Interlocked gate testing

Did you know that inter­locked gates require stop­ping per­form­ance test­ing?

Machinery needs to be able to stop in the time it takes a per­son to open the guard and reach the haz­ard. If the dis­tance from the guard open­ing to the haz­ard is short enough that a per­son can reach the danger point before the haz­ard can be con­trolled, the guard is use­less. The res­ult­ing situ­ation may be worse than not hav­ing a guard because it’s pres­ence leads to a false sense of secur­ity in users.

Test the stop­ping time of guarded haz­ards and make sure that guards are far enough away from the danger zone to be effect­ive. For more on stop­ping per­form­ance require­ments, see CSA Z434, EN 999 (soon to be replaced by EN 13855:2010), and in the USA, 29 CFR 1910.217(h)(9)(v).

Download ISO Standards
Download IEC stand­ards, International Electrotechnical Commission stand­ards.
Download BSI Standards (British Standards Institution)
Download ANSI stand­ards

Need help with stop­ping per­form­ance test­ing? Contact us!

Author: Doug Nix

+DougNix is Managing Director and Principal Consultant at Compliance InSight Consulting, Inc. ( in Kitchener, Ontario, and is Lead Author and Managing Editor of the Machinery Safety 101 blog.

Doug's work includes teaching machinery risk assessment techniques privately and through Conestoga College Institute of Technology and Advanced Learning in Kitchener, Ontario, as well as providing technical services and training programs to clients related to risk assessment, industrial machinery safety, safety-related control system integration and reliability, laser safety and regulatory conformity.

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