Accident Board Begins Two Full Investigations

Last week, the Chemical Safety & Hazard Investigation Board announced two new "root cause" investigations of recent chemical accidents. One examination will look into an accident at MFG Chemical that created a toxic cloud of allyl alcohol and hydrochloric acid and affected residents living within one-quarter mile of the Dalton, Ga., plant. The release took place during evening hours when process operators, preparing the first full-scale batch of a new chemical product, mixed allyl alcohol, cyanuric chloride, and a catalyst into a 4,000-gal vessel. Temperature and pressure rose, exceeding controls, and the vessel released a gas cloud that moved into the neighborhood, sending 184 people to the hospital while killing vegetation and fish in a nearby water body. In the second investigation, board engineers are conducting a full examination into the cause of a fire and explosion at the Giant Industries Ciniza gasoline refinery in Gallup, N.M., which injured six workers. The accident occurred in the refinery's alkylation unit, which uses hydrofluoric acid as a process catalyst and produces a highly flammable gasoline component known as alkylate. Hot alkylate was released from the process when workers removed a malfunctioning steam-powered pump from a distillation column for repair. Workers had attempted to close valves, which should have isolated the pump, but it appears that they were unsuccessful, the board noted. The chemical safety board, which is solely an investigatory body without regulatory or enforcement powers, takes about nine to 12 months to complete its investigations and issue final reports on the causes of accidents.