The recent surge in hydraulic fracturing (fracking) activities in shale operations is exposing workers to dangerous levels of silica, federal officials are warning.
The Occupational Safety and Health Administration and the National Institute for Occupational Safety and Health have issued a joint hazard alert to employers in hydraulic fracturing operations, warning of the need to take steps to protect workers from silica exposure.
“Hazardous exposures to silica can and must be prevented,” said Dr. David Michaels, assistant secretary of labor for occupational safety and health. “It is important for employers and workers to understand the hazards associated with silica exposure in hydraulic fracturing operations and how to protect workers.”
The alert follows a study by NIOSH and industry partners that identified overexposure to silica as a health hazard to workers conducting hydraulic fracturing operations.
Hydraulic fracturing uses large quantities of silica sand, which is the most commonly used proppant to prevent the induced fractures in the rock from closing.
|A study of 11 fracking sites found seven primary sources of silica dust exposure during those operations. Workers downwind of sand mover and blender operations had the highest exposures.|
Because respirable silica is a hazard common to many industries and industrial processes, NIOSH began in January 2010 to collect data regarding silica exposure at hydraulic fracturing operations.
Working with oil and gas industry partners, the institute sampled the air at 11 sites in five states where hydraulic fracturing operations were taking place.
NIOSH identified seven primary sources of silica dust exposure during those operations. Workers downwind of sand mover and blender operations, especially during hot loading, had the highest exposures.
The alert states that employers must ensure that workers are properly protected from overexposure to silica.
The alert describes how a combination of engineering controls, work practices, worker training, protective equipment and, where feasible, product substitution can protect workers who are exposed to silica.
Engineering controls and work practices provide the best protection, according to OSHA. Transporting, moving and refilling silica sand into and through sand movers, along transfer belts and into blender hoppers can release dust into the air containing up to 99 percent silica that workers breathe.
Workers who breathe silica day after day are at greater risk of developing silicosis, a disease in which lung tissue reacts to trapped silica particles, causing inflammation and scarring, and reducing the lungs' ability to take in oxygen, OSHA reports.
Silica also can cause lung cancer and has been linked to other diseases, such as tuberculosis, chronic obstructive pulmonary disease, and kidney and autoimmune disease. OSHA launched a National Emphasis Program on Crystalline Silica in 2008.
‘Practical and Effective’
“The recommendations for protecting workers in the hazard alert are practical, evidence-based and effective solutions to help support the safe growth of American-made energy.” said NIOSH Director John Howard, M.D.
Kenny Jordan, executive director of the Association of Energy Service Companies, also applauded the action, saying: "We are proud of the development of an industry focus group in cooperation with those agencies which will further explore this issue, share best practices and continue to build upon the many engineering controls currently in place and those under development over the last several years.”