Transferring Calibration Certificates

[KShannon]

Typically we calibrate all of our manufactured products in-house to known traceable standards. We are developing a new product that would have extensive capital costs if we were to purchase the equipment to calibrate it ourselves. We have an equally expensive option to send out each product to be calibrated by a third party. The supplier of the sensor which is the main component in the product can supply us a with a calibration certificate. If we can prove the inherent design of the product in no way alters the performance of the sensor, can we simply translate the sensor calibration data to our own certificate. Incidentally, we will have the capability to check each sensor against other known standards that are approximately as accurate. Unfortunately these other standards do not meet our corporate target of a 4:1 ratio.

 

[Al Dyer]

Any chance you could simplify your quaetion?

 

[KShannon]

Sorry for the confusion ... what I want to know is simply whether or not I can transfer calibration test results from the manufacturer of a part onto my own certificate of calibration without duplicating the actual test.

 

[D.Scott]

IMHO I wouldn't think so. First, if the certificate were from your company, you would be expected to have all the test data and be able to meet all the requirements of 17025 pertaining to the calibration. Your certificate would have to list the name and address of the lab who did the calibration and the location where the calibration was performed.

There could be a way around this but I can't see it. It would seem easier to me to simply supply the sensor supplier calibration with the product. If the sensor is the part that gets calibrated and it is proven by your expensive testing that the calibration isn't changed by your inclusion in a product, why would you re-calibrate it? If there is a doubt as to the state of calibration after you do your part, work with the supplier to establish a method of verification (not a calibration) before the item is shipped.

Down the road when the end user needs to re-calibrate the sensor, who will he call, you or the supplier?

I trust the pros here will put us on the right track if I am wrong here.

Dave

 

[Ryan Wilde]

Actually, 17025 is very clear in that you must state on your certificate that these tests were subcontracted.

But since you are a manufacturer calibrating product, I doubt that ISO 17025 is what you are trying to comply with, rather ISO or QS 9000 (correct me if I'm wrong). Neither of these standards has any direction involving this particular situation (ISO 9000 defers to ISO 10012, QS9000 requires that any calibration supplier be ISO 17025 [Guide 25] accredited). So I guess what you are stuck with is, if you are:

ISO 9000 registered, prove that it has no effect on the calibration, put it in writing, keep it on file, check it every so often, and document what you are doing;

QS9000 registered, make sure your supplier is either accreditied to ISO 17025 or has a handy dandy OEM waiver that AIAG is so keen on, and again, prove no degradation in writing;

ISO 17025 accredited/compliant/whatever then go through the same proof process, and make sure your supplier is accredited as well, and state on the certificate that "these tests were subcontracted to XXX Inc.", or possibly "these tests were performed by the manufacturer of the sensor", or any wording that clearly states that the calibration was not performed by your company. The reasoning is supposedly to do with traceability.

Hope this helps a bit.

Ryan

 

[KShannon]

Thanks for the great input. It's nice to see that a common sense approach is potentially allowable (our Engineering staff will be shocked!) For the record, our company is currently seeking ISO9001 registration and will be looking at ISO Guide 25 next.