Abstract: On January 12, 1994, Employee #1 was preparing a batch of Pegosperse 50MS (emulsifier) in vessel C-2. Upon completion of product, the quality control lab reported that the pH was too high and the Pegosperse 50MS needed to be bleached. Employee #1 started the bleaching process by adding sodium chlorite 31 percent solution to the mixture, starting a nitrogen sparge, and waiting for 1 1/2 hours before adding sodium borohydride. Employee #1 had reached the step of adding the sodium borohydride when he decided to relieve the pressure in the vessel by opening the valve used to introduce sodium chlorite. As he opened the valve, sodium chlorite (liquid) residue discharged, spraying the grating and the plastic bucket which contained sodium borohydride. The sodium borohydride reacted with the sodium chlorite, producing hydrogen gas which flashed into Employee #1's face. He was wearing splash goggles as face and eye protection. The flash caught him in the face, and his entire face sustained second-degree burns. Fellow operators called the Long Beach Fire Department who brought Employee #1 to Long Beach Memorial Medical Center where he was admitted.