ISO/IEC 17025 Calibration or Verification
I have a lab that received a non compliance because they issue Verification report for their micropipettes.
The verification is performed on a balance which is itself controlled (but not calibrated because they are on an island without calibration services for the balance).
The balance is controlled with calibrated weights (E2). The weights certificates are interpreted to ensure that the E2 category is respected.
The verification of the micropipettes is performed according to the principles of ISO 8655.
ISO 8655-2 states that you can consider :
- conformity tests (calibration, performed by an accredited lab)
- user test : check of the accuracy (among other points)
The lab controls the performance of the micropipette according to the requirements of ISO 8655-2, point 7.2 (for instance)
The non conformity issued by the auditor is "you perform calibration, not verification, so, you have to calculate the uncertainty and take it into account for the conformity assessment"
My point is :
- can the lab stay on the position that it is not calibration, it is verification, therefore no uncertainty calculation/estimation is necessary
- the norm makes a difference between calibration and verification, 6.4.4, 6.4.6,...
- the VIM vocabulary makes a clear distinction between calibration and verification
- ISO 8655 does not specify that the uncertainty has to be taken into consideration to assess the conformity...
Otherwise, I would recommend to the labs to calibrate every two year (see rules in ILAC G24 to justify the intervals) and please, do not perform verification if the auditors impose a determination of uncertainty
Last point, I saw some "recent" calibration certificates of micropipettes issued by accredited labs. If you take into account the uncertainty to check the conformity, the uncertainty was quite high (50 % of the tolerance), meaning that there is a lot of micropipettes on the market that should go to the trash (or adjusted but this is another topic)
So, do you think that the lab could stick to the fact that they do not perform calibration ? Any other argument ?
Calibration or Verification