A conspicuous red label hung on equipment that has failed calibration, is damaged or is overdue, meaning it must not be used until it is repaired, recalibrated or scrapped. As a verb, red-tagging an instrument pulls it from service and usually sends it to the quarantine cage. The tag is a visual control so nobody grabs a bad gauge from a bench drawer without seeing its status.
Red tag that caliper, the jaws are worn and it read 0.05 over on the 25 mm block.
Also heard as
- red-tagged
- reject tag
- do not use tag
Related terms
OOT
Out of tolerance, an as-found calibration result outside the instrument's allowed limits.
Out of cal
Past its calibration due date, so the instrument is not approved for use regardless of how well it performs.
Cal sticker
The label on a calibrated instrument showing who calibrated it, when, and when the next calibration is due.
Limited cal
A calibration covering only some ranges or functions of an instrument, flagged with a special sticker.