Do I need to perform Gage R&R on a Digital Temperature & Humidity Gage

[bstowers]

I have a digital temperature gage (temp/humid), it is permanently in place, never to be moved. Do I have to perform gage R&R, if so, how? If not, where can I find the supporting evidence in the MSA 4th Edition?

 

[WCHorn]

We have a couple of the same instruments in our calibration lab and testing lab. No automotive customer or ISO/TS 16949 auditor has ever required a GR&R on it. It just needs to be calibrated, in my opinion.

We do have some portable contact digital thermometers that we assess with GR&R. That's because the results can vary depending on the operator (probe time constant, length of time on the surface and how well the probe contacts the surface). We do it on our own behalf; no auditor required us to do it.

 

[bstowers]

Thank you for your response! That assures me what I am doing is correct, but my biggest struggle is finding the evidence to support our opinion. I've tried reading the MSA 4th Edition to get proof, but I'm just not sure if I'm seeing it... Just incase auditors ever do ask.. I would need a solid answer.

 

[Statistical Steven]

I have a digital temperature gage (temp/humid), it is permanently in place, never to be moved. Do I have to perform gage R&R, if so, how? If not, where can I find the supporting evidence in the MSA 4th Edition?

First, what is the digital thermometer used for? If it sits on a wall in a lab to monitor the temp/humid, then calibration is your MSA per se. MSA are done on measurement systems (people, procedure, equipment, etc.). The way you describe it, it just a gage, under calibration and not a measurement system.

 

[WCHorn]

Thank you for your response! That assures me what I am doing is correct, but my biggest struggle is finding the evidence to support our opinion. I've tried reading the MSA 4th Edition to get proof, but I'm just not sure if I'm seeing it... Just in case auditors ever do ask.. I would need a solid answer.

I have always believed that MSA is applicable to measurement systems that assess product conformance. I can't find that in writing, but in the Purpose statement of the MSA manual, it clearly states that MSA's "primary focus is measurement systems where readings can be replicated on each part."

That would seem to exclude devices such as temperature and humidity monitors. There's only one operator and one "part," so MSA can't be invoked. That's a stretch, though, and I hope the AIAG can be more specific in future editions of the MSA manual.

 

[deven_17]

Hi,

For such Devices, MSA study can be done for Bias, Linearity & Stability. Calibration is the process to be used to come out of the variations mentioned above.

Thanks,
Deven Malhotra

 

[bstowers]

Yes, that is all it is used for, sitting on a wall monitoring temp/humid.
Thank you for the input!

 

[bstowers]

Thank you WCHorn! That does make more sense now stated that way, thank you for your help!

 

[Chinese Michale]

HI

The gage of temperature and humidity is belong to monitor device. MSA is aim to measure device.

 

[JessLove]

Hi,

For such Devices, MSA study can be done for Bias, Linearity & Stability. Calibration is the process to be used to come out of the variations mentioned above.

Thanks,
Deven Malhotra

I have a similar question...

I have temperature and pH being measured continuously inline on several pieces of equipment. Because those items are listed on our Control Plan we had an Auditor cite a finding because there were no MSAs performed on them. How do I perform an MSA for a probe that has no operator influence and is measured automatically?

I have calibration data but the auditor was not satisfied with that.

Thanks

Jess