NIOSH Finds Fracking Workers Exposed to Excessive Silica Dust

Crystalline silica, which is found in most types of rock and becomes airborne as dust, has been associated with serious diseases for many years. As early as 1974, the National Institute for Occupational Safety and Health (NIOSH) evaluated the available information on the health effects of silica, and described reports of the potentially fatal lung disease silicosis from hundreds of years ago. In 2002, NIOSH again examined the health risks of silica, and found that exposure silica causes lung cancer, in addition to silicosis and other serious and often deadly illnesses. NIOSH’s 2002 hazard review on silica can be found online here. (

Researchers at NIOSH recently published a study in which they found that workers at hydraulic fracturing sites are exposed to excessive crystalline silica, sometimes more than ten times the government’s exposure limit for silica. Crystalline silica is a component of sand used in the process of hydraulic fracturing, or “fracking.” As the authors of the NIOSH study describe, silica sand is commonly used as a “proppant,” holding open the cracks from which oil or gas is extracted.

The use of large amounts of sand in the fracking process creates crystalline silica dust. The NIOSH investigators evaluated 11 sites in five states, identifying seven points in the operations where dust was generated. Not surprisingly, workers who jobs were near sand moving operations generally experienced the highest exposures, but even employees who spent less time near those operations sometimes experienced high exposures.

The NIOSH researchers found excessive exposures at all 11 sites, in spite of the fact that many of the workers wore air-filtering respirators. Interestingly, the study noted that silica exposures were lower at one worksite in North Dakota where a ceramic substance was used as a proppant in place of some silica sand. The NIOSH study can be found online here. (​).

Among the sites studied was an operation in the Marcellus Shale Formation in Pennsylvania. The Marcellus formation runs from New York to Virginia, and runs under parts of Pennsylvania, West Virginia, Ohio, Maryland, and New Jersey as well.

While hydraulic fracturing has brought economic opportunity to our region, NIOSH’s research highlights the importance of protecting the workers whose efforts fuel that opportunity. At Hartley Law Group, we have been representing workers who have been hurt or sickened on the job for 30 years, and our clients have included workers exposed to silica, as well as the men and women of the oil and gas industry. If you or a loved one has been injured on the job, we would like to help.

Related Posts: