Abstract: Two employees were at an oil field tank battery location trying to provide electric power to another location so that they could pump salt water from a gas well. The two employees were checking, installing, and switching fuses in a 480-volt main circuit box and in a smaller 480-volt box housing a 240-volt control. One of the employees installed three cartridge fuses into the main box and started the salt-water pump to test for electric power. He then told his coworker that they would transfer the good fuses to the smaller box. The first employee opened a switch to deenergize the smaller box. He did not, however, deenergize the main box. As he was pulling fuses from the main box, he contacted energized parts and was electrocuted. His coworker received an electric shock when he attempted a rescue. (The coworker's injury was not listed on an injury line in the original report.)