Proposed Silica Dust Rule to Limit Exposure on the Job

Forty-year-old caps on silica dust in construction and industry are to be slashed by OSHA.

The U.S. Occupational Safety and Health Administration (OSHA) is proposing more stringent exposure limits for crystalline silica—dust particles produced by cutting or crushing stone products and a known cause of lung cancer and silicosis. Heightened standards are projected to save nearly 700 lives and prevent 1,600 new cases of silicosis per year, many in the construction or glass manufacturing industries.

OSHA’s proposed permissible exposure limit (PEL) is 50 μg/m³ (micrograms of silica per cubic meter of air) averaged over an eight-hour day—a significant cut from the current 40-year-old limits (100 μg for general and maritime industries and 250 μg in construction).

Companies also must supply respirators if controls fail to achieve the PEL and must offer medical exams to those working in these conditions for 30 days or more per year. Another major provision requires companies to measure airborne silica if levels are above 25 μg/m³; however, there are “flexible alternatives” for construction companies that institute certain dust control measures, such as using a stationary masonry saw equipped with a water delivery system.

The labor union for industrial organizations, AFL-CIO, welcomed the proposal as “long overdue” in a press release, but several members of the Construction Industry Safety Coalition, including the National Association of Home Builders (NAHB), are worried about practicality and cost.

According to a statement from NAHB, dust-capture systems are not appropriate in all applications (such as when spraying water could cause mold); the trade group also argues that the cost of compliance would be overly burdensome to the construction industry and would exceed $1 billion per year.

For more information:

Occupational Safety and Health Administration

https://www.osha.gov/silica/nprm.pdf