ALGOA, Texas -- The mother of Rocky Strength, 30, one of four people killed in a crane collapse, said Monday that the risks of her son's job were always hard for her to accept, KPRC Local 2 reported.

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Marion "Scooter" Hubert Odom III, 41, of Highlands; John D. Henry, 33, of Dayton; Daniel "DJ" Lee Johnson, 30, of Dayton; and Strength, of Santa Fe, Texas, died when a 400-foot crane fell at the LyondellBasell refinery in the Houston Ship Channel at about 1:30 p.m. on Friday. All were contract workers with Deep South Crane and Rigging.

Lisa Schneider has several children who are ironworkers.

"That's why I didn't want to talk to them about it. They were going to be ironworkers anyway. He was so proud of his job. He loved it," Schneider said.

A refinery representative said that 3,000 employees and contractors returned to work Monday and counselors were made available.

Union representatives said death benefits are being paid to the victims' families.

The Occupational Safety and Health Administration said compliance officers were at the refinery on Monday. The results of their investigation could take up to six months.

Workers returned to an east Houston refinery Monday where four contract workers were killed when a massive crane collapsed, KPRC Local 2 reported.

Seven other contract workers were hurt in the accident.

The crane had not been scheduled for anything on Friday, but refinery officials said it was on when it fell. It was capable of lifting 1 million pounds.