Periodic Metrological Control
Periodic inspection of measuring instruments not subject to the legal metrological control system.
Legalization
Verification, confirmation, and certification by a legalization certificate that a measuring instrument meets technical and metrological requirements, and that its measurement errors do not exceed the permissible maximum values. The legalization certificate does not specify the magnitude of the errors.
Calibration
Determination of the relationship between the values of the measured quantity indicated by the measuring instrument and the corresponding values of physical quantities realized by a standard (does not include adjustment of the measuring instrument).
Calibration of gas mixture component content meters involves reading the instrument’s indications while supplying a reference gas with a precisely known component concentration and determining the instrument’s measurement error and uncertainty.
Calibration allows for assessing and documenting the measurement capability of instruments.
Adjustment (colloquially referred to as calibration)
An activity aimed at bringing the measuring instrument to a functional state corresponding to its intended use. It involves adjusting the measurement system so that the instrument’s readings match the values of the given reference gas.
Measurement Uncertainty
The risk of obtaining an incorrect result in measurement; it characterizes the spread of values that can reasonably be attributed to the measured quantity. It is the sum of the uncertainties contributed by standards and measuring instruments.
Preliminary Inspection
A set of procedures carried out in the laboratory to check the functionality of a measuring instrument submitted for calibration, in aspects relevant to performing measurements specified by the client’s inspection order.