Machine Safety - Hard Guarding Is Best - Right?

While hard guarding can be best for machine safety in some applications, a risk assessment will help assess which technologies should be applied to achieve tolerable risk. This can be where trouble often begins.


We’ve certainly come a long way over the past fifty years regarding machine guarding. Those of us with some grey hair have witnessed the introduction of electrical, electronic, and even software based devices for machine guarding. But hard guards continue to be the base line for “some” regardless of the innovation of technology for safety applications. I recently wrote a blog titled, “Updating Minds About Machine Guarding” to address the adoption of technology issue. However, the central machine safety question still remains:

Hard Guarding Is Best - Right?

Well, quite frankly hard guarding is best some times! A risk assessment will actually help answer this question and the flow charts actually suggest that first steps are to design out known hazards and secondly to apply mechanical guards to achieve tolerable risk. At this point some may say, “job well done”! On the other hand, not so quick, because this is where trouble often begins. A complete risk assessment looks at a machine 24/7. This includes; maintenance, clean-up, set-up, adjustment, clearing, and other operations where hard guards are often removed. In these cases the risk assessment may identify intolerable hazards or risks in these other modes of operations other than production modes. To identify if “other technology” may be needed to provide tolerable guarding 24/7 for your machine a whole new concept may have just entered the room.

The elephant in the room now just may be called “Safety Culture”. Safety Culture will not be found in; industry standards, it’s not covered by the risk assessment, it’s typically not found in the safety policy manual (if there is one), and it’s not taught in the engineering class room. However, it’s what drives the answer to this machine guarding question!

Where do you think the “Safety Culture” elephant in the room comes from or if it even exists?

Submit your ideas, experiences, and challenges on this subject in the comments section below. If your browser doesn't show a comments field, click on this link and scroll down: Machine Safety blog: Hard guarding is best, right?

Also see related articles:

How To Integrate Safety

Updating Minds About Machine Guarding    

Contact: for “Solutions for Machine Safety”.

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