OSHA Hazard Information Bulletins
Underground Storage Tanks (USTs)

August 31, 1990






  • Hazard Information Bulletin on Underground Storage Tanks (USTs)

The Directorate of Technical Support issues Hazard Information Bulletins (HIBs) in accordance with OSHA Instruction CPL 2.65 to provide relevant information regarding unrecognized or misunderstood safety and health hazards, inadequacies of materials, devices, techniques, and engineering controls. HIBs are initiated based on information provided by the field staff, studies, reports and concerns expressed by safety and health professionals, employers, and the public. Information is compiled based on a comprehensive evaluation of available facts, literature and in coordination with appropriate parties. HIBs do not necessarily reflect OSHA policy.

Several million underground storage tank systems (USTs) in the United States contain petroleum or hazardous chemicals. Tens of thousands of these USTs, including their piping are currently leaking. Many more are expected to leak in the future. Leaking USTs can cause fires or explosions that threaten worker's safety.

In December 1988, the Environmental Protection Agency (EPA) implemented underground storage tank regulations requiring UST owners to upgrade or remove from service tanks that do not meet EPA standards. Since the implementation of EPA's tank regulations, many occupational injuries and fatalities have occurred; a result of cave-ins, explosions, and chemical overexposure. Clearly, this indicates that UST owners and service providers may be unaware of the dangers associated with improper tank servicing, closure, or removal. UST closure, removal and servicing involve exposures to numerous hazards which are listed below:

  • trenching and excavation
  • tank pressure testing
  • purging and inerting of tanks
  • buried utilities
  • heavy equipment operation
  • fire and explosion hazards
  • chemical exposure to hazardous substances
  • tank/confined space entry
  • general safety hazards, including ignition sources, electrical hazards, powered equipment hazards, walking working surface hazards

Since tank servicing and closure operations involve explosive vapors and/or hazardous chemicals, potential ignition sources, open pits and other perils, compliance officers have a need to be able to recognize the potential dangers of tank servicing and closure operations. The attached copy of the video/booklet set, Tank Closure Without Tears: An Inspector's Safety Guide, prepared by New England Institute Water Pollution Control Commission, will serve as a suitable training aid. This material will help compliance officers to recognize and evaluate potential hazards and learn how such hazards can be controlled. A listing of other references related to safety during tank closure appear on the last page of the booklet.

Please distribute this bulletin to all area offices, State Plan States and Consultation Project Officers.