Trapped Key Interlocking

What are Trapped Key Interlocks?

A trapped key interlock is a safety device applied to two or more moveable parts, preventing (or allowing) a movement or operation of one part only when another part is locked in a predetermined position. Castell’s trapped key interlocks operate on the principle that the key can be removed only when the locking bolt is in a predetermined position.

The Castell interlock is used to protect personnel and equipment, with the goal of eliminating errors that can occur when it is necessary to obey a sequence of predefined operations. The Castell system prevents anyone from trying to circumvent the default and crucial to the safety of the procedure sequence. The Castell interlocks can be mounted directly on the equipment, ie, the system is fully integrated and simple to operate.

Why use a Trapped Key Interlock System?

  • TO PROTECT personnel from hazards by ensuring predetermined sequences of operations are followed
  • TO PREVENT loss of operations and setbacks due to equipment damaged by mis-followed operations
  • TO PROVIDE risk control; understanding that everyone has the right to be safe at work!

Installing a trapped key interlock system ensures a predetermined sequence of events is followed. Whereas Lock Out – Tag Out (LOTO) provides a visual warning and some protection, a trapped key interlock system physically prevents a specific set of actions until the previous action(s) have been completed. Checkout the video to learn more: