Page 167 Case Study #2
Question: (Unexpected Gas) A man was killed by an explosion when another worker attempted to
cut through the top of one of two old steel drums using a handheld grinder. Both barrels had
contained a fruit concentrate but were never cleaned. The sparks generated by the grinder ignited
hydrogen gas that had been generated from the contents' residue after standing for many years.
Because there was a defective sterile coating separating the walls of the drum from the concentrate,
the acid in the fruit concentrate reacted with the metal of the drum and formed hydrogen gas. The gas
accumulated, and the pressure caused the drum ends to bulge. This deformation made it impossible
to open the drum with the drum opener, and a hole was punched into the top of each drum. One
worker was attempting to add water to one drum in order to displace the remaining gas, while
another worker attempted to open the other drum with a grinder. Sparks ignited the hydrogen gas,
causing an explosion and a fire. The fire was extinguished, but one worker lost his life. The defective
drums had been recalled years before by the supplier, and only three remained unaccounted
for before the accident. What steps would you take to ensure that this event was never repeated?