Beginning September 23, all U.S. construction employers must comply with the requirements of the Occupational Safety and Health Administration’s (OSHA) final rule on respirable crystalline silica. Since the 1970s, OSHA has set standards to limit workers’ exposure to silica. However, as OSHA recently stated, “the standards are outdated and do not adequately protect workers from silica-related diseases.” To help explain the dangers of silica and the impact of OSHA’s final rule, we sat down with Dan Christensen, CTEH’s director of industrial hygiene services. Check out our Q & A below:

What are the most common sources of exposure to crystalline silica dust?

Crystalline silica is a naturally occuring component of soil, sand, granite and other types of stone. In its natural form it is not hazardous. However when these materials are processed by mechanical force, small dangerous particles of silica are produced. This can occur when crushing, cutting and drilling rock or concrete; tile cutting; masonry and concrete work (i.e., road construction); mining and tunneling; demolition work; or in the manufacture of cement or asphalt pavement. Due to the sand used, oil and gas fracking is also now recognized source of silica exposure.

What are the symptoms of silicosis?

Silicosis is a progressive, debilitating and, oftentimes, fatal lung disease, which results from scar tissue replacing healthy lung tissue. Its symptoms include chest pain, shortness of breath, respiratory failure, fatigue, dry cough, loss of appetite and possible fever. Silicosis may also lead to lung cancer, bronchitis, chronic obstructive pulmonary disorder (COPD), tuberculosis, renal disease or scleroderma, a disease that affects individuals’ skin, blood vessels, joints and skeletal muscles.

How can workplaces minimize exposure to respirable crystalline silica?

OSHA estimates 2.3 million workers are exposed to respirable crystalline silica in their workplaces. To minimize workers’ exposure in abrasive blasting, employers should use all available engineering controls (i.e., blasting cabinets, local exhaust ventilation) and, where possible, substitute non-crystalline silica blasting material. Employers should not allow compressed air to be used for cleaning dusty surfaces. They should always use water sprays and wet methods for activities like cutting or drilling and require the use of approved respirators. Employees should never eat, drink or smoke near crystalline silica dust and should always wash their hands and faces before leaving impacted worksites.

How is the construction industry impacted by the final OSHA rule?

The final OSHA rule “reduces the permissible exposure limit (PEL) for respirable crystalline silica to 50 micrograms per cubic meter or air, averaged over an 8-hour shift.” Under the rule, employers must establish a written exposure control plan and designate a competent individual to implement it. The plan should identify tasks involving exposure to silica and develop methods to protect workers (i.e., engineering controls like ventilation, respirators or restricted access to high exposure areas). Employers must restrict housekeeping practices that expose workers to silica where feasible alternatives are available. In addition, they must keep records of workers’ silica exposure and offer medical exams, including chest X-rays and lung function tests, every three years for workers who are required to wear a respirator for 30 or more days a year. Finally, they must train workers on work operations producing silica and in ways to limit this exposure. (NOTE: Requirements for laboratory evaluation of exposure samples begins on June 23, 2018).