What You Need to Know: OSHA’s Proposed Amendments to Respirable Silica Standards

By Evan Gurley

Winds of change have been blowing in from the U.S. Occupational Safety and Health Administration (OSHA) recently, and one of the more significant changes affecting the precast industry is a proposal to tighten existing standards for exposure to respirable crystalline silica.

OSHA has asked for a public comment period addressing proposed amendments to its current standards for occupational exposure to respirable crystalline silica. This is a proposal and not a final rule, so OSHA encourages the public to participate in development of the rule by submitting comments and participating in public hearings. But you’d better hurry: Comments are due Jan. 27, 2014, and the public hearing will start March 18, 2014. Details on how to participate can be found at the end of this article.

What is OSHA’s thinking?

It helps to start with a definition of the subject. OSHA describes respirable crystalline silica as particles at least 100 times smaller than ordinary sand you may encounter on beaches and playgrounds. It is created during work operations involving stone, rock, concrete, brick, block, mortar and industrial sand. Exposures to respirable crystalline silica can occur when cutting, sawing, grinding, drilling and crushing these materials. These exposures are common in brick, concrete, pottery manufacturing and operations using industrial sand products.

The proposal was issued by the Assistant Secretary of Labor for Occupational Safety and Health, who wanted to determine whether employees who are exposed at the current permissible exposure limits (PELs) face a significant risk to their health and whether the proposed tougher standards will substantially reduce that risk.

OSHA currently enforces PELs for respirable crystalline silica in three sectors: general industry, construction and shipyards. These PELs were adopted in 1971 shortly after the agency was created and have not been updated since. The PEL for quartz (the most common form of crystalline silica) in general industry is 100 micrograms per cubic meter (µg/m³) of air as an eight-hour, time-weighted average. The current PEL for construction is 250 µg/m³ and 50 µg/m³ for the two other forms of crystalline silica (cristobalite and tridymite).

OSHA is proposing a new PEL for respirable crystalline silica (quartz, cristobalite and tridymite) of 50µg/m³ in all industry sectors covered by the rule. OSHA is also proposing other elements of a comprehensive health standard, including requirements for exposure assessment, preferred methods for controlling exposure, respiratory protection, medical surveillance, hazard communication and recordkeeping.

The new standard would also set an action level of 25 µg/m³, meaning that employers would be required to conduct periodic exposure monitoring for employees. The rule also includes:

• Provisions for measuring how much silica exposure workers face
• Limits on workers’ access to areas where exposures are high
• Medical exams for workers with high silica exposures
• Training for workers about silica-related hazards and how to limit exposure

The standard would make controlling silica dust the primary method for reducing employee exposure. Rules about personal protective equipment (PPE) are included, but PPE would be a last resort to reduce exposure after first taking measures to control dust, such as:

• Wetting work areas to keep the dust from getting into the air
• Enclosing a work area (process isolation)
• Using a vacuum to collect dust at the point it’s created before workers can inhale it

OSHA estimates the rule will cost the average facility $1,242 per year, and the cost for small facilities with fewer than 20 employees would be about $550. Other industry estimates have been much higher.

What do others think?

The Crystalline Silica Panel of the American Chemistry Council (ACC) argues that the current PELs are sufficient. “The best available science, to our understanding, shows that the current OSHA PEL for quartz of 0.1 mg/m3 is appropriate to protect against silica-related disease, provided it is adhered to strictly,” said the ACC in a recent news release. “Accordingly, achieving full compliance with, and enforcement of, the current PEL is the best way to protect silica-exposed workers.”

The ACC added that the data from the U.S. Centers for Disease Control (CDC) show a greater than 90% reduction in the silicosis mortality rate from 1968 to 2010, demonstrating the effectiveness of the current PEL since its adoption in 1971 as well as improvements in industrial hygiene practices. “While cases of silicosis still exist, the panel believes that the current PEL is both appropriate to protect workers and is an enforceable limit, and that the cases of silicosis that still occur result from noncompliance with the current PEL,” it said. “Accordingly, the panel does not believe there is a need for a new crystalline silica standard with a reduced PEL.”

The National Association of Manufacturers (NAM) has pointed out that compliance with the new proposed levels would lay more responsibility on employers in several areas:

• Medical surveillance – Must be available to each employee exposed above the PEL for at least 30 days at no cost to the employee with periodic exams, including physicals, chest X-rays, pulmonary tests, latent TB tests and any other test deemed appropriate by the health care provider.
• Communication – Must include inventory, labels, perpetual training, etc., for hazards including cancer, lung effects, immune system effects and kidney effects in the hazard communication program. The employer must also ensure that the employee can demonstrate knowledge of these elements.
• Recordkeeping – Must keep records of air monitoring test procedures and results and identify the lab performing the analysis and its process, the identity of all employees monitored, the data and medical monitoring.
• Compliance schedule – Must comply within 180 days for everything except engineering controls and lab requirements, which are within one and two years, respectively.

The ACC said that while compliance with the current PEL is required and necessary to continue the reduction in silicosis, reducing the PEL is not. “OSHA compliance sampling over several recent decades show a noncompliance rate with the current … PEL in excess of 30%,” it said. “Moreover, attempting to comply with the sharply reduced PEL presents enormous feasibility challenges for the many job-producing sectors where silica exposures may occur. Furthermore, it is unclear how the proposed PEL could be enforced given that serious questions remain about the ability of laboratories to measure silica exposures accurately and reliably at such low concentrations.”

The National Precast Concrete Association opposes the OSHA proposed rule and has submitted public comments in support of retaining the current PEL of 100. NPCA supports adherence to existing standards and more OSHA education about best practices for controlling exposure and encouraging respirator usage. In addition, NPCA and a coalition of concrete-related trade associations have joined the American Chemistry Council’s Crystalline Silica Panel in support of the ACC’s scientific argument that the current PEL is sufficient.

What do you think?

To make their voices heard, precasters and those in other industries are encouraged to submit their comments. Written comments are due Jan. 27, 2014. The deadline for submitting a notice of intent to testify at the hearing was Dec. 12, 2013; the public hearing will be held March 18, 2014, in the auditorium of the U.S. Department of Labor, 200 Constitution Avenue NW, Washington, D.C.

All submissions must include the agency name and the docket number for this rulemaking (Docket No. OSHA-2010-0034). All comments, including any personal information you provide, are placed in the public docket without change and may be made available online at regulations.gov. Therefore, OSHA cautions you about submitting personal information such as social security numbers and birthdates.

• Electronically: You may submit comments and attachments electronically at regulations.gov.
• Fax: If your submissions, including attachments, are not longer than 10 pages, you may fax them to the OSHA Docket Office at (202) 693-1648.
• Mail, hand delivery, express mail, messenger or courier service: You must submit your comments to the OSHA Docket Office, Docket No. OSHA-2010-0034, U.S. Department of Labor, Room N-2625, 200 Constitution Avenue NW. Washington, DC 20210.

Evan Gurley is a technical services engineer with NPCA.