The Lockout/Tagout procedure is used in the control of hazardous energy for the safety of employees in industrial and commercial production settings. When equipment is in a ‘Lock’ position, the only restart mechanism is a key possessed by authorized personnel. Equipment that is in ‘Tag’ status is merely paused and labeled with a warning that the machine will remain stopped until the tag is removed. Catastrophic or fatal accidents can occur due to failure to follow procedure by ignoring or defeating the purpose of a tag or during instances where a machine malfunctions. ARCCA has been called upon to investigate such incidents to determine how a particular injury occurred and whether user error or machine malfunction may have been the cause. This work requires collaboration between our failure analysis engineers and our biomechanical engineers.