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OSHA oversight needed for unique onshore drilling hazards: CSB

Posted On: Jun. 12, 2019 1:16 PM CST


The U.S. Occupational Safety and Health Administration should develop effective oversight that addresses the unique hazards of the onshore drilling industry in the wake of a blowout that fatally injured five workers at the Pryor Trust gas well in Oklahoma last year, according to a report released by the U.S. Chemical Safety and Hazard Investigation Board.

The Jan. 22, 2018, blowout and rig fire at the gas well located in Pittsburg County, Oklahoma,  was caused by the failure of two preventive barriers intended to stop a blowout, according to the CSB report issued on Wednesday. The Pryor fire was the deadliest U.S. drilling incident since the 2010 Deepwater Horizon rig explosion that killed 11 workers and was also investigated by the CSB.

Industry best practices recommend always having two protective barriers in place during drilling operations, but the primary barrier – hydrostatic pressure in the well, produced by drilling mud – and the secondary barrier – human detection of gas flowing into or expanding in the well and activation of the rig’s blowout preventer both failed, according to the CSB’s investigation. Several factors contributed to the loss of barriers, including a lack of planning, training, equipment, skills and procedures, according to the final report.

“Our investigation found significant lapses in good safety practices at this site,” CSB Interim Executive Kristen Kulinowski said in a statement on Wednesday. “For over 14 hours, there was a dangerous condition building at this well. The lack of effective safety management at this well resulted in a needless catastrophe.”  

The final incident report also identified a lack of regulations governing onshore drilling safety and shortcomings in safety management systems and industry standards utilized by the industry and urged stakeholders to address these issues. 

There are no regulations specifically developed for onshore oil and gas well drilling, according to CSB’s investigation. In 1982, OSHA proposed a standard for the oil and gas well drilling and servicing industry, but no final action was taken. In 1999, OSHA announced it intended to propose such a standard, but withdrew it from the regulatory agenda due to resource constraints and other priorities, according to the report.

Because oil and gas well drilling is exempted from the OSHA’s process safety management standard, which governs safety for chemical processing facilities, OSHA has been utilizing the Occupational Safety and Health Act’s general duty clause for enforcement against these operations. But this fails to address the unique safety hazards associated with drilling for oil and gas, the CSB concluded.

The number of fatalities in the private oil and gas extraction industries has fluctuated, hitting a 10-year high of 144 in 2014 before trending back downward, with 81 deaths reported in 2017, according to data from the U.S. Bureau of Labor Statistics.

Sounding the alarm

The CSB also found that the drilling contractor failed to maintain an effective alarm system, with the entire alarm system disabled by rig personnel likely because of excessive “nuisance” or unnecessary alarms, which contributed to workers being unaware that flammable gas was entering the well during operations before the incident, according to the report.

“An effective alarm system is a method to help workers become aware of hazardous conditions like gas entering the well,” Investigator Lauren Grim said in the statement. “With the alarm system off, the safety of the operation solely relied on workers to either visually identify signs of the gas influx or calculate volume differences that could indicate gas influx — and in this case neither method was effective and workers were unaware of the very large gas influx into the well before the incident. As a result, the workers had little knowledge of the impending disaster.” 

At the time of the blowout, three workers were in the driller’s cabin while two other workers who were on the rig floor ran into the driller’s cabin during the blowout and fire. All five of these workers were killed. 

“When the blowout mud and gas ignited, it created a massive fire on the rig floor,” Ms. Grim said. “All five of the workers inside the driller’s cabin were effectively trapped because fire blocked the driller’s cabin’s two exit doors. Our investigation found that there is no guidance to ensure that an emergency evacuation option is present onboard these rigs or can protect workers in the driller’s cabin from fire hazards.” 

The CSB also called on the American Petroleum Institute to address design improvements needed to protect driller’s cabin occupants from blowout and fire hazards and to create guidance on alarm management for the drilling industry to help ensure alarm systems are effective in alerting drilling crews to unsafe conditions.

“As onshore oil and gas extraction grows, it is imperative that the industry is using proven and reliable safety standards and practices,” Ms. Kulinowski said. “If some of these safety practices had been in place, this tragedy could have been averted. Our report lays out a strong case for recognizing the hazards in this industry and ensuring the safety of its workers.”

Spokespersons for lease holder Oklahoma City-based Red Mountain Energy LLC, well operator Red Mountain Operating LLC and Houston-based drilling contractor Patterson-UTI Drilling Co. LLC could not be immediately reached for comment.

“Our thoughts are with the loved ones of the workers who lost their lives in this incident,” Erik Milito, API’s vice president of upstream and industry operations, said in a statement on Wednesday. “The oil and natural gas industry works closely with OSHA and other regulatory agencies to enhance safety and reduce risks with the goal of zero incidents. When it comes to safety, API has developed dozens of standards under the American National Standards Institute’s accredited process that further safety in operations. We will review the report and consider its recommendations.”