On Friday, March 25, 2016, the Occupational Safety and Health Administration (OSHA) published a final rule reducing the permissible exposure limit (PEL) to respirable crystalline silica (RCS), reducing the PEL to 50 micrograms of respirable crystalline silica per cubic meter of air (μg/m3) averaged over an 8-hour day (8-hr TWA). The PEL applies to all forms of RCS in all industry sectors, which OSHA characterizes as essentially a reduction of 50% of the current PELs for both the Construction and General Industry. Two separate standards were adopted, one for general industry and maritime in 29 C.F.R. § 1910.1053(l) and one for construction in 29 C. F. R. § 1926.1153(k). OSHA’s final rule also contains an action level of 25 µg/m3 per 8-hr TWA and requirements for exposure monitoring, engineering controls (such as wet methods or ventilation) and work practices to limit worker exposure, conducting routine medical examinations, and RCS-specific training.

OSHA had originally proposed the new PEL in its Notice of Proposed Rulemaking (NPRM) on occupational exposures to respirable crystalline silica, which was published on September 12, 2013. In the NPRM, OSHA claimed that a PEL reduction for RCS was needed to prevent an estimated 6 to 26 additional deaths from lung cancer, 43 additional deaths from silicosis, and 32 deaths from renal disease per 1,000 exposed employees, which OSHA determined using a conservative risk assessment on unprotected RCS exposures over a 45 year working lifetime (8 hours per day, 5 days per week, and 50 weeks per year for 45 years). In the final rule, OSHA estimates that the standard will prevent 600 deaths per year from RCS related diseases.

OSHA’s silica rule has been a source of contention between employers, labor representatives, and the Agency since its inception, due in large part to the fact that silica exposures can occur naturally as a result of ambient environmental conditions, there are severe limitations in silica testing technologies, and ambient environmental conditions cause inherent errors in any in-field testing applications. Further, OSHA’s requirement in the rule that employers adopt engineering controls to limit RCS exposures over other available technology, such as respiratory protection, has led to significant concerns over whether employers can actually comply with the new rule due to technology limitations and fiscal feasibility.

In response to the NPRM, OSHA received over 2,000 comments, totaling over 34,000 pages of material. OSHA also held public hearings, spanning 14 days, in which 200 stakeholders representing an estimated 70 organizations presented testimony. Some of the comments and testimony the Agency received in response to its proposed rule noted the following:

  • OSHA’s basis for enhancing the PEL is based on an overly conservative risk assessment that ignores studies showing that exposures to RCS above the then-existing General Industry PELA do not present a sufficient risk. OSHA has failed to demonstrate that manufacturing industries produce RCS exposures of a sufficient magnitude and frequency to warrant the new requirements imposed by the rule. Further, employers have already consistently complied with the existing limits, which have demonstrably reduced the number of silicosis cases by more than 90%.
  • OSHA’s sampling and analytical methods for RCS have a known “overall analytical error” of +/- 26 percent, which in effect requires that the method be applied to a quantity of RCS smaller than the smallest amount for which the method has been validated. OSHA further has never accounted for or addressed the problem with this analytical method. In the preamble to the final rule, OSHA discussed changes to the procedure it believes laboratories must adopt to allow them to achieve adequate sensitivity and accuracy for compliance purposes.
  • OSHA’s rule employs a surveillance based approach to the analytical assessment of residual risk associated with RCS exposures. Importantly, OSHA provides a means for employers who can show that exposures will not exceed the action level to be excluded from coverage under the standard. Unions and worker advocates will likely challenge this provision.
  • OSHA’s new rule does not address the significant costs and realities associated with its required engineering controls. Although the agencyestimated the rule would provide average net benefits of about $2.8 to $4.7 billion annually over the next 60 years and would only cost $1,242 for the average workplace covered by the rule, the agency’s estimates did not account for the significant costs associated with the rule’s increased monitoring requirements and more stringent specifications for engineering controls. As result, industry believes the cost to comply is substantially higher than estimated, particularly given that some workplaces will need customized ventilation systems to achieve compliance.
  • OSHA’s rule continues to require that employers use engineering controls over respiratory controls, ignoring the substantial improvement in the design and performance of a wide variety of respirators since the so-called hierarchy of controls was first adopted. Industry submitted evidence that such devices would be more effective for RCS exposures from cutting, grinding, crushing or drilling silica-containing materials such as concrete, masonry, tile, and rock.

OSHA’s final rule provides specific compliance dates for employers to bring operations into line with the new PEL requirements. Employers in the construction industry have until June 23, 2017 to comply with most of the requirements, but employers in the general industry and maritime sectors will have until June 23, 2018. Employers in oil and gas operations with hydraulic fracturing operations have until June 23, 2018 to comply with all provisions except Engineering Controls, which has a compliance date of June 23, 2021 for that specific industry.

As the new rule imposes a significant reduction in the PEL and requires extensive engineering and administrative controls, compliance with the new rule will likely require substantial investment from employers. In addition to employer concerns over potential compliance costs, the contention surrounding technological feasibility of the rule’s sampling requirements and exposure controls has not dissipated. Many expect there will be a judicial challenge to the rule shortly involving a number of industries and proponents of the standard.