What kind of information needs to be in a calibration record?

[dwperron]

So you're saying that verification is a result of calibration?

What I am saying is that Metrology is a precision business.
Our language often needs to be just as precise.
There is a difference between calibration and verification.
Those differences get lost because we are careless in how we use the terms. That leads to confusion.

Probably the best example of this is specification, tolerance, accuracy, and uncertainty. They all mean something different, but they are tossed around as synonyms, leading to confusion.

 

[Jim Wynne]

What I am saying is that Metrology is a precision business.
Our language often needs to be just as precise.
There is a difference between calibration and verification.
Those differences get lost because we are careless in how we use the terms. That leads to confusion.

Probably the best example of this is specification, tolerance, accuracy, and uncertainty. They all mean something different, but they are tossed around as synonyms, leading to confusion.

"Specification" and "uncertainty" are used synonymously? If you perceive a difference between calibration and verification, it's because you're using your own definitions, or definitions that someone else uses and you've personally adopted them and now expect the world to adopt them too. It doesn't work that way. Here are some examples of calibration that don't fit your definition(s):

Self-calibrating thermometer

Self-calibrating scales

Calibrate before each use

In that last example, when making a very close-tolerance measurement with say, a micrometer, it's always a good idea to pull out the gage blocks and verify that the mic is reading accurately. That's a verification, but it's also synonymously an act of calibration.

When you use an eccentric definition for any word(s)--one that conflicts with standard dictionary definition--it needs to be made clear to everyone that the dictionary has been thrown out the window and the eccentric definitions are to be considered normative. There's nothing necessarily wrong with this, but in our business engaging in Humpty-Dumptyism must always be avoided.

 

[dwperron]

"Specification" and "uncertainty" are used synonymously? If you perceive a difference between calibration and verification, it's because you're using your own definitions, or definitions that someone else uses and you've personally adopted them and now expect the world to adopt them too. It doesn't work that way. Here are some examples of calibration that don't fit your definition(s):

Self-calibrating thermometer

Self-calibrating scales

Calibrate before each use

In that last example, when making a very close-tolerance measurement with say, a micrometer, it's always a good idea to pull out the gage blocks and verify that the mic is reading accurately. That's a verification, but it's also synonymously an act of calibration.

When you use an eccentric definition for any word(s)--one that conflicts with standard dictionary definition--it needs to be made clear to everyone that the dictionary has been thrown out the window and the eccentric definitions are to be considered normative. There's nothing necessarily wrong with this, but in our business engaging in Humpty-Dumptyism must always be avoided.

My last attempt at a response.

I am NOT making up my own definitions.
These are the internationally accepted and defined terms quoted directly from the VIM (International Vocabulary of Metrology – Basic and General Concepts and Associated Terms (VIM). As a matter of fact, there is a new document, VIM3, which provides the VIM definitions along with Informative Annotations, in an attempt to make them clearer. This is a Note found under the definition of Calibration:

"NOTE 2 Calibration should not be confused with adjustment of a measuring system, often mistakenly called “self-calibration”, nor with verification of calibration. "

We Metrology professionals do not take our definitions for Metrology terms from Webster or Wikipedia, or from advertisements.
If you choose to differ from these internationally accepted definitions I would suggest that you take it up with them, and let the folks at BIPM know that they are wrong.
Since I am called to comply with standards such as ISO 17025 and ISO 10012, which refer to the VIM for definitions of terms in their documents, I will continue to use those definitions. They provide clarity where your mashup definitions provide mud.

Again, I point out that accuracy, tolerance, and uncertainty are very often used as synonyms. Just because this happens very often does not make them mean the same thing. Because they don't.

 

[Jim Wynne]

I am NOT making up my own definitions.
These are the internationally accepted and defined terms quoted directly from the VIM (International Vocabulary of Metrology – Basic and General Concepts and Associated Terms (VIM). As a matter of fact, there is a new document, VIM3, which provides the VIM definitions along with Informative Annotations, in an attempt to make them clearer.

Somewhere above I suggested that you are making up your own definitions or subscribing to definitions that someone else has made up. There are people calibrating and verifying all over the world who have never even heard of VIM. That's because they don't need to. Such is not the case for commercial calibration labs operating under 17025 requirements, or captive labs that have adopted the VIM definitions. My point is that the VIM definitions are far from "universal." They're a set of eccentric definitions intended to create understanding amongst an insignificantly small group of professionals. That group does not rule the world of lexicography.

We Metrology professionals do not take our definitions for Metrology terms from Webster or Wikipedia, or from advertisements.
If you choose to differ from these internationally accepted definitions I would suggest that you take it up with them, and let the folks at BIPM know that they are wrong.

They are "internationally accepted" only within a relatively small group.

Since I am called to comply with standards such as ISO 17025 and ISO 10012, which refer to the VIM for definitions of terms in their documents, I will continue to use those definitions. They provide clarity where your mashup definitions provide mud.

So outside of the tiny world of VIM and its adherents, calibration is not a form of verification. That's Humpty-Dumptyism at its finest.

Now I'm done too.

 

[dwperron]

Somewhere above I suggested that you are making up your own definitions or subscribing to definitions that someone else has made up. There are people calibrating and verifying all over the world who have never even heard of VIM. That's because they don't need to. Such is not the case for commercial calibration labs operating under 17025 requirements, or captive labs that have adopted the VIM definitions. My point is that the VIM definitions are far from "universal." They're a set of eccentric definitions intended to create understanding amongst an insignificantly small group of professionals. That group does not rule the world of lexicography.


They are "internationally accepted" only within a relatively small group.

So outside of the tiny world of VIM and its adherents, calibration is not a form of verification. That's Humpty-Dumptyism at its finest.

Now I'm done too.

There are people calibrating and verifying all over the world who have never even heard of VIM.
Are they people you want calibrating your equipment?
Yes, there are also underqualified people purporting to be skilled professionals in many businesses. I don't know for sure, but it seems like you are rooted in the bad old days of "cal labs" - places that slapped stickers on equipment. Look into the industry today and you will see that it is very different from 30 years ago, a much higher skill level and professionalism.

"They're a set of eccentric definitions intended to create understanding amongst an insignificantly small group of professionals."
They are a set of clear, concise definitions that were carefully chosen to promote clear communication amongst measurement professionals.
Sad to see that you feel we are an "insignificantly small group", not sure what you base that conclusion on.

"That group does not rule the world of lexicography."
Correct. We don't have any desire to rule the world of lexicography.
We'll leave that up to professional communicators like yourself.
People who use terms like "tiny world", "Humpty-Dumptyism", "eccentric definitions", "insignificantly small" to refer to people.

 

[lawcch]

Calibrated is when is sent to be adjusted in the calibration shop, verified is when measurements obtained are compared
Against some references (gauges) without the need to send instruments to the calibration shop for verification.
The verification Is an activity to be sure Instruments at still able to give the right measurements.

yes, verification activity should be checked when we want to know the working device has the same accuracy as the reference calibrated device. Whereas the calibration task is refer to sending your working measuring device to metrology centre or metrology lab for external calibration which has higher accuracy measurement at least 5 x to 10 x depending on your own requirements or client needs