Safety Standards

Safety Standards

Interlocking is accepted by safety, insurance, and standards authorities throughout the world as the most reliable and cost effective way of guarding against operator error. The utilization of trapped key interlocks is supported by the following standards and regulations:

United States

OSHA 29 CFR 1910.333

Sets forth requirements to protect employees working on electric circuits and equipment.

“This section requires workers to use safe work practices, including lockout and tagging procedures….exposed to electrical hazards”

OSHA 29 CFR 1910

Process safeguarding is substantially different than machine safeguarding… process safeguarding is concerned with the safety of machinery and industrial processes during periods of service and maintenance.


Gives provisions of alternative control of hazardous energy in robotic applications within Industrial Robot and Robot Systems Safety Requirements.

ANSI/ASSE Z244.1-2016

The revised Lockout/Tagout (LO/TO) standard, defines a comprehensive safety program… Trapped-key interlock Safety switches using a trapped or captive key system ensure that a predetermined sequence of events takes place.