Usage of Calibrated Equipment - Vernier Caliper

[anil123]

The vernier caliper was calibrated and found OK. However it was not taken for the use till its next calibration due date and after the due date it was taken for the use. Does this caliper can be taken as it is for the usage. Please guide.

[Stijloor]

In Reply to Parent Post by anil123

The vernier caliper was calibrated and found OK. However it was not taken for the use till its next calibration due date and after the due date it was taken for the use. Does this caliper can be taken as it is for the usage. Please guide.

If it can indeed be verified that the caliper has not been used (because it was in storage), the calibration due date can be extended and the caliper can be issued for use. Now, if this caliper is used on a very infrequent basis, why not specifying: "calibrate prior to use"? The standard (in 7.6) gives you that option too.

Stijloor.

[NANDAKUMAR_A]

Dear Mr.Anil,

In my view , it is not necessary and again it depends on the duration of storage and preservation.
However for audit purpose we can corss verify any reference value and record before use , to ensure the validity of Calibration.

Nandakumar

[Ron Rompen]

While both Stijloor and Nandakumar are correct, in my experience it is difficult to ensure that the suggested process (extend date, calibrate prior to use, cross-reference to standards prior to use) is consistently followed out, and to provide evidence that it is.

As a general guideline, I would suggest performing the calibration as scheduled; this is not an onerous or time-consuming task, and will (probably) be easier in the long run.

[Stijloor]

In Reply to Parent Post by Ron Rompen

While both Stijloor and Nandakumar are correct, in my experience it is difficult to ensure that the suggested process (extend date, calibrate prior to use, cross-reference to standards prior to use) is consistently followed out, and to provide evidence that it is.

As a general guideline, I would suggest performing the calibration as scheduled; this is not an onerous or time-consuming task, and will (probably) be easier in the long run.

Time and cost should be considered as well.

Stijloor.

[silentrunning]

Could you use this tool and then send it out for calibration / verification? If you quarantined the product until the accuracy was verified, it seems this would be acceptable. Comments?

Also, if you were going to extend the calibration date, wouldn't there have to be a written provision for this in your procedures?

Doug

[DrM2u]

In Reply to Parent Post by silentrunning

Could you use this tool and then send it out for calibration / verification? If you quarantined the product until the accuracy was verified, it seems this would be acceptable. Comments?

Also, if you were going to extend the calibration date, wouldn't there have to be a written provision for this in your procedures?

Doug

Assuming that there is a documented procedure, having a written provision does not guarantee that the procedure is followed (see Ron's comment).

From various practices that I have encountered in the past, there is one that made most sense to me. Some companies (and many calibration software packages) keep records of the verification/calibration date and the date the equipment is placed in use. The verification/calibration interval starts when the equipment is placed in use and is followed regardless of how much or how little the equipment is used during said period of time. The verification/calibration records and results are used to determine any need to adjust the frequency. This way the equipment is not verified/calibrated when there is no need for it (time and cost savings) and is verified/calibrated at established time intervals OF USE to ensure suitability and reliability of the measurement results (part of clause 7.6, I think). Of course, this approach is valid only for inspection & test equipment that does not change its calibration condition over time if not used. A vernier caliper is probably one of the most rugged variable gauges in use.

[dhghan]

We set our caibration due date every 2 years instaed of yearly.This is set after the equipment for 2 continous yearly calbration period show that the accuracy is consistent. Any comments on this?