Our QMS and SOP state “Personal instruments are not to be used for final verification purposes”. In discussions with our Mech Dept, they use personal tools (specifically micrometers) which are checked to an externally calibrated set of standards prior to each use. Machinists don’t feel that micrometers or calipers should be included in the above QMS/SOP statement. These personal tools are calibrated in house annually and internal forms capture the calibration data. We are currently looking at either changing our QMS/SOP language or ensuring a better awareness of quality requirements for final verification.
My question is: if there was ever an issue with customer property and it was discovered that a personal tool was used for final verification, who could be liable for this? Could the liability ever be on the employee because it was a personal tool, or does liability always stay with the company? Does the company take on liability by endorsing calibration of personal tools?
Interesting series of questions! Let’s see how best to answer them.
In all cases, the company has full liability for any work done under contract to the firm. By using personal tools to conduct measurements, employees are unnecessarily exposing themselves to the potential for liability, if the measurements are found to be in error as a result of a calibration problem. This is why we tend to discourage the use of personal tools, unless there is a record of calibration.
It is normal practice for any trained machinist to check the tools to a Reference Standard prior to use. If the device is used to perform a check of a set-up parameter, under ISO 9001, it technically does not require calibration, although this is considered to be a “Best Practice”. Calibrated devices are required for the conduct of measurements involving the acceptability of product.
Staff are checking the mics prior to each use – is there a record of the check? If so, no problem. No record, potential issue.
If the Standard is calibrated and traceable, then we are halfway there. If they record the check conducted prior to taking the measurement, there is no issue at all. Some small shops prefer this method of conducting measurements, as it removes the need to routinely calibrate equipment that may not see usage on a regular basis. They even go so far as to track the calibration status of the reference standards issued to or held by each worker.
If the mic is being used to measure product and make the decision to either accept or reject the product, it must be calibrated, traceable, and a record of the check must exist. If you are calibrating personal mics annually, and the record is available proving that point, there is no problem in a calibration context.
Management then needs to make a decision as to whether or not they are going to control and allow the use of personal micrometers in the measurement of product. Once a final decision is made, enforce it. Several shops with whom I have worked have ended up taking one of 3 courses of action – 1) rolling all personal tooling into the calibration system, 2) requiring personnel to take personal tools home, or 3) marking them all “reference only”, never to be used to measure product. The ability to enforce this becomes the next issue.
Hope this helps. Good luck!
– Ted Uffen, BRC Specialist