According to a U.S. Occupational Safety and Health Administration document, a 2-inch metal pipe fitting blew off a valve and hit an employee in the head, killing him.

In the citation issued on May 12, 2015, OSHA said, "[Halliburton] did not furnish employment and a place of employment which were free from recognized hazards that were causing or likely to cause death or serious physical harm to employees in that employees were exposed to struck-by hazards associated with working in the red zone of the [gas] well."

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"Employees remained in the red zone while equipment was pressurized up to 3500 psi [pounds per square inch]. This condition exposed employees working in the red zone to struck-by hazards as a result of an explosion," the OSHA report said. In "abatement notes" on how Halliburton should reduce well-site hazards, OSHA said, "Frozen plugs should be allowed to thaw at a normal rate. Steam or hot water should not be used to thaw plugs…Freezing operations should be under the direct supervision of a qualified person."

The United States Occupational Safety and Health Administration (OSHA) has fined Halliburton seven whole thousand dollars for the safety violations that lead to the death of one worker at one of their fracking sites in Weld County, Colorado. OSHA found that:OSHA seems to like that $7,000 number. They fined a Halliburton plant that almost blew up a town a whopping $49,000 a few months back —$7,000 for every person on site at the time. In OSHA's defense, when you go to their website it doesn't look like they have much time to worry about fines, they're too busy dealing with the oil and gas industry constantly violating the law.