The tech who previously occupied my role had begun expanding the calibration frequency for some of our gages. The problem is that most of the items were those calibrated from outside sources, so a gage had two calibration stickers: the O.S. calibration company’s and his, which was set for a longer duration. Since the calibrations in question are for the gages used to measure other gages, I am thinking that is a no-go. Thoughts?
This can definitely be a concern, especially for gages used to calibrate other gages.
In most cases, the external calibration should be treated as the official calibration event, especially if it’s coming from an accredited lab with traceability. Having two stickers with different intervals can create confusion and may be difficult to justify during an audit.
While calibration intervals can be extended, that usually needs to be supported by historical data and a documented process within your quality system, rather than applying a longer interval after the fact.
For gages used to calibrate other equipment, it’s generally best to stick with a single, clearly defined calibration due date that aligns with your quality system and the lab’s records.
I’m interested to hear how others are handling interval adjustments in similar situations.
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How we get around that is we use our calibration sticker only- we pull the outside vendors sticker. Then in the GAGEtrack entry, we list the “service date” as the date the gage was actually calibrated by the outside vendor as reference, then put our calibration cycle into the schedules tab. We have also requested to some vendors to not list a due date on the cert as some of our gages are not immediately put into use when they are returned. They are stored and the calibration cycle doesn’t start until the gage is issued. So, our due dates are often different than on a cert.
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Also, in response to the fact you are doing this with “reference standard gages”, if we go longer than on the cert (as in with our back up gage block set that may only be used a couple times a year), we can fill out the appropriate paperwork and with approval from the quality manager, extend a calibration. So, our back up gage blocks that are on a two-year cycle (but was only used maybe 3 times) we got documentation of approval. Then created a calibration and labeled it extend calibration and attached the document to that calibration entry in GAGEtrack.
Hope that helps.
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We have our master set rings on a 5 yr cycle with an outside source. However, we have a visual check set on a 12 month cycle with our lab to ensure the ring has not been damaged in any way.
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We do something similar here too. We will set up the calibration test points to have an atribute check which is basically “outside calibration pass/fail” and an additional check for “visual condition inspection pass/fail”. Then in the notes we have stated “outside cal every 6 years, Visual every 2” . I’ll set the calibration cycle for 2 yrs, and in the notes I’ll put the last outside cal date. This has been seen by the ISO auditors and hasn’t raised any alarms. They sometimes ask me to explain it or show them the gage, but that’s about it.
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We got an opportunity for improvement for this. Even though we had documentation of when the official calibration was, because it wasn’t readily available on the main page of the gage’s entry, they wanted to see a way that could immediately be referenced. So we started listed the official calibration date as service date and then note the date issued (when calibration cycle started) in the notes on the main page (If it was not immediately put into use when returned from calibration).
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We have to stickers, the official A2LA and our in-house verification sticker. ISO17025 states that a gauge must be verified in-between calibrations multiple times. I do 4-month intervals, 2 is multiple. This satisfies the requirement. I use calibrated/certified gauge blocks and weights for our micrometers and balances.
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Our auditor wants to see the sticker on the gauge. They say the technician needs to know if the gauge is in calibration when they pick it up and not to have to go look into the record. I am not sure what ISO17025 has to say on this but would like to know.
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the fact that these are used to verify other gauges that were officially calibrated raises concern for me. We extend gauges we verify with in-house certified standards but never the standards used to verify anything. We have a 2nd set of standards that we rotate them so never have any out. An auditor never raised a question to this practice? And we can only extend our gauges, Instron frames 6 months, if using SQC standard checks or certified working standards.
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All,
Thank you for your help and advice! 
It looks as if things are as I had feared. 
Yes, I def understand the concern for a standard to be extended. The two times I have sent standards out, I ensure all internal calibrations are completed for the time it will be out. As in the case with the gage blocks, in case of need, that second set is there to be used but rarely needed. I have only had to use the second set as reference (not to calibrate) and once pulled two blocks for a sort. I have been here a year and a half and only used it three times.
Same on regular gages, we only extend if proper procedure followed and have a plan in place to calibrate at earliest ability. No concerns from auditors (so far) on extending gages- even that standard.
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Looks like you are addressing it tho, and constant improvement is the goal. 
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