Inspection Detail

Inspection: 119690261 - El Camino Hospital

Inspection Information - Office: Fremont District Office

Investigation Summary

An employee had a work order to repair a leaking pipe on a water softener in a boiler room. The work required welding and cutting with an electric welder. The employee brought a Miller Arc welder with him to the boiler room. The boiler room did not provide a suitable electric outlet for the welder, so the employee obtained a 480-volt, three-phase pigtail extension cord adapter. The adapter had three alligator clips at one end. The employee connected the alligator clips to a 15-ampere circuit breaker in a motor panelboard and connected the cord connector on the adapter to the attachment plug on the welder's power supply cord. When he energized the welder, the circuit breaker tripped. Following written instructions, the employee notified the chief engineer, who determined that the welder's internal wiring was set at 240 volts. The chief engineer and the employee adjusted the wiring so that the welder could run on 480 volts. The employee operated the welder with no problems for the rest of the day, and he used the welder for approximately 1 hour over that period. At the end of the day, he turned off the welder and the circuit breaker and stored the welder in the boiler room overnight. The next day, the employee, who was accompanied by a coworker, returned to the boiler room to finish his work. A fixed metal ladder to an overhead work area was near the welder. The employee connected the welder and turned on the circuit breaker. The two employees were discussing the proper way to proceed with the work. The coworker was leaning on the welder, and the employee was on the other end. The employee placed his right foot on the bottom rung on the ladder and his right hand on the ladder and then touched the handle on the welder. He received an electric shock and could not let go of the welder. He was finally able to break himself from the ladder rung and fell to the concrete floor. He was hospitalized with a fractured hip. The equipment grounding conductor on the welder's attachment plug had been attached to an ungrounded circuit conductor.

Keywords: E GI V, ELECTRICAL, WELDER, ATTACHMENT PLUG, GROUND FAULT, EQUIPMENT GROUNDING, ELECTRIC SHOCK, FALL, UNTRAINED, EQUIPMENT APPROVAL