Inspection Detail

Inspection: 307399790 - Pacific Gas & Electric Company

Inspection Information - Office: San Francisco District Office

Investigation Summary

On May 17, 2008, a construction crew was sent to Daly City Substation to relocate three transmission conductors to a new dead-end steel structure and install a coupling capacitor voltage transformer (CCVT) on the third conductor. At the same time, a six-person Substation Crew was assigned to replace the old oil circuit breaker (CB 162; 1,200 Amp, 115 KV) with a new sulfur-hexafluoride (SF6) circuit breaker (CB 182; 2000 Amp, 115 KV). The Substation Crew was relocating the conductors from the old circuit breaker to the new one on the transformer side. The work was done on Martin/Daly City 115 KV Transmission Line #2 which had been deenergized, tested, and grounded at Martin Sub. The installation work was completed the next morning at approximately 9 a.m. Employee #1, who had been an Apprentice Lineman for almost two years, was assigned to remove the grounding devices from all three transmission lines before they were reenergized. The grounding device consisted of an 8-foot long extension pole with a 40-foot long grounding cable. Employee #1 was wearing leather gloves and working from the bucket of a boom truck. The bucket was insulated (50-56 KV DC) and had a liner but the annual test record showed that the Liner had failed when it was last tested on August 13, 2007. He removed the first two grounding devices from the outer lines and hung them on the hooks attached to the outside of the bucket. He then removed the last grounding device from the third deenergized transmission line on which the newly installed CCVT was attached. Following the removal of the third grounding device from the conductor, Employee #1 was holding the grounding cable with both hands as he tried to secure the device to the bucket. He felt an electrical shock in his hands and as he tried to break free from the contact. Employee #1 injured his left shoulder (fracture and torn tendon) and fell inside the bucket. A coworker, who was on the ground, lowered the bucket. The grounding cable, which was still connected to the steel tower, was pulled out of the clamp attached to the structure. Employee #1 was transferred to Seton Medical Center in Daly City by paramedics, where he was hospitalized overnight. He received medication for his injured shoulder while being monitored for any potential injury due to the induction contact. The incident was reported to the San Francisco District Office by the Employer on the day of the accident. The cause of the accident was a failure to maintain a safe clearance. T8 CCR 2940.2(a) requires the employees keep the safe distance specified in table 2940.2, unless the employee is properly insulated; or the energized part is properly guarded from the employee or any other conductive object. In addition, the Employer was cited for failure to take precautions to prevent any material or tool from accidently contacting the energized conductor or equipment. Other violations of Title 8 were observed and the Employer was cited accordingly.

Keywords: BOOM TRUCK, INSTALLING, SHOULDER, GLOVE, ELECTROCUTED, CIRCUIT BREAKER, ELECTRIC CONDUCTOR, ELECTRIC SHOCK, FALL, TRANSFORMER