To answer your first question – yes it is permissible to conduct internal calibration on measuring devices, as long as you hold a current, valid and traceable reference standard for the measurement devices being calibrated. The normal practice under ISO 9001 is to calibrate at three points along the range of the device, in controlled environmental conditions. As an example, a 1” mic would be verified at .125”, .450”, and .875”. This assures that the gauge is accurate across its range of measurement.

With the second half of your question, you’ve changed topics. Now we apparently need to deal with 17025, as this may be a requirement of your AS 9100 program. If this is the requirement, you need to set up your lab to meet that standard for environmental conditions, and to ensure that recording of “as found” & “as left” dimensions is done in finer increments, along with the amount of error at each interval checked.

17025 is normally reserved for firms marketing themselves as a calibration facility for other businesses. The certification process is very expensive. Please review your customer’s requirements to be sure you need to be certified to this Standard. If not, you probably only need to become compliant to that Standard. In that case, you need to implement all the required measures, but then prove your compliance by a diligent and detailed internal audit, followed by a self-declaration of compliance.

This will likely require a substantial investment in a climate controlled space for the calibration process, improved traceability / recall controls, improved recording of findings / results, etc. Review these costs carefully – if you are only calibrating a small number of devices, it may prove less expensive to continue to use an external lab for calibration.

– Ted Uffen, BRC Quality Consultant