A transformer explosion yesterday at O'ahu Community Correctional Center has raised concerns as to whether untrained inmates should be performing work-line tasks that could be hazardous.

Edwin Shimoda, institutions division administrator of the Department of Public Safety's community correctional centers, said two inmates on a supervised work line suffered injuries from an electrical shock set off when one of them accidentally stepped on the cover of a transformer, causing it to explode.

The 53-year-old inmate who triggered the explosion suffered a wrist injury in a fall from about seven feet. He also had burns on his leg.

Another inmate, 41, holding a metal ladder for the inmate who fell, sustained burns to his hands.

Both were taken to The Queen's Medical Center after the 11:30 a.m. accident and were still being treated for injuries at 6 p.m. but not admitted, said Shimoda.

According to Shimoda, the work line was assigned to remove a protective fence around a transformer and generator near the receiving area of the facility. The transformer and generator were scheduled to be replaced today.

"The inmate on the ladder stepped on the transformer cover causing a grounding effect and electrical shock," Shimoda said.

OCCC personnel, who requested anonymity, said none of the nine to 11 inmates on the work line yesterday was trained or wearing proper protective equipment to be working near a transformer. Such tasks are assigned to work-line inmates because they are paid a fraction of what it would cost to contract the job out, they said.

Responding to the concerns, Shimoda said, "We do use inmates on work lines to save money ... but we do not knowingly put them in danger.

"We feel they are qualified to work in a safe manner. (Yesterday's incident) is truly an accident and not anything that was foreseen," he said.

Reach Rod Ohira at rohira@honoluluadvertiser.com.