OSHA has cited RKM Utility Services Inc. for failing to protect workers from hydrogen sulfide after an employee died after exposure to dangerous levels of the gas while working in a trench in Dallas, Texas.

OSHA inspectors determined that the company exposed employees to a hazardous atmosphere, failed to train employees on the health hazards of hydrogen sulfide, and did not drain water from the trench. The company faces penalties of $422,006.

Hydrogen sulfide is flammable and toxic, particularly in confined spaces such as trenches and sewers. Employers are required to test the air to detect the presence of the gas, use exhaust systems to reduce hydrogen sulfide levels, train workers on hazards and control methods, and provide personal protective equipment if control methods used are not sufficient to reduce hydrogen sulfide levels.