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Calibration · Glossary

What are As Found and As Left?

before and after adjustmentCalibration

As found and as left are the calibration readings taken before any adjustment (as found) and after adjustment (as left).

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As Found and As Left Explained

As found data shows how the instrument performed in service, which is needed for safety records, interval decisions and quality investigations. As left data proves it was returned within tolerance.

Never adjust before recording as found values.

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Calculators for As Found and As Left

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Frequently Asked Questions

What are As Found and As Left?

As found and as left are the calibration readings taken before any adjustment (as found) and after adjustment (as left).

What if as found is out of tolerance?

Record it, adjust, and assess whether products or safety were affected since the last calibration.

If as found passes, should I adjust?

Many procedures leave it, or adjust only if near the limit, to preserve drift history.

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Related Terms

Calibration termCalibrationCalibration is the comparison of an instrument reading with a known reference standard, recording the…Calibration termCalibration IntervalA calibration interval is the time between scheduled calibrations, set so the instrument is likely to…Calibration termFive Point CalibrationA five point calibration checks an instrument at 0, 25, 50, 75 and 100 % of range, usually rising and falling.

More Calibration Terms

Calibration termDriftDrift is a slow change in an instrument reading over time when the input stays the same.Calibration termCalibration CurveA calibration curve is a fitted relationship between instrument reading and true value, used to correct…Calibration termCalibration CorrectionA calibration correction is the value added to an instrument reading to obtain the corrected value; it is…Calibration termCalibration CertificateA calibration certificate is a formal document reporting calibration results, the reference used,…Calibration termISO/IEC 17025ISO/IEC 17025 is the international standard for the competence of testing and calibration laboratories.Calibration termAccuracyAccuracy is how close a measurement is to the true value; in specifications it is the maximum expected error.

All calibration terms · Full glossary A to Z

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