16th September 2020 by Greg Santo
Lock-out/Tag-out, technically called ‘The Control of Hazardous Energy’ by OSHA, is a combination of engineering and administrative controls. When the energy source is prevented from causing harm, or locked out, that is the engineering control, and the tag-out is simply a communication tool meant to convey why the lock-out has been performed.
Imagine if you will, a workplace setting where a series of offices has ceiling mounted fluorescent lighting, and one morning one of the lights goes out. A work order to the facilities manager will take several days before they respond. Charlie is assigned to that office, and he fancies himself as a handyman, after all, he can fix just about anything, and that light just can’t wait. He goes to the maintenance department and gets a new luminaire for his office.
Although he has not been trained in the Control of Hazardous Energy, he knows that he needs to turn off the circuit breaker to his office which he does. He does not have a lock to secure the circuit breaker or a tag to communicate his activity. Charlie then climbs the 12-foot ladder and proceeds to change out the defective light. He loosens the screws holding one side of the light and then disconnects the wire nuts from the hot, neutral, and ground wires and descends the ladder. Pretty good yeah?
What Charlie does not know is that Susan, the administrative assistant, in another office has a proposal that has a noon deadline that must be met, and her power just went out to her office and specifically her computer.
Frantically she calls Fran, her supervisor, who goes to the electrical panel and turns the circuit breaker back on so that Susan can meet that deadline.
Charlie now has the base to the new light and is ready to hang it from the ceiling, he climbs the ladder and hooks one end of the light. The next step is to reconnect the wiring before securing the light to the ceiling with screws.
As Charlie grabs the wiring … SHOCK! … The shock causes him to fall from the 12-foot ladder and he breaks his leg as he lands on the floor. Sad as that outcome is, it could be much worse. He could have received a shock through his heart causing ventricular fibrillation, a type of cardiac arrest. Without prompt response with an automated external defibrillator (AED), Charlie would have died.
Charlie recovered from his broken leg and his employer scheduled Control of Hazardous Energy for Affected Persons training. Charlie, Fran, and Susan joined their co-workers for this class, and now they know why they need lock-out/tag-out.