Abstract: At approximately 8:45 a.m. on July 9, 1997, Employee #1 added powdered chlorine chemicals to the chlorinator at a hotel swimming pool. The chemicals reacted quickly with the water and the chemicals already in the chlorinator, causing pressure to build up and the chlorinator to explode. The lid blew off and struck Employee #1 in the head. He suffered a laceration that required 21 stitches to close. Normally, chlorine tablets, not chlorine powder, were used in this chlorinator. Employee #1 had not received training or hazard communication information related to pool chemicals. The employer was cited for deficiencies in its hazard communication program.