When to take action if an FMEA RPN number is high?

[falconer65]

When a company I worked for went from QS to TS, I was tasked with redoing the FMEA's. The the audit found the RPN's were ridiculously low and did not reflect the defects being recorded. Using data from the previous 5 years I set up the first FMEA. In the meeting to go over the FMEA everyone was shocked. I showed the data to back it up and the AIAG manual to show it was done correctly. Managements decision was to cut the occurrence rate so we showed the RPN above 100 on only a few items they chose. That was a tough day.

 

[Stijloor]

When a company I worked for went from QS to TS, I was tasked with redoing the FMEA's. The the audit found the RPN's were ridiculously low and did not reflect the defects being recorded. Using data from the previous 5 years I set up the first FMEA. In the meeting to go over the FMEA everyone was shocked. I showed the data to back it up and the AIAG manual to show it was done correctly. Managements decision was to cut the occurrence rate so we showed the RPN above 100 on only a few items they chose. That was a tough day.

Thanks for sharing your FMEA story.

Yes, and that's how the sad FMEA game is played. Hung up on RPN's.

The current AIAG FMEA manual provides somewhat better guidelines with respect to FMEA analysis, prioritization and possible actions to be taken.

Stijloor.

 

[Jim Wynne]

From various experience , 100-150 is a common value but there is not a precise rule.
However , you should take action when severity is classified 9 or 10

Taking action on things with high severity ratings won't help anything if the occurrence (especially) and detection ratings are low.

 

[qusys]

Taking action on things with high severity ratings won't help anything if the occurrence (especially) and detection ratings are low.

Hi.
This is related to my work experience ( internal auditor, second part auditor) and some benchmarking done.
There were also some requests from Customer in this sense: provide actions in case of high severity

 

[qusys]

Why and according to who? Qualify the statement.

This was related to some on the field experience ( benchmarking) as well as precise Customer requirement in this sense.
However it is not a rule as I said in the post

 

[AgnieszkaSz]

I am a bit confused. Shouldn't we use the manual? In Chapter IV, in section "Determining Action Priorities" there is an unequivocal statement that the cases with highest severity (9 or 10) go first; for severity 8 or less, the sorting criteria are occurence or detection. In next section there is a statement in bold that the use of RPN threshold is NOT a recommended practice for determining the need for actions; then the explanation why follows.

 

[Rand T]

Not all industries are required to follow the AIAG criteria. FMEA's are broad based and can be applied to many different processes.

Also regarding the actions taken on Severity of 9 & 10. Since the severity is the one ranking that can't be reduced without a design change, any actions will only have the effect of reducing the occurance or detection. If those are already at very low rankings, than realistically there is probably little more that can be done.

 

[TShepherd]

TR Shepherd here,

My experience has shown me that selecting an RPN bogey doesn't make a great deal of sense.

Most knowlegable companies now use the rolling top 3 or 5 or 10 whatever within a FMEA and the number selected is based on the actual RPN values and a number of other things including available resources.

The RPN number only has relative value within a specific FMEA and to the team that is using the document.

The final word comes from your customer, if they have a customer specific target regardless if it makes sense or not - that's the number - adjust accordingly.

Tom

 

[Sturmkind]

I agree with many of these posts. Some commodities that are directly safety related (brake systems, airbags, seat belts, etc.) with major design changes or new designs will have very high RPN numbers until testing allows for a reduction in SEV, OCC, or DET.

Chrysler LLC in the 'Blue Dot' series of documents always reviews the top 5 RPN numbers regardless of numeric value.

GM requires an RPN reduction plan regardless of numeric value.

Arbitrary values can limit both continuous improvement and the 'flinching' mentioned earlier to keep the value below a set ceiling.

 

[playhard]

We conduct annual reviews or RPN reduction teams to review all PFMEA's and focus on the top 5 what ever the number is.

We also will review the top 5 when we use the PFMEA in our corrective action reviews.