Skull fracture and intracranial injury

An employee was removing a pipe cap from a header on a riser station as part of an installation of a new fire and sprinkler system. The employee was utilizing a sprocket to remove a bolt on the pipe cap, which was 8 inches in diameter, 1/2 inch to 5/8 inch thick, and weighed 12.7 pounds. Because the valve had not cracked, the pipe cap was under pressure of approximately 80-115 psi. The pipe cap struck the employee and rendered them unconscious. The employee suffered brain bleeding and fractures to the skull, face, and nose that required hospitalization.