Say what you do and do what say—nothing more.

J. Stephen Van Heyde is a lawyer with Baker & Hostetler LLP in Columbus, OH. As legal counsel for the American Measuring Tool Manufacturers Association (AMTMA) he recently gave a presentation at that group’s spring meeting, held March 6 to 8 in Phoenix. The speech dealt with the language used in calibration reports. He focused on the idea that while the measurements referred to in typical calibration reports might be quite precise, the language used in the reports was often quite the opposite. This disparity could create misunderstandings which, in the hands of a competent litigator, could come back to haunt those who issued the report.

Playing devil’s advocate,Van Heyde took various words and phrases commonly found in calibration reports and explained how a lawyer could interpret them. I don’t mean he twisted the words to something that no longer resembles reality. The words he used reflected the legal reality.

He began with the term, “certificate” and it went downhill from there. He noted that these words imply that any and all tests or measurements that could be done were done. Such is not usually the case. To use these words without all the testing being done would require a lot of disclaimers in the calibration report. He cautioned everyone at the AMTMA to avoid “certifying” anything!

Issuers and readers of calibration reports could learn many technical lessons from this presentation. Here are some examples of what I mean:

Size.

We all know what this word means, don’t we? On the surface it seems straightforward, but the catch here is that we rarely determine the “size” of a plug gage, for example. We take diameter measurements, for example, the length between two points. The actual size of the gage will be determined by those diameter measurements combined with other values such as roundness and straightness.

Pitch Diameter.

Using this term on a calibration report would seem to solve the potential problems in using the word, “size.” Or does it? I would estimate that more than 99% of the reports that use this term are really referring to “groove diameter” or “simple pitch diameter,” not “pitch diameter” as defined in most formal standards. Corrections for variations in linear pitch and angle are required to determine the actual or functional pitch diameter. There is much work to be done to declare a “pitch diameter,” which requires corrections for overall geometry.

These additional measurements are rarely done because the average calibration laboratory does not have the equipment. And, the average customer would not pay the price to get a more complete picture of a thread plug gage, especially when such a calibration cost would probably exceed the price of the gage. When wheels start falling off products, measurement matters may be examined, but by then it could be too late. The lawyers will move measurement and calibration issues from the inspection department to the courtroom.

Opinions.

This is an area where accreditors of calibration laboratories, such as the American Association for Laboratory Accreditation (A2LA) share Van Heyde’s concerns. They have clear instructions: Keep opinions off the reports. If a customer has requested an opinion, the A2LA procedure is that such an opinion be expressed in a separate document without the A2LA logo on it. They know a minefield when they see one!

One could retreat to the National Conference of Standards Laboratories International or ISO documents for technically correct language and refer to the “value of the measurand.” Somewhere you’d have to indicate that this might not be the “true” value, which would probably lead to further discussion. Manufacturers looking for “yes” or “no” answers to questions such as, “Is the damn thing any good or not?” may not be impressed by such discussions.

I think I’ll leave this before I get in any deeper. The best advice is get the dictionary out, only report tests and measurements that have actually been done, and watch the words you use to describe what has been done and the results. Keep your opinions to yourself and take Van Heyde’s advice, “Don’t certify anything” unless, of course, your metrologist has a law degree.

On the advice of counsel, be advised that the author of this column may or may not exist and that no known person is responsible for anything herein. A named author-type person will appear next month after his assets have been moved offshore.

Hill Cox is President of The American Measuring Tool Manufac-turers Association (AMTMA) and is chair of its technical committee. He is also president of Frank J. Cox Sales Ltd. (Brampton, Ontario, Canada.) He may be reached at [email protected].

While the measurements referred to in typical calibration reports might be quite precise, the language used in the reports was often quite the opposite.