Evaluation of some potential chemical exposure risks during flowback operations in unconventional oil and gas extraction: preliminary results
Approximately 562,000 workers were employed in the U.S. oil and gas extraction industry in 2012; nearly half of those workers were employed by well servicing companies, which include companies that conduct hydraulic fracturing and flowback operations. To understand possible risks for chemical exposures in modern oil and gas extraction operations, the National Institute for Occupational Safety and Health (NIOSH) initiated the Field Effort to Assess Chemical Exposures in Oil and Gas Workers. Initial research identified exposure risks for respirable crystalline silica during hydraulic fracturing as an occupational health hazard. This report describes industrial hygiene sampling during flowback operations at six unconventional oil and gas extraction sites in Colorado and Wyoming during spring and summer 2013. The results are considered preliminary; additional exposure assessments are needed to better understand the range of possible exposures, risk factors, and controls during flowback operations.