The standard that does the daily bench work of calibrating and checking instruments, such as a bench multifunction calibrator, a set of working weights or a deadweight tester on the pressure bench. It is calibrated against the lab's reference standard at regular intervals and takes the wear and handling the reference is spared. Its uncertainty is somewhat larger than the reference's because it sits one link further down the chain.
Working standard weights came back 2 mg light, check every scale we've done since the last comparison.
Also heard as
- bench standard
- working set
Related terms
Reference standard
A lab's highest-level standard for a quantity, used only to calibrate other standards and never for routine work.
Check standard
A stable item measured regularly to confirm a measurement process still behaves as it did when characterized.
Calibration hierarchy
The ranked levels of standards, from primary realizations down to working instruments, through which values flow.
Traceability chain
The documented sequence of calibrations linking a working instrument back to national or SI-level standards.