlling Exposure

Controlling the exposure to asbestos can be done through engineering controls, administrative actions, and personal protective equipment (PPE). Engineering controls include such things as isolating the source and using ventilation systems. Administrative actions include limiting the workers exposure time and providing showers. Personal protective equipment include wearing the proper respiratory protection and clothing. The following resources contain information to help control asbestos exposures.

• NIOSH Pocket Guide to Chemical Hazards. U.S. Department of Health and Human Services (DHHS), National Institute for Occupational Safety and Health (NIOSH) Publication No. 2005-149, (September 2007). Provides a physical description, exposure limits, measurement method, personal protection and sanitation, first aid, respirator recommendations, exposure routes, symptoms, target organs, and cancer sites.
  • Asbestos
• Occupational Health Guidelines for Chemical Hazards. U.S. Department of Health and Human Services (DHHS), National Institute for Occupational Safety and Health (NIOSH) Publication No. 81-123, (January 1981). Contains information on identification, physical and chemical properties, health hazards, exposure limits, exposure sources and control methods, monitoring, personal hygiene, storage, spills and leaks, and personal protective equipment

Automotive

Precautions to prevent exposure to asbestos in friction products (brakes and clutches).

• Work practices and engineering controls for automotive brake and clutch inspection, disassembly, repair and assembly; Mandatory. OSHA Standard, 29 CFR 1910.1001 Appendix F.
• Asbestos-Automotive Brake and Clutch Repair Work. OSHA Safety and Health Information Bulletin (SHIB), (July 26, 2006).
• Concerns About Asbestos Exposure for Mechanics. Environmental Protection Agency (EPA). Examines exposure opportunities among auto mechanics involved with brake linings, clutch facings, and other friction materials. [References Current Best Practices for Preventing Asbestos Exposure Among Brake and Clutch Repair Workers, (April 2007)].
• Control of Asbestos Exposure During Brake Drum Service. U.S. Department of Health and Human Services (DHHS), National Institute for Occupational Safety and Health (NIOSH) Publication No. 89-121, (August 1989). Presents recommendations for engineering controls and work practices to reduce exposure to asbestos during brake maintenance operations.
  • Asbestos Exposure During Servicing of Motor Vehicle Brake and Clutch Assemblies. Publication No. 78-127, (August 8, 1975). Offers procedures to control asbestos exposure.

Facilities

Operations and maintenance (O&M) practices are used to control hazards of asbestos.

• Smoking cessation program information for asbestos; Non-mandatory. OSHA Standard, 29 CFR 1910.1001 Appendix I. Includes contact information for organizations that provide smoking cessation information and program material.
• Managing Asbestos In Place, A Building Owner's Guide to Operations and Maintenance Programs for Asbestos-Containing Materials (Green Book). Environmental Protection Agency (EPA), (July 1990).
• Asbestos Operations and Maintenance Program Online. Virginia Tech, Environmental, Health and Safety Services. Provides standard work practices and procedures including education and training, occupant awareness, building surveys, inspections and hazards, exposure monitoring, recordkeeping and management.

Other

• Applicability Determination Index (ADI). Environmental Protection Agency (EPA). Enables the user to query the database of National Emissions Standards for Hazardous Air Pollutants (NESHAP) which includes "regulatory interpretations". Enter keyword "Asbestos".
• Protect Your Family. Environmental Protection Agency (EPA). Provides EPA guidance for home owners and their families.