Cry for help - FDA calibration requirement for accuracy & precision

normzone

Trusted Information Resource
I'm up against a deadline- I have a question posed re how to meet these requirements for an outside mic working to a +/- .005" tolerance.

It's in this thread

I'm not at my best right now, but the painkillers are wearing off, and I'll probably be smarter soon - I could really use some help.

Thanks -
 
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dgriffith

Quite Involved in Discussions
Like many of the regulations the gov't writes, it is wordy to the point of confusion. They never learned to kiss.
Try http://asq.org/quality-progress/2010/11/measure-for-measure/where-does-it-say-that.html. This article was written by Jay Bucher (RIP), whose was pretty knowledgeable in FDA-related calibration areas. Also, from a different author, this presentation: http://www.ombuenterprises.com/LibraryPDFs/Medical_Device_Calibration_Program.pdf.

Looks like it's just a calibration of a mic. The results should state the accuracy--did the UUT measure the standard within the UUT's tolerance--and did it do it with precision--did several measurements reproduce the same result--and state these results in the calibration report. The requirements for accuracy (allowable error) and precision should be stated in the calibration procedure. Was/were your standards good enough for the calibration.
If it was out of tolerance, what did you do about all the measurements it made on your product since it was last calibrated or known to be good.
I don't see this as any different than Z540-1, .3, 17025, etc..
Accuracy and precision define the requirements for a measurement and its associated equipment.
 
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normzone

Trusted Information Resource
Well, this is the situation as it actually goes down, within the limitations of discrimination.

Dial Calipers used to verify conformance to manufacturing tolerances of +/-.005” must resolve to a degree that supports precision measurement to .001”. Repeated accurate measurements of a given standard traceable to NIST shall not vary by more than a total of .002. Results shall be recorded.

Digital Calipers used to verify conformance to manufacturing tolerances of +/-.005” must resolve to a degree that supports precision measurement to .0005”. Repeated accurate measurements of a given standard traceable to NIST shall not vary by more than a total of .001. Results shall be recorded.

Vernier micrometers used to verify conformance to manufacturing tolerances of +/-.005” must resolve to a degree that supports precision measurement to .0001”. Repeated accurate measurements of a given standard traceable to NIST shall not vary by more than a total of .0002. Results shall be recorded.


Am I anywhere in the neighborhood of the correct interpretation?
 
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