A 29-year old male welder was assigned to work on an outdoor concrete platform
attached to the main factory building. He wheeled a portable arc welder onto the
platform. Since there was not an electrical outlet nearby, he used an extension cord to
plug in the welder. The male end of the cord had four prongs and the female end was
spring-loaded. The worker plugged the male end of the cord into the outlet. At that
instant, the metal case around the power cord plug became energized, electrocuting
the worker.
An investigation showed that the female end of the extension cord was broken. The
spring, cover plate, and part of the casing were missing from the face of the female
connector. Also, the grounding prong on the welder power cord plug was so severely
bent that it slipped outside the connection. Therefore, the arc welder was not grounded.
Normally, it would have been impossible to insert the plug incorrectly.
Enlist safety practices before, during and after work to prevent this from happening to
you or one of your co-workers.