MRO Magazine

Kirk trapped key interlocks enhance lockout tagout

July 13, 2015 – Enhancing lockout tagout procedures with Kirk trapped key interlocks ensures energy isolation procedures cannot be circumvented.


July 13, 2015
By PEM Magazine

Typical industrial equipment may contain hot fluids, blades, fans, pinch points, and moving parts hazardous to workers and other equipment. A written lockout tagout procedure is used to document the steps to isolate the hazardous energy source. Kirk trapped key interlocks can aid in isolating the energy source and the lock and tag can be applied to the interlock.
This partnership between the trapped key interlock and lockout tagout mitigates the opportunity for personnel mistakenly removing the lock and tag, and re-energizing the equipment. The key is removed from the trapped key interlock and is with the person leading the lockout tagout procedure. The equipment cannot be re-energized until the uniquely coded Kirk key has been re-entered into the sequence after all workers are clear from the completed task and out of harm’s way. To further enhance the safety of the procedure, a time delay unit can be added into the process to allow the hazardous energy to dissipate prior to allowing access.
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