Can YOU help? --> Unanswered questions <-- (Other than Marcelo's Informational posts)

Audit and Calibration question - does verification alone meet the requirements?

S

stevew

#1
We verify weight scales each shift. The auditor representing the customer found that to be inadequate and the scales should be calibrated. We maintain verification meets the ISO standard - “calibrate, verify or both."
We always meet our customer requirements but I'd like to know – does verification meet the standard or not? stevew
:whip:
 

harry

Super Moderator
#2
Re: Audit and Calibration question

Some argue that calibration and verification are the same but this is another issue argued in many threads here.

The key words for this issue is in clause 7.6a, 'traceable to international or national measurement standards'. Can your so-called verification meet this requirement? I guess not!

Common practice is to send for periodical calibration by a competent lab to meet this requirement. Subsequent verification which may be done as often as daily (depending on factors such as risk involved, etc) is more a matter of good practice and risk management.
 
Last edited:
#3
We verify weight scales each shift. The auditor representing the customer found that to be inadequate and the scales should be calibrated. We maintain verification meets the ISO standard - “calibrate, verify or both."
We always meet our customer requirements but I'd like to know – does verification meet the standard or not? stevew
:whip:
You can simply verify scales, as you are doing. What was the basis of the evidence of inadequacy the auditor called out? If they simply 'felt' it was inadequate, then that's not good enough to justify you doing anything different.
 
D

David DeLong

#4
Verifying and confirming the calibration of measuring instruments is quite different. Possibly your verifying method is really the confirming of the calibration process. It depends upon what exactly is done.

Let's say that you place a sample of known quality on the scales and the scales read within a set boundary. Possibly, one could even adjust the weight or zero it off. I guess that you could say that this process is similar to zeroing off a dial indicator at the beginning of a shift which is is not calibration but a verification process.

You confirmation of calibration should contain various samples (at least 3) throughout the scale usage range. On a regular basis, place the samples on the scale and read the results. Are all within your scale calibration tolerance or not? That is an example of confirming the calibration of your measuring instrument.

One could also bring in a person from a calibration company to perform the same task with the exception that if the scale was out of calibration, this person could also adjust it to bring in back into calibration tolerances.
 
#5
Before we make this too complex, we also need to understand - in addition to why the auditor make the comment - what these scales are being used for.

What's common practice in calibration and discussions of "confirming calibration" :confused: are misplaced unless we have a good understanding of the use of the scales, first. It seems we ourselves are behaving like the auditor - rushing to judgement before having a complete set of facts. Nothing needs changing until then......

SteveW, over to you.......
 

Top Bottom