Chemical Safety Board calls on OSHA to provide guidance on process hazard analysis

Washington — OSHA should develop guidance on the process hazard analysis element of its standard on process safety management of highly hazardous chemicals (1910.119), the Chemical Safety Board recommends in a final report on an April 2018 explosion and fire at a Wisconsin refinery.

CSB makes 16 recommendations in the report that are directed at OSHA, the Environmental Protection Agency, the American Petroleum Institute, two energy companies and the Husky Energy refinery in Superior.

The explosion occurred in the refinery’s fluid catalytic cracking unit while workers were on a break during a scheduled maintenance shutdown. Debris from the ensuing blast flew about 200 feet and punctured an aboveground storage tank containing asphalt. This caused more than 15,000 barrels of hot asphalt to spill into the refinery. The asphalt ignited about two hours later, resulting in a large fire.

OSHA’s PSM standard requires employers to have safety programs that identify, evaluate and control hazardous chemicals. CSB calls for the recommended agency guidance to place particular focus on safe operating procedures during transient operations – including startup, shutdown, standby and emergency – in facilities with processes covered by the PSM standard.

“Transient operations can pose unique hazards that may not occur during normal process operations,” the report states.

In addition to the recommendations, CSB outlines multiple lessons aimed at preventing incidents and “driving chemical safety change” within the industry. They include:

• Ensure operators understand how air or oxygen may enter during transient operations involving flammable materials, and how oxygen should be purged from the system to prevent the formation of flammable mixtures.

• Understand the process and reasoning behind venting and purging procedures and the impact these carry on process units.

• Perform process hazard analyses on critical operating procedures to spotlight hazards that occur during transient operations.

• Include in operator training hands-on opportunities for “rare but critical tasks,” including shutting down a process unit safely for a turnaround.

“These safety issues seek to address incident causes,” CSB member Sylvia Johnson said in a press release. “We call on refineries, trade groups, and regulators to examine our final report and apply the key lessons to help ensure safe operations at facilities throughout the country and to develop and adopt effective emergency response practices.”