In general, the PFMEA should address potential failures that are intrinsic to the process in question. If we include things like power failures that affect the entire facility, we might as well include asteroid strikes. The contingency plan, if properly executed, should address what must happen in production in the event of whatever extrinsic phenomena might occur. It should be assumed that if power outages are recurring phenomena there are plans in place to deal with the potential results.Hello all,
Say we have a plant in Mexico, and once in a while there is power outage.
Must that be taken into consideration in PFMEAs? Or is it enough to cover it in contingency plans?
Thanks a lot!
Manuel
I don't think there's anything to be gained by including in the PFMEA potential causes that we have absolutely no control over. There are not very many manufacturing processes that don't depend on a consistent supply of electricity. That's why things like power outages and acts of nature that have a global effect are best dealt with in contingency plans. That's what contingency plans are for.I have a slightly different take on this.
If the process is dependent on electrical power for important process functions, then power plant failures enter the FMEA as a cause of the process failure.
we have several critical processes where a power disruption (from whatever source) has catastrophic results on the product. we therefore put mitigations in place to reduce the occurrence of disruptions, robust against them, etc.
I have a slightly different take on this.
If the process is dependent on electrical power for important process functions, then power plant failures enter the FMEA as a cause of the process failure.
we have several critical processes where a power disruption (from whatever source) has catastrophic results on the product. we therefore put mitigations in place to reduce the occurrence of disruptions, robust against them, etc.
I agree with Bev on this. The way it was posed by the OP was that this was a common event, not a rare event. Having worked at several companies that have facilities in Mexico, this is a familiar event to me also.
An analogous utility situation for me was air powered torque drivers. Periodically the plant air pressure would drop, which would cause the applied torque to drop also. While not proactively done, we added pressure regulators set below the level of the pressure drop, reset the torque drivers to work properly and added the issue and actions to our PFMEA for the future.
My current company makes a product line that protects against voltage sags, which account for about 70% of power disruptions. The point is that there are often ways to mitigate, if not eliminate, the risks.
How often is one and a while? If it is once a week, I think it should be included. Once a month, probably.
I think severity matters too. If a power failure (regardless of how often one occurs) may cause an event that would cause injury or worse, (severity of 9 or 10 in the AIAG scale), I think it needs to be included in the PFMEA.