Asbestos is a term that describes a fiber that is a component of six naturally-occurring minerals. Chrysotile, the fibrous form of the mineral serpentine, is the best-known mineral type and accounts for about 95 percent (%) of all asbestos in commercial use. When milled, asbestos has had many uses because of its resistance to heat and corrosion, and its tensile strength. Because of these characteristics, asbestos was used in numerous building materials and vehicle products.
However, beginning in the 1970’s, reports of the harmful effects of asbestos fibers on human health caused increasing concern. Individual asbestos fibers cannot be seen with the naked eye and can be released into the air during activities that disturb asbestos-containing materials (ACMs). When airborne, the asbestos fibers can unknowingly be inhaled and trapped in the lungs, or incidentally ingested and trapped in the digestive system. The resulting adverse effects on human health include asbestosis (or scarring of the lung tissue), mesothelioma (a rapidly fatal form of lung cancer), and colon cancer, identifying asbestos as a known human carcinogen. Following exposure to asbestos, symptoms and/or cancer may take many years to develop.
Once these health risks were firmly documented in the 1970s, regulatory agencies in the United States (U.S.) and other developed nations began placing tight restrictions on workers’ exposure to asbestos in industrial plants. These U.S. agencies include the U.S. Environmental Protection Agency (EPA) and the Occupational Health and Safety Administration (OSHA). State and local agencies may also have specific rules and regulations applicable to identifying and working with ACMs. The U.S. EPA defines ACM as any material containing greater than 1% asbestos. Because the health impacts from asbestos are now well known, a risk and hazard assessment as well as proper mitigation should be included in your job or task specific health and safety plan and in your Job Safety Analysis (JSA).
On July 12, 1989, the U.S. EPA issued a final rule under Section 6 of the Toxic Substances Control Act (TSCA) instituting a gradual ban on the manufacture, use, and export of most asbestos-containing products in the U.S. In 1991, the rule was vacated and remanded by the Fifth Circuit Court of Appeals. As a result, most of the original ban on the manufacture, importation, processing, or distribution in commerce for most of the asbestos-containing product categories originally covered in the 1989 final rule was overturned. Only the bans on corrugated paper, rollboard, commercial paper, specialty paper, and flooring felt, and any new uses of asbestos remained banned under the 1989 rule. Although most asbestos-containing products can still legally be manufactured, imported, processed, and distributed in the U.S., according to the U.S. Geological Survey, the production and use of asbestos has declined significantly.
Some materials are presumed to contain asbestos if installed before 1981 and should be evaluated in the Job Safety Analysis or Job Hazard Analysis (JHA). Examples of these materials and other presumed ACMs include:
- Roofing and siding shingles
- Thermal system insulation, such as vermiculite insulation
- Plaster, cement, putties, and caulks
- Industrial pipe wrapping
- Ceiling tiles and spray-on coatings (such as “popcorn” ceilings)
- Vinyl floor tiles, including the mastic used to affix the tiles
- Automobile brake linings and clutch pads
Differences between dangerous and safe ACMs in the materials previously listed include the legal definitions of “friable” and “non-friable” asbestos. “Friable” ACM is any material that contains more than 1% asbestos by weight or area, depending on whether it is a sheet or bulk material, and can be crumbled, pulverized, or reduced to powder by the pressure of an ordinary human hand. “Non-friable” ACM is any material that contains more than 1% asbestos, but cannot be pulverized by the pressure of an ordinary human hand.
To further complicate the legal definitions are the following two classifications of “non-friable” ACM:
- Category I non-friable ACM includes asbestos gaskets, packings, resilient floor coverings, and asphalt roofing products.
- Category II is any non-friable ACM not included in Category I.
The legal definition of “Regulated Asbestos-Containing Materials” (RACMs) includes the following:
- All friable ACMs.
- Any Category I non-friable ACMs that have become friable as the other materials in them have broken down with weathering or age.
- Any Category II non-friable ACMs that have a high probability of becoming or have become crumbled, pulverized, or powdered by the forces to act on the material during demolition or renovation operations.
Any ACM can become friable and fall under federal regulations. When non-friable ACM becomes friable, it is the building material in which it was used that crumbles, not the asbestos itself. As the clay or other minerals in the building materials age or wear, they break down and release the more durable asbestos fibers. Burning any non-friable ACM can also release asbestos fibers and change the classification to friable and regulated. Any activities that involve cutting, grinding, abrading, or drilling of non-friable ACM will release asbestos fibers thereby falling under federal regulations.
Suspect materials must be treated as ACM until sampling and analysis indicates that the material does not contain detectable asbestos. Samples should be taken by a properly trained and accredited asbestos professional (inspector), and the samples should be analyzed by an approved laboratory using prescribed methodologies. Only laboratory analysis can indicate whether a material contains asbestos, and should be subsequently handled/treated appropriately as ACM or non-ACM material.
The best approach to reducing or eliminating the health risks associated with ACM is to leave the material undisturbed. The risks from asbestos occur when it is damaged or disturbed where asbestos fibers become airborne and can be inhaled. Managing asbestos in place and maintaining it in good repair is often the best approach. A Job Safety Analysis discussion can help in determining the best approach for your specific situation.
OSHA has the following three standards to protect workers from any risks or hazards associated with ACM depending on the type of workplace.
- General Industry: 29 Code of Federal Regulations (CFR) 1910.1001 covers work in general industry, such as exposure during brake and clutch repair, maintenance work, and manufacture of asbestos-containing products.
- Shipyards: 29 CFR 1915.1001 covers construction, alteration, repair, maintenance, renovation, and demolition of structures containing asbestos during work in shipyards.
- Construction: 29 CFR 1926.1101 covers construction, alteration, repair, maintenance, or renovation and demolition of structures containing asbestos.
For complete information on all requirements within each specific standard, please review the standard specific to the workplace. The following are protections established for workers within these standards.
- The Permissible Exposure Limit (PEL) for asbestos is 0.1 fiber per cubic centimeter of air as an eight-hour time-weighted average (TWA), with an excursion limit (EL) of 1.0 asbestos fibers per cubic centimeter over a 30-minute period. The employer must ensure that no one is exposed above these limits.
- Assessment of workplaces covered by the standards must be completed to determine if asbestos is present and if the work will generate airborne fibers by a specific method under each standard.
- Monitoring necessary to detect if asbestos exposure is at or above the PEL or EL for workers who are, or may be expected to be exposed to asbestos. Frequency depends on work classification and exposure. The construction and shipyard standards require assessment and monitoring by a competent person.
- If the exposure has the potential to be above the PEL or EL, employers must use proper engineering controls and work practices to the extent feasible to keep it at or below the PEL and EL. Where feasible engineering controls and work practices do not ensure worker protection at the exposure limits, employers must reduce the exposures to the lowest level achievable and then supplement with proper respiratory protection to meet the PEL. The construction and shipyard standards contain specific control methods depending on work classification, and the general industry standard has specific controls for brake and clutch repair work.
- Proper hazard communication and demarcation with warning signs containing specified language in areas that have exposures above the PEL or EL is necessary. No smoking, eating, or drinking should occur in these areas, and proper PPE must be provided and used to prevent exposure.
- Separate decontamination and lunch areas with proper hygiene practices must be provided to workers exposed above the PEL to avoid contamination.
- Training requirements depend on the workplace exposure and classification. Training must be provided to all workers exposed at or above the PEL before work begins and yearly thereafter. All training must be conducted in a manner and language in which the worker is able to understand. Workers who perform housekeeping operations in buildings with presumed ACMs but not at the PEL must also be provided asbestos awareness training.
- Medical surveillance requirements are different depending on the industry. Medical surveillance must be provided for workers who engage in certain classifications of work, or experience exposures at or above the PEL in construction and shipyards. In general industry, medical examinations must be provided for workers who experience exposure at or above the PEL.
- Records must be kept on exposure monitoring for asbestos for at least 30 years, and worker medical surveillance records retained for the duration of employment plus 30 years. Training records must be kept for at least one year beyond the last date of employment.
JSABuilder is a state-of-the-art online job safety analysis app to assist in preparing your Job Hazard Analysis (JHA), Job Safety Analysis (JSA) or Activity Hazard Analysis (AHA). Set up a free trial account today and follow us on Twitter @JSABuilder, where we Tweet about Health and Safety, provide Safety tips, and updates on current Health and Safety topics.
Images, links, brands discussed or displayed in this article are not endorsements or recommendations. They are for illustration of various products and types of products. JSABuilder does not recommend or express any opinion as to the applicability to any given use case or job hazards.