What is Crystalline Silica?
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, bricks, blocks, rocks and stones. Exposure to breathable silica dust can cause silicosis, lung cancer, other respiratory diseases and kidney disease.
Who is at risk from exposure to crystalline silica?
Worker exposure to silica can occur during construction tasks impacting silica-containing materials such as using masonry saws, grinders, drills, jackhammers, performing milling and using heavy equipment for grading and excavating.
What is OSHA's new crystalline silica rule?
In March 2016, the Occupational Safety and Health Administration (OSHA) issued the Final Rule on Occupational Exposure to Respirable Crystalline Silica for construction. The new rule reduces the permissible exposure limit (PEL) for crystalline silica from 250 to 50 micrograms per cubic meter of air (μg/m3), averaged over an eight-hour shift. The new rule also requires the use of engineering controls, such as ventilation and wet methods for cutting and sawing crystalline silica-containing materials, to reduce workers’ exposure to silica dust.
What is required in the silica rule to keep silica exposures at or below the PEL?
Employers must use engineering controls and work practices as the primary way keep exposures at or below the PEL. Employers must either use a control method in Table 1 - "Specified Exposure Control Methods When Working with Materials Containing Crystalline Silica" or they can measure workers’ exposure to silica and independently decide which dust controls to limit exposures to the PEL.
The standard does not apply where exposures will remain low under any foreseeable conditions, e.g., when only performing tasks such as mixing mortar; pouring concrete footers, slab foundation and foundation walls; removing concrete formwork; or finishing drywall.
What is Table 1?
Table 1 is a compliance option that is intended to protect workers from silica exposures. It identifies 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. 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 workers engaged in the Table 1 task.
What are the other requirements of OSHA’s a new crystalline silica rule?
After choosing a silica control method, employers are required to:
- Implement a written exposure control plan that identifies tasks that involve exposure and methods for how to protect workers (NAHB Sample Written Silica Control Plan).
- 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 work operations that result in silica exposure and ways to limit exposure
- Keep records of workers’ silica exposure and medical exams
When must employers comply with the standard for construction?
Construction employers must comply with all requirements of the standard by September 23, 2017, except requirements for laboratory evaluation of exposure samples, which begin on June 23, 2018.
Numerous State Plans have completed adoption of the silica standard. (See the status of your state.) If you are operating in an approved OSHA State Plan, builders will need to check with their local administrator for further information on the silica standard in their state.