What is asbestos?
Asbestos is the generic term for a group of naturally occurring, fibrous minerals with high tensile strength, flexibility, and resistance to heat, chemicals, and electricity.
In the construction industry, asbestos is found in installed products such as sprayed-on fireproofing, pipe insulation, floor tiles, cement pipe and sheet, roofing felts and shingles, ceiling tiles, fire-resistant drywall, drywall joint compounds, and acoustical products. Because very few asbestoscontaining products are being installed today, most worker exposures occur during the removal of asbestos and the renovation and maintenance of buildings and structures containing asbestos. What are the dangers of asbestos exposure?
Asbestos fibers enter the body when a person inhales or ingests airborne particles that become embedded in the tissues of the respiratory or digestive systems. Exposure to asbestos can cause disabling or fatal diseases such as asbestosis, an emphysema-like condition; lung cancer; mesothelioma, a cancerous tumor that spreads rapidly in the cells of membranes covering the lungs and body organs; and gastrointestinal cancer. The symptoms of these diseases generally do not appear for 20 or more years after initial exposure. What construction activities does this booklet cover?
The asbestos standard for the construction industry (29 CFR Part 1926.1101, see www.osha.gov) regulates asbestos exposure for the following activities:
- Demolishing or salvaging structures where asbestos is present.
- Removing or encapsulating asbestos-containing material (ACM).
- Constructing, altering, repairing, maintaining, or renovating asbestos-containing structures or substrates.
- Installing asbestos-containing products.
- Cleaning up asbestos spills/emergencies.
- Transporting, disposing, storing, containing, and housekeeping involving asbestos or asbestos-containing products on a construction site.
Note: The standard does not apply to asbestos-containing asphalt roof coatings, cements, and mastics. Provisions of the OSHA Standard
OSHA has established strict exposure limits and requirements for exposure assessment, medical surveillance, recordkeeping, competent persons, regulated areas, and hazard communication. What is work classification?
The OSHA standard establishes a classification system for asbestos construction work that spells out mandatory, simple, technological work practices that employers must follow to reduce worker exposures. Under this system, the following four classes of construction work are matched with increasingly stringent control requirements:
- Class I asbestos work is the most potentially hazardous class of asbestos jobs. This work involves the removal of asbestos-containing thermal system insulation and sprayed-on or troweled-on surfacing materials. Employers must presume that thermal system insulation and surfacing material found in pre-1981 construction is ACM. That presumption, however, is rebuttable. If you believe that the surfacing material or thermal system insulation is not ACM, the OSHA standard specifies the means that you must use to rebut that presumption. Thermal system insulation includes ACM applied to pipes, boilers, tanks, ducts, or other structural components to prevent heat loss or gain. Surfacing materials include decorative plaster on ceilings and walls; acoustical materials on decking, walls, and ceilings; and fireproofing on structural members.
- Class II work includes the removal of other types of ACM that are not thermal system insulation such as resilient flooring and roofing materials. Examples of Class II work include removal of asbestos-containing floor or ceiling tiles, siding, roofing, or transite panels.
- Class III asbestos work includes repair and maintenance operations where ACM or presumed ACM (PACM) are disturbed.
- Class IV work includes custodial activities where employees clean up asbestos-containing waste and debris produced by construction, maintenance, or repair activities. This work involves cleaning dust-contaminated surfaces, vacuuming contaminated carpets, mopping floors, and cleaning up
What is the permissible exposure limit for asbestos?
- ACM or PACM from thermal system insulation or surfacing material.
Employers must ensure that no employee is exposed to an airborne concentration of asbestos in excess of 0.1 f/cc as an 8-hour time-weighted average (TWA). In addition, employees must not be exposed to an airborne concentration of asbestos in excess of 1 f/cc as averaged over a sampling period of 30 minutes. Which asbestos operations must employers monitor and assess?
Employers must assess all asbestos operations for the potential to generate airborne fibers, and use exposure monitoring data to assess employee exposures. You must also designate a competent person
to help ensure the safety and health of your workers. What is the function of a competent person?
On all construction sites with asbestos operations, employers must designate a competent person
—one who can identify asbestos hazards in the workplace and has the authority to correct them. This person must be qualified and authorized to ensure worker safety and health as required by Subpart C, General Safety and Health Provisions for Construction
(29 CFR Part 1926.20). Under these requirements for safety and health prevention programs, the competent person must frequently inspect job sites, materials, and equipment.
The competent person
must attend a comprehensive training course for contractors and supervisors certified by the U.S. Environmental Protection Agency (EPA) or a state approved training provider, or a complete a course that is equivalent in length and content.
For Class III
asbestos work, training must include a course equivalent in length, stringency, and content to the 16-hour Operations and Maintenance
course developed by EPA for maintenance and custodial workers. For more specific information, see 40 CFR Part 763.92(a)(2)
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