Thought Leadership

On March 25, the Occupational Safety and Health Administration (OSHA) published a final rule establishing a new permissible exposure limit (PEL) for respirable crystalline silica of 50 micrograms per cubic meter of air, averaged over an eight-hour shift. According to OSHA, industries and operations in which exposure may occur include, among others, construction, foundries, jewelry production, ready-mix concrete, cut stone and stone products, railroad track maintenance, hydraulic fracturing for oil and gas production, and abrasive blasting. 

This final rule has been a long time in the making. Employer requirements pertain to exposure assessment, exposure control, respiratory protection, medical surveillance, hazard communication and recordkeeping. OSHA estimates 2 million construction workers and as many as 300,000 workers in general industry operations are exposed to respirable crystalline silica. 

The final rule establishes two separate standards: one for general industry and maritime and one for construction. Key provisions of the final rule require:

• use of engineering controls, such as water misting or ventilation of work spaces, to limit worker exposure to the PEL;
• provision of respirators to affected workers, if engineering controls cannot adequately limit exposure to the PEL;
• development of a written respirable crystalline silica exposure control plan, which describes the identification and control of workplace exposures;
• offer of medical exams to certain workers who will be exposed at or above the action level of 25 micrograms per cubic meter (general industry and maritime) or are required to wear a respirator under the construction standard for 30 or more days per year; and
• training of workers on the risks of respirable crystalline silica and methods for limiting exposure.

OSHA's final rule takes effect June 23. While the final rule sets forth a more detailed compliance schedule, in general, affected employers must comply with the final rule as follows:

• Construction: June 23, 2017
• General Industry and Maritime: June 23, 2018
• Hydraulic Fracturing: June 23, 2018 (except for the engineering controls provisions, which have a compliance date of June 23, 2021)