A contractor was hired to HP clean a vessel. The vessel is connected to another vessel with a different equipment number. The superviser saw that the second vessel needed cleaning, so he sent a man in to clean it. Unbeknown to him the second vessel contained a catalyst sludge that traps gas and fumes.
The cleaner operator disturbed the sludge surface thereby releasing the entrapped gas and fumes. He was subsequently overcome by the fumes, and had to be rescued under very difficult circumstances from the thick sludge. The production stand-by failed to prevent the contractor from entering the second vessel, and he was subsequently disciplined.
Lessons learned: Work on the Right Equipment
by Marius Grobler