What is Silica Dust Monitoring?

Crystalline silica, also known as quartz, is an abundant mineral component of sand, soil, stone, concrete, mortar, brick, and other building materials.1,2

When construction, stone countertop, foundry, mining, hydraulic fracking, ceramics manufacturing, and other workers perform cutting, abrasive blasting, grinding, drilling, crushing or alter materials containing crystalline silica, these particles may be released as respirable airborne silica particles. 1

Industrial Hygiene

What are health hazards associated with Silica Dust

Without proper protection methods, silica exposure (respirable particles <5 um) can result in chronic inflammation and fibrosis in the lungs and other organs.2 Additionally, Crystalline silica has been classified as a human carcinogen and can also contribute to systemic autoimmune diseases.2

One of the diseases specifically related to exposure to respirable silica particles is silicosis. 3 Silicosis is caused by silica dust entering the lungs causing inflammation and the formation of lung nodules and scarring in the lungs (pulmonary fibrosis).3 Silicosis is a progressive disease that typically takes 10-30 years to develop after first exposure. In the early stages of the disease, a person that has silicosis will show mild symptoms such as shortness of breath, coughing, and sputum.3 As the disease progresses, symptoms such as difficulty breathing, weakness, fatigue, fever, leg swelling, night sweats, and bluish discoloration of the lips may occur. 3 Without proper treatment, severe silicosis can lead to Progressive Massive Fibrosis (PMF) and increase the risk of other health problems such as lung cancer, tuberculosis, and chronic bronchitis.3

There is no cure for silicosis, so limiting exposure and early detection are critical for saving lives and providing manageable treatment for workers exposed to silica dust.1 In 2016, the Occupation Safety and Health Administration (OSHA) released the final rule “Occupational Exposure to Respirable Crystalline Silica” in 29 CFR Parts 1910, 1915, and 1826 to update the permissible exposure limit for respirable silica and provide requirements for employers to keep workers safe.1,4

What is the Permissible Exposure Limit (PEL) for Respirable Silica Dust in OSHA’s 2016 Final Rule “Occupational Exposure to Respirable Crystalline Silica”?

In OSHA’s Final Rule for “Occupational Exposure to Respirable Crystalline Silica” (effective June 23, 2016), OSHA established a new PEL of “50 micrograms of respirable crystalline silica per cubic meter of air (50 [mu]g/m3) as an 8-hour time-weighted average” in all industries included in the rule.4

The PEL included in this new rule now aligns with the limit recommended by the National Institute for Occupational Safety and Health (NIOSH) in 1974.5

What industries are included in OSHA’s 2016 Final Rule “Occupational Exposure to Respirable Crystalline Silica” and what standards are involved?

In the Final Rule, OSHA set standards for the Construction Industry, General and Maritime Industries, as well as the Hydraulic Fracking Industry. 1 The standards contained in the final rule went into effect on June 23, 2016, and gave the Construction Industry one year to comply with most of the requirements related to silica dust, the General and Maritime Industry had two years, and the Hydraulic Fracking Industry had two years to comply with all provisions except for the engineering controls (had a compliance date of June 23, 2021).1