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What Is Considered a Dangerous Level of Asbestos Exposure?

Asbestos is a naturally occurring mineral. Before 1972, these versatile fibers were used mostly in building materials and in friction products such as brakes and clutches. Asbestos quickly lost its allure when it was found to be a health hazard.

  1. History

    • According to the World Health Organization, more than 125 million people in the world are exposed to asbestos in the workplace. Heaviest exposures occur when workers are removing the asbestos, but they can also be exposed when making products that contain asbestos.

    Hazards

    • Asbestos exposure can result in two main types of cancer: lung cancer and mesothelioma, a cancer of the thin membrane that surrounds the lung and other internal organs.

    Time-Weighted Average

    • The U.S. Occupational Safety and Health Administration has developed two main exposure limit guidelines. The first is time-weighted average: "The employer shall ensure that no employee is exposed to an airborne concentration of asbestos in excess of 0.1 fiber per cubic centimeter of (1 f/cc) as averaged over an 8-hour TWA day."

    Excursion Limit

    • OSHA's second exposure guideline is the excursion limit: "The employer shall ensure that no employee is exposed to an airborne concentration of asbestos in excess of 1.0 fiber per cubic centimeter of air (0.1 f/cc) as averaged over a sampling period of 30 minutes."

    Containment

    • OSHA has been regulating asbestos exposure since 1972, so now there are fewer asbestos-containing products being manufactured and marketed.

    Warnings

    • According to the World Health Organization, there are no known safe levels of asbestos because "a threshold is not known to exist."

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