Guardbanding and the World of ISO Guide 25 Is There Only One Way?

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Guardbanding and the World of ISO Guide 25 Is There Only One Way? (46.93 KB)

Revisions of ISO Guide 25, drafts 5 and 6, currently proposed to be released as ISO 17025, are fairly explicit about claiming an in-tolerance condition:

"When ... parameter(s) are claimed to be within specified tolerances, the measurement value(s), extended by the estimated uncertainty of measurement, shall fall within the appropriate specification limit."

Does this exactly mean that the guardband always equals the UUT specification minus the measurement uncertainty or should a broader interpretation of "extended" be allowed?

From a practical standpoint, guardbanding by the draft proposal can be unnecessarily expensive and counter productive. Can other guardbanding philosophies co-exist in the world of Guide 25 and accreditation?