# Power Failure or Cold Start Situation in PFMEA

#### ROOTS

##### Involved In Discussions
Hi All,

Can anyone explain what are the current controls to be considered (May be prevention or Detection) during preparation of pfmea for the defects (failure mode) that may occur as a result of line down or cold start situation.

Thanks
Roots

#### John C. Abnet

##### Teacher, sensei, kennari
Super Moderator
Hi All,

Can anyone explain what are the current controls to be considered (May be prevention or Detection) during preparation of pfmea for the defects (failure mode) that may occur as a result of line down or cold start situation.

Thanks
Roots
Good day @ROOTS
It is not possible for "us" to know what controls your organization has or will put in place. The purpose of the PFMEA is exactly that. i.e. What are the RISKS associated with "line down" and/or "cold start"?... Then identify what controls are or will be put in place to mitigate that risk. The abstract "gap" between the risks (and the associated severity) and the controls established, allow you to quantify an RPN or AP number (depending on the PFMEA type you are applying).

For example- if line down = customer line stoppage, then the risk may be significant.
Again, depending on the PFMEA type you are applying...the risk may result in a severity value of "8".
The final RPN or AP # can then be mitigated by the amount of controls in place . Therefore, if a 2 day safety stock is in place, a line stoppage in your facility may only cause an RPN value of 16 or an AP value of "L" (low). If, however, there is little/no control in place, then the risk to the customer may be reflect in an RPN value of 200 or an AP value of "M" (medium).

Hope this helps.

Be well.

#### Bev D

##### Heretical Statistician
Super Moderator
the controls would depend on what failure modes can occur and their possible causes. those are dependent on what kind of thingamajig you are talking about. is this a wave solder machine, a car, a cupola, a nuclear power plant, a cat scan (with a live body in it)...

#### Miner

##### Forum Moderator
Can anyone explain what are the current controls to be considered (May be prevention or Detection) during preparation of pfmea for the defects (failure mode) that may occur as a result of line down or cold start situation.

You mentioned power failure in the title. You could add controls (D) to detect power anomalies that could lead to power failure. You could add controls (P) such as a UPS to prevent total power failure and buy time to safely stop a line without defects.

Cold start can mean a lot of things, so you need to be more specific. One process that I worked with was a hydrogen furnace. It took days to shutdown and restart without damage. So first control was don't shut it down unless absolutely necessary (i.e., rebuild). Second was don't run any product through it until it was fully up to temperature and verified at multiple locations with a temperature profiler. Other cold starts may require actually running product for the equipment to properly warm up. In these cases, this product must be positively quarantined until scrapped or reworked.

#### ROOTS

##### Involved In Discussions
Good day @ROOTS
It is not possible for "us" to know what controls your organization has or will put in place. The purpose of the PFMEA is exactly that. i.e. What are the RISKS associated with "line down" and/or "cold start"?... Then identify what controls are or will be put in place to mitigate that risk. The abstract "gap" between the risks (and the associated severity) and the controls established, allow you to quantify an RPN or AP number (depending on the PFMEA type you are applying).

For example- if line down = customer line stoppage, then the risk may be significant.
Again, depending on the PFMEA type you are applying...the risk may result in a severity value of "8".
The final RPN or AP # can then be mitigated by the amount of controls in place . Therefore, if a 2 day safety stock is in place, a line stoppage in your facility may only cause an RPN value of 16 or an AP value of "L" (low). If, however, there is little/no control in place, then the risk to the customer may be reflect in an RPN value of 200 or an AP value of "M" (medium).

Hope this helps.

Be well.
Good morning Mr.John C.Abnet..

From your reply i could understand the way that i have to go. I can able to manage now as i got some idea.

Thanks a lot.
Roots

#### ROOTS

##### Involved In Discussions
You mentioned power failure in the title. You could add controls (D) to detect power anomalies that could lead to power failure. You could add controls (P) such as a UPS to prevent total power failure and buy time to safely stop a line without defects.

Cold start can mean a lot of things, so you need to be more specific. One process that I worked with was a hydrogen furnace. It took days to shutdown and restart without damage. So first control was don't shut it down unless absolutely necessary (i.e., rebuild). Second was don't run any product through it until it was fully up to temperature and verified at multiple locations with a temperature profiler. Other cold starts may require actually running product for the equipment to properly warm up. In these cases, this product must be positively quarantined until scrapped or reworked.

Good morning Mr.Miner,

Regards
Roots

#### Sebastian

Trusted Information Resource
In my opinion it is worth to mention, that this subject is related to IATF 16949 sections 6.1.2.3 and 8.5.1.4.

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