Over the last couple of years we've seen a lot of debate on the impacts that shale gas operations can have on local and regional air quality and even on the climate. But there's been less attention paid to the potential impacts to the workers who daily toil in and around the hundreds of drilling sites. Fortunately, that's about to change.
Highlighting this very issue, the National Institute for Occupational Safety and Health (NIOSH) recently released a Hazard Alert, identifying exposure to airborne silica as a health hazard to workers conducting hydraulic fracturing operations during recent field studies.
NIOSH is working to identify other potential health risks at drilling sites, acknowledging that there is a real lack of information on occupational dust and chemical exposures in this industry.
In a 2012 presentation, “NIOSH Field Effort to Assess Chemical Exposure Risks to Oil and Gas Workers,” Eric Esswein and other colleagues with the Centers for Disease Control and Prevention, state that little is known about the magnitude of potential chemical exposures, which could include not only silica, but diesel particulates, volatile organic compounds, hydrogen sulfides, acid gases, aldehydes and various metals.
Field studies are ongoing at 11 sites in five states, including Texas. NIOSH intends to identify processes and activities where chemical exposures could occur, characterize potential exposures to vapors, gases, particulates and fumes and depending on the results, recommend safe work practices and/or propose and evaluate exposure controls.
For now, immediate attention is focused on the respirable silica, present at higher than recommended levels at some drilling sites. Silicosis, the main danger associated with breathing silica dust, is an incurable lung disease that increases the risk of lung cancer. “Short term exposure at a high enough level can result in permanent damage,” said Robert Emery, a chemical safety expert with the University of Texas Health Science Center at Houston, in July State Impact coverage.
Esswein and colleagues highlight seven primary dust generation points at drilling sites, including site traffic, sand mover top hatches and transfer belts, blender hopper sand dropping, and more.
However, silica is just one of several chemicals used during the hydraulic fracturing process that can pose hazards at well sites, according to State Impact. “There are ‘biocides’ like chlorine used to kill slime in hydraulic lines . . . fumes from the hydrochloric acid used to clean cement out of the lines . . . exhaust from diesel trucks and generators.”
It’s worthwhile to note that NIOSH predicts other likely health hazards to include diesel particulates. Environmental Protection Agency (EPA) regulates particulate matter (PM) under the National Ambient Air Quality Standards (NAAQS) and recently, the agency proposed strengthening the standards. In fact, the proposed revised standards – to be issued December 14, 2012 – would strengthen the annual “primary” fine particle standard to protect public health and would establish a separate “secondary” fine particle standard to protect visibility in urban areas. Though the PM NAAQS are established for the protection of public health across the country and not just at drilling sites, the new standard could result in additional monitors being placed in areas near high drilling activity. These monitors would provide information critical to ensuring clean air protections from the harms of PM.
August 31 ends the public comment period on these proposed standards. For the safety of shale gas drilling workers, as well as for the protection of millions of Americans impacted by health concentrations of PM, we encourage you to voice your concerns by submitting your comments to the EPA before the deadline.
Together, we can ensure cleaner Texas air as well as increased vigilance paid to the health of shale gas workers.