How to determine which test requires Measurements of Uncertainty?


We are a material testing company so we follow ASTM Standards in testing soils, aggregates, asphalts, and concretes. During the initial audit, the auditor told us that we don't have any record evaluating measurements of uncertainty and reading standards should help us determine which tests require it.

But after reading all the ASTM standards for the tests that we are accredited in, we couldn't seem to find any "statement" that requires the measurement of uncertainty. For the next audit they will certainly look for the files again but I saw this "ISO 17025 Clause 7.6 of ISO/IEC 17025:2017 is applicable, i.e., where a well-recognized test method specifies the limits of the major sources of measurement uncertainty and the laboratory follows the test method and the reporting instructions;". Can I use this as a reason on why we are not evaluating the measurements of uncertainty?

We are following the standards and the standards specifies the limits of measurements (tolerances of equipment which are verified by a third-party calibration provider) and all of our calibrated equipment are within the limits of the said standards.

Also, how do you provide evidence that you are identifying risks to impartiality on an on-going basis? by giving them an updated list?


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Hey, that's two questions. ;)

I believe the standards which build uncertainty set the limits and tolerances of test equipment, the environment in which the test is conducted, etc will allow you to quote your results as is (in accordance with that standard). Those that do not, have to be quoted including measurement uncertainty which you will need to calculate. Have a look at the reporting section of the standards to see what it says should be reported.

Impartiality risks can be identified in a risk register which you then periodically review. For one customer they really wanted to drive this home, so we developed an annual impartiality statement in which staff were required to declare any risks to impartiality. Not sure that this was really needed, but it certainly satisfied the auditors. You could have just had a policy that said staff were responsible for identifying any new or changes to risks as they become aware of them. The nice thing about the form is that you can easily provide evidence. Relying on the policy alone means that unless you get responses from staff, you have no evidence that it is working.
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