Calibration Labels - Original Calibrating Date or New Date?

[Raffy]

Hi Everyone,
Last week we were been audited by a customer and he suggest that during extension of calibration of a certain equipment, we must still use the original date in which it tells the expiring date, e.g. Calibration Date: 06/01/01, New Calibration date: 07/01/01. Instead of the date of new calibration date to be used, we must used the original date. Does it reflected on the new standard (ISO9001:2000)? Is there any clauses wherein we may deviate? Please advice.
Any feedback would be appreciated.
Thanks in advance,
Raffy

[D.Scott]

Raffy - Not quite sure where your customer is headed with this but if we are talking about the calibration label on the equipment, IMHO it should show the date of last calibration and the due date of next calibration along with the initials of the technician. There must also be a unique identifier for the equipment to trace back to calibration records.
That is where there is a requirement that original date of purchase, first calibration, repairs, etc. should be kept.
I would try to get further clarification from your customer on what he is looking for.

Dave

[Jerry Eldred]

Extension of calibration interval in my context is used to temporarily give permission under extraordinary circumstances to use the equipment past it's assigned calibration interval. For example, a unit with a 12 month interval is calibrated on June 15th 2000, and due for re-calibration on June 15th 2001. The user contacts the lab and says it is in the middle of automated testing that cannot be interrupted, and which will complete on July 13th. I review results of a few previous calibrations , and find that the unit has stayed in tolerance for many years. Based on a high confidence level that it will remain in tolerance for the additional one month extension, I add a thirty day extension to the interval.

It is important to still reflect the original calibration date, and perhaps use a special label identifying that this is an extended interval. In no circumstance should the actual calibration date be changed. The label must reflect when the unit was last actually calibrated; that is not negotiable.

[JerryStem]

We sometimes run into the same problem here. Our tech's and customers may not be able to schedule together in a certain month (we do site cal's also).

We have a special procedure where the customer runs a "stability loop" on the instrument (fairly simple procedure) and faxes the results to us. We then issue a decal to place next to the original cert decal that has the original end date and new end date (+30 days). We also issue a certificate that details what we/they did, with dates.

Interestingly, we changed our cert/recal dates to a month/year format & that has reduced the problem considerably. (Gives the customer & our tech a whole month to get together).

Jerry

Raffy,

The customer is always right!

Don't sweat the small stuff. Write a clause into your procedure or instruction that covers calibration date extensions (and follow it).

ASD...

[Trakman]

Jerry,

Good point on the calibration extension. For Raffy, keep in mind that the responsible department defines the interval, ISO does not. The important thing is that an interval is determined. Some equipment may be extended to two years (depending on many factors of course!) but this can still be done. (corrections/beatings/yelling will be tolerated if I am out to lunch...)We recently ran into the catch-22 situation; the customer owned the test gear, but required it to be within calibration. The calib date neared and passed, with numerous requests for approval to calibrate, but was not received. (they are a massive company...) Nevertheless, we still were contractually bound to deliver product using their test equip! The entire situation was completely documented. (very important!) We ended up being forced to utilize the "out of calib" equipment. Yuk!
Trakman

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[Graeme]

Originally posted by Jerry Eldred:
... I review results of a few previous calibrations , and find that the unit has stayed in tolerance for many years. ...

Another thing you may want to consider if you have "many years" of data is to actually increase the calibration interval. If you have the data to back it up and use a recognized method to calculate the new interval there should not be a problem. A side benefit to the customer is that they save money by not having to send the instrument for calibration as often.

You must have enough data to make a statistically significant estimate of the new calibration interval. That can be a problem if you don't have many of a particular model or type. See NCSL RP-1 for very detailed information on this topic.

As for documenting, what we did a a Naval Shipyard (now closed) that I worked in was document the temporary extension in the database, and apply a new label with the work "extended" and the lab manager's initials in the original cal date space, and the new due date in the ... due date space. This label was placed NEXT TO the original one. (The organization I am working with now prohibits extending the due date at all, for several very good reasons that don't apply in most industries.)


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Graeme C. Payne
ASQ Certified Quality Engineer
ASQ_Graeme@yahoo.com

Upon reflection I would like to ammend my previous statement.

-Are there back-up gages available? If no, why not?

-Should this be addressed during FMEA/contract review? Yes

-Is there a robust contingency plan? Should be.

I'm leaning towards the position that extensions should not be "way out" but that pre-planning is the methodology of a company that is pro-active and does the job right the first time.

Considering the variables inherent to floor and lab gages I don't believe that past history is a good reason to let a gage pass calibration dates.

-How many times has a caliper been dropped?
-How many times has the variation in air pressure affected an air gage?
-How many times has the temperature in a controlled lab deviated?
-How many times have gages been stolen and sold at the local flea market? (yes it happens and what is the contingency?)

Just a renewed opinion,

ASD...