The following 3 case studies illustrate the importance of lockout / tagout programs. They also discuss the unfortunate consequences of not having or not using lockout / tagout.
Case Study 1:
Employees were performing repairs on an 8-ft-diameter pipeline that carried hot oil. They had properly locked and tagged pumping stations, pipeline valves and the control room prior to beginning repairs. When the work was completed and inspected all lockout / tagout safeguards were removed and all elements were returned to their operating state. At this point, control-room personnel were alerted that the work was completed and they were requested to start up the system 5 hours earlier than was scheduled.
Two supervisors not aware of the early start-up decided to inspect the repairs themselves. They were required to walk inside the pipe with lights in order to perform the inspection. They did not perform any lockout / tagout procedures for the inspection process. They also neglected to notify control-room personnel of their last-minute decision to inspect. As the control-room operators started the system as instructed, oil began to flow through the pipe killing the two supervisors.
Case Study 2:
A 52-year-old welder died when he was crushed to death by a hydraulic door on a metal shredder. The employee was attempting to remove a jammed piece of metal from the hydraulic door on the shredder when the item causing the jam fell away and the door suddenly closed on him. The system's energy had not been released and the door had not been blocked open.
Case Study 3:
A 35-year-old employee was changing blades on a cutting machine at his place of work in New York. According to the police report, another worker accidentally hit the wrong switch and powered on the machine. The 35-year-old employee was killed instantly. Both workers were experienced, long-time employees of the company.
By providing lockout / tagout programs, training and enforcement these incidents and many others can be avoided. Lockout / tagout is not cost prohibitive. However, it does require management and employees to be diligent.