The company was charged by Alberta Occupational Health and Safety with one count of failure to ensure the health and safety of its workers when Nick Ryan, 28, was killed on a rig at a site in northern Alberta.

Ryan was preparing to ­attach a 5000-pound hydraulic wrench to a rig when a co-worker turned the hydraulic pumps off.

He was beneath the iron roughneck when the wrench jaws dropped to the safety stops, striking him on the head.

Ensign