Machine Safety: Protection is better than a cure

Can protection be an effective strategy for machine safety or does industry need a cure for hazards to protect employees? Here's why this questions should be asked daily.


Can protection be an effective strategy for machine safety or does industry need a cure for hazards to protect employees? Is this even a fair question?


In my opinion it is a fair question and one that should be asked every day. Here’s why!


First, every potential and existing hazard needs to be identified. Secondly, every identified hazard must be evaluated, scored, mitigated to an acceptable level and documented. This is called the risk assessment process. Throughout this process for each hazard various measures are applied as individual “protections” in order to reduce the likelihood, severity and/or frequency of injury. At some point after all potential protections have been applied a determination is made that acceptable risk has been achieved. And, for this hazard, it can be absolutely be known that some risk still exists. This level of risk is called residual risk.


For any given machine there are typically several hazards. The first consideration for any hazard is to eliminate that hazard by “designing it out”. If you are successful at eliminating this one hazard you could possibly consider that one measure a “cure”. However, that one cure will not eliminate the other hazards on this machine. The goal is to achieve a net effect of reducing all risks/hazards on a machine using the Hierarchy of Measures shown below. This process is designed to achieve acceptable risk levels for all hazards on a machine. 


The Hierarchy of measures are as follows:

1.) Eliminate the hazard – design it out

2.) Isolate the hazard with hard guarding

3.) Add additional engineering, guards, devices, or layers of safety

4.) Administrative controls like – training, signage, assessments, etc.

5.) Personal protective equipment (PPE) like - goggles, gloves, outer clothing, shields, etc.


In conclusion, would you agree that an effective risk reduction strategy includes a combination of “protections” and “cures” for each and every hazard on a machine? An effective analogy for most of us would be air travel. Just think, if the best engineers and innovators developed a solution that eliminated tires going flat during flight, would that be a cure for all hazards of flying? Obviously – no! In fact, every day we all experience residual risk – in various forms!


J.B. Titus, CFSE

Your comments or suggestion are always welcome so please let us know your thoughts. Submit your ideas, experiences, and challenges on this subject in the comments section below.


Related articles:

Machine Guarding & The Hierarchy of Measures for Hazard Mitigation

Machine Safety – does OSHA reference consensus standards for compliance?

Machine Safety: Is OSHA okay with my 'acceptable' risk mitigation?

Machine Safety – consequences of not performing risk assessments!



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