The readings taken at the end of a calibration, after any adjustment, documenting the state in which the instrument is released. When no adjustment is made, as-found and as-left data are identical and many certificates say so. As-left values set the starting point for the next interval, so a drift trend runs from the as-left of one calibration to the as-found of the next.
As left is within 10 percent of tolerance at every point, good to go back to the line.
Also heard as
- as-left data
- as returned
Related terms
As found
Calibration data recorded on an instrument as received, before any adjustment or repair is made.
Adjustment
Changing an instrument so its readings move closer to the correct values, a step separate from calibration.
Calibration certificate
The document reporting a calibration's results, uncertainties, conditions and traceability for one specific item.
Drift
Gradual change in an instrument's readings over time that comes from the instrument itself, not from what it measures.