Abstract: A four-person substation maintenance crew was performing routine maintenance on transfer and disconnect switches on a 34.5-kilovolt structure in a substation. A construction crew was already on the jobsite, dismantling two sections of a 34.5-kilovolt bay just two bays south of the maintenance crew. The construction crew had already installed protective grounds on the main and transfer buses, as specified by their employer's safety manual and departmental procedures. A member of the substation maintenance crew observed these grounds and advised his supervisor. The maintenance crew decided to place their protective grounds on the incoming lines only, as the circuits were already deenergized. The incoming circuits were deenergized by air-break switches located at various locations in the field, and the switches were locked in position with the electric utility's hold cards attached. The supervisor instructed the employees to install their grounds on the incoming line and proceed with their work. (This same procedure was used for three different circuits in the substation.) At 2:45 PM, the construction crew finished their work and removed their protective grounds. The construction supervisor informed the substation maintenance supervisor, who was on the jobsite, that the construction crew's grounds had been removed. At this point, there was only one set of protective grounds installed. One of the members of the maintenance crew had just completed working on a transfer switch. He told his foreman that he was going to leave the protective grounds on and the switch closed until another crew member completed his work on a disconnect switch on the same bus. The supervisor instructed the first power line worker to open the transfer switch after he removed the grounds. One of the members of the crew apparently contacted energized parts and was electrocuted. (The original form did not indicate which employee was electrocuted or what energized part he contacted.)