OSHA Releases Proposed Rules on Respirable Crystalline Silica

In what promises to be one of the most controversial Occupational Safety and Health Administration (OSHA) rulemaking efforts in decades, last Friday, OSHA released two proposed rules aimed at protecting workers exposed to respirable crystalline silica -- one rule would regulate general industry and maritime employment and another would apply to construction. Both rules, according to OSHA, seek to curb lung cancer, silicosis, chronic obstructive pulmonary disease, and kidney disease among silica-exposed workers. These rules will affect work involving industrial sand, stone, concrete, rock, brick, block, and mortar in a broad range of industries, including hydraulic fracturing by the oil and gas industry, pottery manufacturing, foundries, and sand blasting.

The proposed rules would replace a 40-year old permissible exposure limit (PEL) of 100 micrograms per cubic meter(µg/µ³) by setting an action level of 25 µg/µ³ of silica as an eight-hour time-weighted average (TWA), with 50 µg/µ³ as the eight-hour TWA PEL. Exposures over the 25 µg/µ³ action level would require exposure monitoring and dust controls. If such controls are inadequate, employers would be required to limit workers' access to areas where they could be exposed to concentrations of crystalline silica above the PEL, use dust controls, provide employees with respiratory protection, offer medical exams (including chest X-rays and lung function tests) every three years for workers exposed above the PEL for 30 or more days per year, train exposed workers on ways to limit such exposures, and keep records of exposures and medical exams.

Under consideration by OSHA going back to the Clinton Administration, lowering of the PEL has been opposed by the business community as unnecessary and infeasible. On the other hand, lowering of the PEL has long been a priority of organized labor, notably the AFL-CIO. OSHA chief Dr. David Michaels stated in the agency's press release that the rule is expected to save nearly 700 lives and prevent 1,600 new cases of silicosis every year once the full effects of the rule are realized. The agency estimates that over 640,000 construction workers and 127,000 maritime and general industry workers are exposed above the proposed PEL.

The proposed rules will be published in the Federal Register soon, and OSHA will allow a comment period of 90 days from the date of publication. Public hearings on the proposal are set to begin in March 2014.