On May 19th, 2014, NIOSH posted a Science blog titled “Reports of Worker Fatalities during Flowback Operations.” This blog post provided information that NIOSH received from several sources indicating that acute exposures to hydrocarbon gas and vapors likely played a role in the deaths of at least four workers in the oil and gas extraction industry.

In an OSHA hazard alert, “Hydraulic Fracturing and Flowback Hazards Other than Respirable Silica,” (issued in late 2014), the agency states that more workers are potentially exposed to the hazards created by hydraulic fracturing and flowback operations due to the large increase in the number of these operations in the past decade.