Trapped Key Systems

Trapped-key interlocking uses locks and keys for sequential control of equipment and machinery to ensure safe operation. The safe sequence is created through a transfer of physical keys that are either trapped or released in a determined order, usually starting with the isolation of a power source that can then be used to gain access through a gate to a high risk area. Different types of keys ensure that the initial key cannot be returned until the original personnel are clear of the hazard and all keys have been returned in sequence.