Repair (minor)

Minor repair is the process of quickly and economically returning an unserviceable item to serviceable condition by doing simple work using parts that are in stock in the calibration lab.

Reported value

One or more numerical results of a calibration process, with the associated measurement uncertainty, as recorded on a calibration report or certificate.

Scope of accreditation

For an accredited calibration or testing laboratory, the scope is a documented list of calibration or testing fields, parameters, specific measurements, or calibrations and their best measurement, uncertainty.


Self-calibration is a process performed by a user for the purpose of making an IM&TE instrument or system ready for use.


In metrology, a specification is a documented statement of the expected performance capabilities of a large group of substantially identical measuring instruments, given in terms of the relevant parameters and including the accuracy or uncertainty

Standard (document)

A standard (industry, national, government, or international standard; a norme) is a document that describes the processes and methods that must be performed in order to achieve a specific technical or management objective, or the methods for evaluation of any of these.

Standard (measurement)

A standard (measurement standard, laboratory standard, calibration standard, reference standard; an étalon) is a system, instrument, artifact, device, or material that is used as a defined basis for making quantitative measurements. 

Standard reference material

A standard reference material (SRM) as defined by NIST “is a material or artifact that has had one or more of its property values certified by a technically valid procedure, and is accompanied by, or traceable to, a certificate or other documentation which is issued by NIST

Standard uncertainty

The uncertainty of the result of a measurement, expressed as a standard deviation. (GUM, 2.3.1)

System owner

The person responsible for the availability, and maintenance of a computerised system and for the security of the data residing on that system.

Systematic error

A systematic error is the mean of a large number of measurements of the same value minus the (probable) true value of the measured parameter

Test accuracy ratio (TAR)

In a calibration procedure, the test accuracy ratio (TAR) is the ratio of the accuracy tolerance of the unit under calibration to the accuracy tolerance of the calibration standard used.

Test uncertainty ratio (TUR)

In a calibration procedure, the test uncertainty ratio (TUR) is the ratio of the accuracy tolerance of the unit under calibration to the uncertainty of the calibration standard used.


A tolerance is a design feature that defines limits within which a quality characteristic is supposed to be on individual parts; it represents the maximum allowable deviation from a specified value.

Traceable, traceability

Traceability is a property of the result of a measurement, providing the ability to relate the measurement result to stated references, through an unbroken chain of comparisons each having stated uncertainties.

Transfer measurement

A transfer measurement is a type of method that enables making a measurement to a higher level of resolution than normally possible with the available equipment.

Transfer standard

A transfer standard is a measurement standard used as an intermediate device when comparing two other standards.

Type A evaluation (of uncertainty)

Type A evaluation of measurement uncertainty is the statistical analysis of actual measurement results to produce uncertainty values

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