Abstract: A crew of six men was assigned to remove a smelt ring from inside the walls of a rotary kiln. Employee #1 was the stand-by person who normally did air testing and was assigned to stand by the door at the opening to the kiln firebox. At the downward end of the kiln opening there was an approximately 34 in. wide by 5 ft long hole in the floor that led to the dissolver tank. An attempt was made to cover this hole with two 2 by 6 rough-cut planks and a warped approximately 4 ft 8 in. long by 4 ft wide sheet of plywood. Employee #1 was standing on or next to the floor opening cover when he fell approximately 8 ft into the dissolver tank, which contained chest-deep hot water estimated to be around 160 degrees F. The crew could hear Employee #1 calling for help, but could not immediately locate him. He was rescued after a delay of about 2 to 3 minutes. Employee #1 suffered second- and third-degree burns over 85 percent of his body.