Companies on this year's list were chosen based on recommendations by industry professionals, recognition by industry associations, participation in programs such as OSHA's voluntary protection program, state and local awards, and Occupational Hazard's research into occupational health and safety philosophy

Conco ranked as the safest major energy company in the United States according to the American Petroleum Institute's latest benchmarking survey of occupational injuries, illnesses and fatalities in the petroleum industry.

"This honour reinforces our long-held belief that safety is the right thing to do," ConcoPhillips manager for safety Steve Brouillard said.

"Conoco and Philips Petroleum Company recently completed their merger to become ConocoPhillips. The new company embraces a long held tradition of putting safety first in every operation.

"In fact, the values of the new company spell SPIRIT, and that S stands for safety. We believe that any job worth doing is worth doing safely."

Companies were chosen for support of management for safety; commitment of employees; supervisors and managers to safe operations; the willingness to benchmark with other companies to provide a safe work environment; and humility to admit they could do safety better.