Abstract: At approximately 2:30 p.m. on March 7, 1991, Employee #1 was attempting to stop a leak in a pipe fitting when the flange opened, releasing a 4 in. blind flange. The 3 lb metal flange, propelled by water pressure of 80 to 90 psi, struck Employee #1 on the left side of the face. He sustained eye and facial injuries that required hospitalization. Subsequent investigation showed that the coupling, gasket, and blind flange were appropriate for the job, but that the method of preparation was unsafe. The fitting should have been metal to metal, without a gap, and the line should not have been opened under pressure. These hazardous conditions should not have existed, and would have been recognized by Employee #1 had he been properly trained.