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What Is Asbestos?

Friday, June 12, 2015
What Is Asbestos?

*Updated January 12, 2021

The dreaded "A" word: Asbestos. What we once thought of as a miracle mineral is now a dangerous nuisance. Although asbestos usage mostly halted in the late 1970s, individuals still run the risk of exposure, particularly in schools, hospitals, old homes, factories, and commercial buildings. Read on to learn more about asbestos and how 1Source can help you to protect your employees.

What Is Asbestos?

Asbestos is a category of fibrous mineral which includes six extremely durable and fire-, chemical-, electricity- and corrosion-resistant minerals. The most common form is chrysotile. The other minerals include amosite, crocidolite, tremolite, anthophyllite and actinolite. According to the Environmental Protection Agency (EPA), these minerals occur naturally in rock and soil.

The strength of asbestos, along with its durability and heat resistance, made it the material of choice in roofing shingles, floor tiles, ceiling materials, textile products, car brakes and clutches. It's an effective insulator and is also used to strengthen products such as cloth, paper, cement and plastic. It also contaminates other building materials. For example, vermiculite, another common mineral used in insulation, may contain asbestos. More than 70% of vermiculite sold in the United States between 1919 and 1990 came from a single mine containing an asbestos deposit.

Asbestos exposure is directly linked to many lung and respiratory health conditions. All types of asbestos are known carcinogens. Inhaling or ingesting the fibers may leave them trapped in the body for decades. The first symptoms of exposure usually occur 20 to 50 years later.

Despite its health concerns, the use of asbestos is not outright banned. It's banned in certain products, which may release asbestos fibers during use. Many manufacturers have also stopped using asbestos in their products without an official law. The EPA banned all new uses of asbestos in 1989, while existing uses are still allowed. It's more likely to be found in buildings constructed in the 1970s or earlier. Today, the substance is highly regulated by both the EPA and the Occupational Safety and Health Administration (OSHA).

Serpentine Aspestos vs. Amphibole Asbestos

The six types of asbestos minerals break into two categories — serpentine and amphibole — based on their physical characteristics. Identifying it requires a microscope and an analysis of the crystal structures. Both types are hazardous, and any exposure may have adverse health consequences.

Serpentine Asbestos

Serpentine asbestos has curly fibers, which develop in a layered or tiered configuration. Chrysotile, the most common form of asbestos, is the only serpentine asbestos. This type is highly regulated but still allowed in many uses. While it is sometimes considered the less toxic form, it should be treated with the same level of caution as amphibole, especially since it's so common. Also, natural chrysotile deposits may contain trace amounts of amphibole asbestos, which increases its toxicity.

Some serpentine chrysotile products include:

  • Adhesives
  • Drywall
  • Fireproofing
  • Gaskets
  • Brake pads
  • Cement
  • Insulation
  • Vinyl tiles
  • Roofing

Amphibole Asbestos

Amphibole asbestos has needle-shaped jagged fibers and a chain-like structure. Since amphiboles remain in the lung for longer periods, they are even more toxic than the serpentine variety. Exposure to amphibole asbestos is associated with a higher risk of mesothelioma than the same amount of exposure to chrysotile.

All other types of asbestos minerals fall into the amphibole category, including:

  • Amosite: Right after chrysotile, amosite is the most-often used form of asbestos. It's commonly found in insulation products, cement sheets, gaskets, roofing materials, vinyl tiles and fire protection products.
  • Crocidolite: Crocidolite is the most dangerous form of asbestos. Because the fibers are so thin, they are more easily lodged in lung tissue. The material has been used in fireproofing materials, insulation, ceiling tiles and cement sheets.
  • Tremolite: Tremolite doesn't have any commercial uses. It can be found in trace amounts of other materials, including chrysotile, vermiculite and talc.
  • Anthophyllite: While it has occasionally been used in construction products, anthophyllite is rare. It has been used in cement, insulation, roofing and rubber products. Like tremolite, it's also a common contaminant in vermiculite and talc.
  • Actinolite: While not usually used for commercial products, actinolite is another common incidental contaminant in other products. It has been found in paints, sealants and more.

Diseases Related to Asbestos

When asbestos is disturbed and becomes airborne, people nearby inhale the fibers, which become trapped in the lungs. Over time, the fibers accumulate and cause scarring and inflammation, which affects breathing. It can also cause health issues after ingestion, such as drinking water from an asbestos cement pipe.

The mineral leads to serious health problems like:

  • Mesothelioma: Asbestos and mesothelioma are scientifically linked. A rare form of cancer affecting the linings of the chest and abdomen, mesothelioma lung cancer is almost exclusively associated with workplace asbestos exposure. All forms of asbestos pose this risk. Family members of exposed employees and people who live near asbestos mines and factories are also at greater risk for mesothelioma. While any amount of exposure poses a threat, it increases with higher exposures. Mesothelioma takes a long time to develop and typically gets diagnosed 30 years or more after the first exposure.
  • Lung cancer: Asbestos exposure has a cancer risk for many types of cancers. Lung cancer is a common and usually fatal disease associated with asbestos. All forms of asbestos may cause lung cancer, which typically surfaces at least 15 years after the first exposure. The more exposure that occurs, the higher the risk. Lung cancer risks increase dramatically with the combination of smoking and asbestos exposure. The threat is even greater than the two individual risks added together.
  • Asbestosis: The risk of asbestosis, a lung disease, is also associated with asbestos. A type of pulmonary fibrosis, the condition involves scarred lung tissue. It may take up to 20 years to develop.
  • Asbestos can also cause ovarian or testicular cancer, laryngeal cancer and problems with the lining around the lungs.

Asbestos in the Workplace

Asbestos exposures in the workplace are the most significant risk factor for asbestos-related diseases. While it was once more widespread than today, it's still usually encountered in occupational settings.

Most At-Risk Workplaces

Asbestos exposures can happen almost anywhere. Even offices and commercial buildings may pose a threat if the construction includes any asbestos-containing building materials.

Some of the most at-risk workplaces include:

  • Construction sites: Throughout the 20th century, 70%-80% of all asbestos products were used in the construction industry. Since the material is commonly found in insulation and building materials, construction workers are at high risk for exposure. The danger increases in workplaces that renovate older buildings.
  • Shipyards: Asbestos is a common material found in older ships, especially for pipe coverings, insulation, gaskets and valves. When shipyard workers deconstruct or perform repairs on older vessels, they may disturb the material. The risk increases because the work involves being in tight quarters.
  • Manufacturing facilities: Manufacturers of textiles, friction products, insulation and other materials that contain asbestos put their employees at risk.
  • Automotive repair shops: Mechanics involved in brake and clutch repair work can release asbestos during their work.

OSHA Regulations

OSHA has asbestos regulations for general industry, which you can find in the 29 CFR 1910.1001 standard. The administration also has specific rules for maritime workplaces, contained in the 29 CFR 1915.1001 standard. In the construction industry, you can refer to the 29 CFR 1926.1101 standard. The regulations include a maximum level of legally allowable exposure. Many states have an OSHA-approved state plan covering private and public workers.

The general industry standard requires employers to:

  • Assess the workplace or construction site before work begins to determine how much asbestos exposure is possible.
  • Monitor the workplace to determine if exposure increases above the maximum allowable level.
  • Place signage where asbestos work is performed.
  • Set up decontamination areas with proper hygiene practices and keep them separate from employee lunch areas.
  • Conduct training before exposure and yearly refresher courses for workers exposed to asbestos.
  • Provide medical surveillance as needed within the industry, which generally includes making medical examinations available to exposed workers.
  • Maintain records for asbestos exposure for at least 30 years.
  • Maintain medical surveillance records for each exposed employee through the duration of employment and for 30 years after.

Rights of Workers

Workers have several rights concerning asbestos exposure. According to OSHA, workers who may be exposed to asbestos have the right to:
  • Receive training related to workplace asbestos hazards and relevant OSHA standards in a language they understand.
  • Receive and wear safety gear and personal protective equipment (PPE) to limit the hazards of asbestos.
  • Review workplace records of illnesses and injuries.
  • See asbestos test and assessment results.
  • File a complaint with OSHA and request an inspection to assess asbestos exposure or other safety hazards.
  • Remain confidential when filing an OSHA complaint and exercise their rights without fear of retaliation.

Legal Ramifications

In general, asbestos-related diseases are handled through workers' compensation claims. This route is an exclusive remedy, meaning the employee or former employee may not sue the employer if they receive compensation. The employee may sue the original manufacturer of the asbestos product for additional compensation. If the company does not cover asbestos exposures in its workers' compensation package, the employee can sue the employer.

One complication is the liability for secondary asbestos exposure. An employer's legal responsibility for others who develop illnesses after exposure to the worker is complicated. The legal ramifications depend on the state, and asbestos laws are still evolving.

Conducting a Facility Asbestos Survey

A facility asbestos survey and investigation is essential to identify and assess asbestos materials during the early planning of a renovation project. What is an asbestos test, and what is it used for? The process produces a survey report, a tool to use for the operations and maintenance program, hazard communication, coordinating with contractors and planning renovations.

An EPA-certified and state-licensed asbestos building inspector should complete the survey and identify all asbestos-containing materials. Friable materials, or materials that crumble easily, pose the highest risk. Friable materials include pipe insulation, fittings, tank insulation, fireproofing and acoustic plaster. During construction and renovations, nonfriable materials should also be inspected, especially if the project involves drilling, sawing or a chance the materials could break. Nonfriable materials include floor tiles, mastic, transite panels and exterior siding.

The inspector will take detailed samples of any building materials which may contain asbestos. Some of those samples are required under the Uniform Building Code based on construction dates and later renovations. They will also consider the planned renovations and demolitions and any areas of concern. The inspector will determine the quantities and conditions of accessible asbestos materials and note if there might be concealed asbestos materials above ceilings, in pipe chases, under carpets or elsewhere.

Frequently Asked Questions About Asbestos

At 1Source Safety and Health, we get many questions about asbestos. It's a notoriously toxic substance, and when there's a potential for workplace exposure, you want to take control over the situation. Our experienced experts have the answers to your top questions.

What Is Asbestos Made of?

Asbestos is a naturally occurring mineral that grows in soil and on rocks, sometimes alongside other minerals like talc and vermiculite. It grows in long, thin fibrous crystals, which stick together to form larger masses. Asbestos deposits are extracted in open-pit mines. Most deposits contain 5%-6% asbestos, with some containing up to 50% concentrations. When it's first extracted, it looks like old wood. When it is refined, it looks fluffy and fibrous. The U.S. mined asbestos in the late 1800s through the 20th century — including in some mines in Pennsylvania and Maryland — but now imports it.

What Color Is Asbestos?

Asbestos comes in many colors but is typically white. Chrysotile also goes by the name "white asbestos." The two other main color varieties are brown asbestos, or amosite, and blue asbestos, or crocidolite. Here's how you can recognize the coloration and appearance of each type of asbestos:
  • Chrysotile: Known as "white asbestos," chrysotile has white, curly fibers that give it a cotton-like or gauze-like appearance.
  • Amosite: Dubbed "brown asbestos," amosite has straight brown fibers. The coloration comes from its iron content.
  • Crocidolite: Also called "blue asbestos," crocidolite appears blue thanks to its high sodium content combined with traces of magnesium and iron. It also appears yellow or dark gray, depending on its origin and processing.
  • Tremolite: Tremolite appears brown, gray, white or green and may even be translucent.
  • Anthophyllite: Anthophyllite ranges from gray to white to brown.
  • Actinolite: Actinolite's iron content produces a distinctive dark green. The mineral grows in formations ranging from fibrous masses to quartz-like crystals. These qualities make it valuable as a gemstone when it forms solid, nonfibrous crystals.

What Amount of Asbestos Exposure Is Dangerous?

The short answer is that any amount of asbestos exposure is dangerous. In high concentrations or over prolonged periods, it becomes even more hazardous. OSHA sets a permissible exposure limit (PEL) for asbestos in the workplace, at 0.1 fiber per cubic centimeter over an 8-hour time-weighted average (TWA). While maintaining this concentration lowers the risk, the agency still considers exposures below this level dangerous.

It's critical to note that the airborne fibers are what pose a threat. Materials containing asbestos aren't considered harmful until they release fibers into the air when manipulated or disturbed. Employees who may contact asbestos materials but will not intentionally disturb the materials should receive Asbestos Awareness Training. The training should include recognizing asbestos-containing materials, hazards of exposures, and procedures to follow after encountering damaged materials.

What Is the Flame Spread Rating of Asbestos?

One of the reasons asbestos is a popular building material is its excellent flame spread rating. Cement asbestos has a flame spread rating of zero, alongside a smoke developed rating of zero. The ASTM E84 flame spread rating test actually uses cement asbestos as its control material. It receives an automatic zero to compare it with other materials. Asbestos is used in fireproofing materials and has a Class A fire rating.

What Should I Do If Asbestos Is Disturbed?

Disturbing asbestos, which releases its fibers into the air, creates the risk of respiratory diseases. If you discover asbestos on the job, stop immediately and put up appropriate signage to keep others from entering the area. If the material is accidentally disturbed during work, stop work immediately and act fast to begin safe cleanup.

Evacuate the area. Anyone who has dust or debris on clothing should stay as still as possible and get help putting on respiratory protective equipment (RPE). Prevent access to the area and seek to stop the spread of the fibers in the air. Anyone exposed to the dust should wipe down clothing with damp rags.

Finally, seek help from an asbestos specialist like 1Source to survey the risk level and recommend actions for making the area safe. If the discovered materials could be disturbed again during renovation or other activities, they must be removed. 1Source will work with you and the project architect or engineer to define the scope of work for removal, develop removal specifications and help select qualified and licensed contractors.

What Is Asbestos Abatement?

Asbestos abatement involves removing asbestos and mitigating the associated risks. Sometimes, abatement involves sealing it off rather than removal. Abatement starts with inspecting the area, marking off the asbestos hazards and informing building occupants to leave until the process is complete. Asbestos removal can only be conducted inside a "regulated area." The regulated area is sealed with polyethylene sheets sealed with tape.

Caution signs are placed at the entrances to warn people that asbestos fibers may be released inside the containment. HVAC systems are sealed to prevent the dispersal of fibers throughout the building.

1Source will monitor removal projects and conduct visual inspections and air sampling to verify that fibers are not released from the regulated area.

Learn More for Professional Safety and Health Professionals

The 1Source team has experienced health and safety professionals, industrial hygiene technicians and asbestos specialists ready to help you plan and safely execute your project. We have asbestos-related licenses and certifications from the EPA and the states of Pennsylvania, Delaware, Maryland, New Jersey, Virginia and West Virginia.

Our consultations for managing asbestos can give you clear direction and answers to your workplace's pressing asbestos concerns. For more information about common workplace hazards like asbestos, sign up for The Risk Factor Newsletter.

Have more questions about asbestos? Contact Chris Schneider, CIH, at 610-524-5525 x14 or request a quote and more information on our asbestos consulting services.