Abstract: At approximately 12:55 p.m. on May 13, 1986, Employees #1, #2, and #3 of B. F. Goodrich and Employees #4 and #5 of Ogdor Allied Services Corporation, an on-site contractor, were in the vicinity when .a polyvinyl chloride reactor, which had been changed and set up to start the reaction, released a massive amount of vinyl chloride through a manway. The manway came loose and struck the overhead piping and structural beams, resulting in an explosion and fire that injured Employees #1 through #5. Employees #1, #2, and #3 were sent to the hospital: Employee #1 was admitted and treated for burns; Employee #2 was treated for burns and heat exhaustion; and Employee #3 was treated for burns. Employees #4 and #5 were treated for bruises and sprains.