On January 13, 2022, workers inside the company’s fabrication shop performed a “wet test” on a newly built tank truck to check for leakage. This entailed running diesel test fuel through different tank compartments and other truck components. This was a routine operation at the workplace. Workers knew never to use gasoline, and the company had a standard operating procedure that prohibited gasoline or any tanker truck containing gasoline from entering the fabrication shop. The diesel test fuel was stored in a tank outdoors.
The day before, another worker had used diesel test fuel to “wet test” a newly built tank truck OUTDOORS. They left the diesel test fuel in the truck to calibrate the diesel meter. At some point, more fuel was added to the truck. On January 13, a worker pumped the diesel test fuel from the truck OUTSIDE into the truck inside the fabrication shop. That afternoon, flammable liquid vapors in the vicinity of the truck inside the shop ignited, causing one explosion followed by a second larger explosion. Seven (7) workers were injured, six fatally and one critically as a result.
Following the explosions and fire, several fuel storage tanks at the workplace were tested for contamination. Gasoline was identified as a contaminant in several diesel tanks, and diesel was identified as a contaminant in a gasoline tank.
An Ontario Fire Marshall investigation found that the gasoline involved in the explosion resulted from the use of CONTAMINATED diesel test fuel in the “wet test.”