Abstract: At approximately 11:30 p.m. on January 16, 1989, Employee #1 entered a 6,500 gallon tanker trailer to finish cleaning the inside. He was carrying a 5 gallon bucket that was one-quarter full of a cleaning agent, Niagara Trex 1900 presol. After approximately five to seven minutes, the employee was overcome by vapors from the solvent and passed out at the bottom of the tank. A coworker positioned outside the tank trailer was washing another tank trailer and checking on Employee #1 every three to five minutes. When he next checked, he saw Employee #1 lying on the bottom at the tank trailer and immediately asked someone to call 911. The coworker then entered the tank trailer without wearing the appropriate respiratory apparatus and without establishing constant communication with another employee outside of it. The coworker could not remove Employee #1 before he was overcome by the solvent's vapors and had to exit the tank. Emergency help arrived and Employee #1 was transported to a hospital, where he was pronounced dead. Employee #1 had not been wearing a safety harness, lifeline, or respirator, and a supply of fresh air was not provided. He also was not in constant communication with the coworker who was monitoring him.