On February 2, 2011, Employees #1 and #2 worked for a petroleum and petroleum product company. Employee #1 was on top of a transport tanker into which the firm’s vice-president transferred #1 diesel fuel, mixing it with about 1,000 gallons of #2 diesel fuel. Employee #2 was on the ground.
After “splash filling” the center tank with about 300 gallons of #1 diesel fuel, the firm’s vice president attempted to transfer the remainder of the #1 diesel to the truck’s front tank. He was going to do this task through “switch loading.” The front tank had previously contained 3,500 gallons of unleaded gasoline. Now, it contained only vapors.
An explosion occurred, and the resulting fire consumed 1,000 gallons of gasoline and 1,300 gallons of diesel fuel in the tanker trailer. The older diesel tank truck was severely damaged but still contained about 1,000 gallons of #1 diesel. Employee #1 was killed in the fire on top of the tanker. The fire spread to Employee #2, who was on the ground. His clothing caught on fire, but he escaped with only minor burns.
Several causes were believed to have led to the generation, accumulation, and discharge of static electricity in the presence of flammable gasoline vapors, gasoline liquid, and diesel liquid. They included, but were not limited to these: