OSHA cited a fish oil plant, a metal fabricator, a staffing firm and a maintenance company for a July explosion that killed a temporary worker and critically injured another.

The temporary workers were hired to cut and weld pipes at the Omega Protein plant in Moss Point, Miss. However, the US Occupational Safety and Health Administration reported the workers were unaware and had no training to know the storage tank beneath them contained explosive methane and hydrogen sulfide gases. One worker was killed and another suffered a fractured skull, internal injuries and broken bones when the tank exploded July 28.

Accu-Fab & Construction Inc. was hired to manufacture and erect a wastewater storage, and OSHA cited it with one willful, four serious and two other-than-serious violations. The willful violation was for failure to train workers on chemical hazards among other things. Staffing provider Global Employment Services received a serious citation for the same hazard, according to OSHA.

Omega Protein received 13 citations for willful, repeated and serious safety violations, according to OSHA. The willful citation was for exposing employees to fire and explosion hazards due to Omega management's failure to inform Accu-Fab that the storage tank contained wastewater that could generate highly explosive hydrogen sulfide and methane gases. The repeated violations involve not having standard railings on open-sided floors and platforms and failing to label electrical boxes properly.

JP Williams Machine & Fabrication was doing unrelated maintenance work, but it was cited for improperly storing oxygen and acetylene cylinders, according to OSHA.

“The Omega Protein plant explosion shines a spotlight on how critical it is for employers to verify, isolate and remove fire and explosion hazards in employee work areas,” said Eugene Stewart, OSHA’s area director in Jackson, Miss. “If the employer ensured a safe environment, this tragic incident could have been prevented.”

Each company has 15 business days from receipt of its citations and proposed penalties to comply, meet with OSHA’s area director, or contest the findings before the independent Occupational Safety and Health Review Commission.