What is the recommended calibration frequency for gage blocks?

[mcowan]

Currently my company is looking into making adjustments to our calibration frequency for our gage blocks. We have two sets that are for QA use only and are mainly used only for calibration of other pieces of equipment with in our company. This being said they have little exposure to wear and tare. Is it acceptable to have both sets put on a 5 year calibration frequency or is it recommended to have the max frequency at every 2 years? Any information you can give me on this topics would be greatly appreciated.

[bobdoering]

Here's the thing...you might not wear these blocks that much in a laboratory environment for calibration. But, the other risk is that something does happen to a gage block (and is usually a popular one) and now you have 4 years of suspect calibrations.

What do you do then? Recall product? After 4 years? How do you explain the problem to a customer? That is your risk of getting greedy with the calibration extension.

If you have 8-10 years of solid evidence with a gage block set that the wear can be projected to a 5 year calibration...well, then, maybe... But, consider calibration an insurance payment. You don't have to do it...but what is the risk if you don't? Can you afford that risk?

[mcowan]

That is a definite problem and we will have to take it into consideration. We are trying to cut corners, but probably shouldn't cut too many. Thank you for your input!