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U.S. Court of Appeals Upholds OSHA’s New Rule Limiting Exposure to Silica

As we near the 2018 peak season for many construction projects, it is important for contractors to ensure adherence to OSHA’s new silica rules which were upheld by the U.S. Court of Appeals for the District of Columbia Circuit Court on December 22, 2017. OSHA began enforcing the new rules for standard construction as of September 23, 2017. For general industry and maritime, the rules will begin enforcement on June 23, 2018.

Crystalline silica is a common mineral found in many naturally occurring materials such as soil, sand and granite. It is frequently used in common building products like mortar, concrete, sand, bricks, blocks, rocks and stones. Exposure to breathable silica dust has been stated to cause silicosis, lung cancer, other respiratory diseases and kidney disease.

Exposure to silica can occur during construction-related tasks when using masonry saws, grinders, drills or jackhammers, performing milling, and using heavy equipment for grading and excavating with silica-containing materials.

On March 25, 2017, OSHA issued their “final rule” on occupational exposure to respirable crystalline silica. The rule applies to all occupational exposures to respirable crystalline silica in construction work. Prior to this new standard, OSHA allowed 250 micrograms of respirable crystalline silica per cubic meter of air over an 8-hour time weighted average (TWA). The current standard drastically reduces that permissible exposure limit (PEL) to only 50 micrograms of respirable crystalline silica per cubic meter of air over the 8-hour TWA.

The construction industry, while sharing OSHA’s concern over the safety and wellbeing of its workers, challenged OSHA’s new exposure standard arguing, among other things, that compliance is not technologically and economically feasible. On December 22, 2017, the U.S. Court of Appeals for the District of Columbia Circuit Court issued a decision upholding OSHA’s new standard for occupational exposure to crystalline silica. The Court’s decision means that the new rule on silica exposure remains in effect as written.

As a result, employers must continue to use engineering controls and work practices as the primary means of maintaining exposure to silica dust at or below the PEL. This is typically achieved through one or more of the methods contained on Table 1 of the new standard, which is entitled “Specified Exposure Control Methods When Working with Materials Containing Crystalline Silica.” Table 1 identifies eighteen (18) common construction tasks that generate high exposures to respirable crystalline silica and for each task, specifies engineering controls, work practices and respiratory protection required.

The focus of this rule change is to protect workers from silica dust exposure by implementing engineering controls such as wet systems or vacuum systems to control the dust exposure. The new rule also prohibits dry sweeping, dry brushing and the use of compressed air as methods to clean worksites if doing so could contribute to employee exposure to silica unless wet cleaning methods are not feasible.

Use of respirators remains a permissible means to satisfy the requirements, with the type of respirator dependent on the task and type of tool being used. There are also distinctions made in terms of how long an employee is using the equipment creating dust during a shift that dictates what level of protection is required.

A copy of Table 1 that breaks down the protection requirements based on type of work being conducted and the duration of the exposure is available at:

Employers who fully and properly implement the engineering controls, work practices and respiratory protection specified for a task on Table 1 are not required to measure respirable crystalline silica exposures to verify that levels are at or below the PEL for the workers engaged in the Table 1 task. Also, the new 50 micrograms of per cubic meter standard does not apply where exposures will remain low under any foreseeable conditions such as mixing mortar, pouring concrete footings, slab foundation and foundation walls, removing concrete framework or finishing drywall.

When Table 1 identifies that respiratory protection is necessary for a particular construction task that creates exposure to silica dust, the level of protection will be categorized under an Assigned Protective Factor (APF), either APF 10 or APF 25. An APF 10 respiratory device would be a fitted N95 dust mask or a half-face cartridge respirator. An APF 25 device would be a Powered Air-Purifying Respirator (PAPR).

For employers within the construction industry, this means that you remain required under OSHA’s new rule on silica dust exposure to:

  • Implement a written exposure control plan that identifies tasks that involve exposure and methods for how to protect your employees;
  • Designate a competent person to implement the written exposure control plan;
  • Restrict housekeeping practices that expose workers to silica where feasible alternatives are available;
  • Offer medical exams—including chest x-rays and lung function tests—every three years for workers who are required by the standard to wear a respirator for 30 or more days per year;
  • Train workers on the scopes of work that result in silica exposure and ways to limit that exposure; and,
  • Keep records of your employees’ silica exposure and medical exams.

Also, do not overlook the importance of employee training on this issue. This is a “performance-based” standard so compliance is based on your employees’ ability to perform or demonstrate knowledge of the new rules. OSHA expects that 1 full hour, on average, will be required for covering most workers to properly educate them on compliance with this new rule.

If you have questions on this new rule, please contact your Davis & Kuelthau attorney, the author noted above or our Construction Industry practice chair linked here.