The Dutch Metrology Act (2006) states that the Minister of Economic Affairs (EZ) "designates an institution established in the Netherlands, whose task it is to achieve the realization and maintenance of the national measurement standards". These measurement standards serve a public interest and are relevant for, amongst other things, fair trade, science and industry. VSL has been designated by the Minister as the body responsible for carrying out this task.
National measurement standards
Through an agreement VSL has the obligation to maintain the above national measurement standards, as well as other measurement standards to be agreed upon, including the corresponding calibration facilities. The way this is done is described in the Agreement on the maintenance of the national measuring standards, which is closed down annually. The national measurement standards are usually primary, and in some cases secondary, realizations of the quantity corresponding to the SI unit.
Realization of measurement standards takes place in the following nine areas:
- Electricity (DC/LF and HF)
- Ionising radiation
- Mass and related quantities (pressure and viscosity)
- Thermometry (and humidity)
- Time and Frequency
- Flow (low and high pressure gas and liquid flow)
Based on the measurement standards being maintained at VSL, calibrations are performed and certified reference materials are provided. The corresponding certificates are internationally acknowledged under the CIPM (= Comité Internationale des Poids et Mesures) MRA (Mutual Recognition Arrangement). This is an agreement of mutual recognition of national measurement standards and of the validity of calibration and measurement certificates issued by national metrology institutes. On the BIPM Key Comparison Data Base (KCDB) website a complete overview is available of all “Calibration and Measurement Capabilities” an all reference materials of VSL that are recognized under the MRA.
Maintenance of measurement standards
The Agreement on the maintenance of the national measuring standards includes three activities, namely Basic Maintenance, Development and Key Comparisons.
i. to maintain and realize all relevant standards on the present level of accuracy,
ii. to keep equipment used for basic maintenance operational,
iii. to keep in order the RvA accredited management quality system, based on the ISO/IEC standards: ISO/IEC 17025:2005 (calibration), ISO/IEC 17043:2010 (interlaboratory comparisons) and ISO Guide 34 (reference materials),
iv. to maintain contacts within the (inter)national metrological community.
i. to carry out projects involving existing standards leading to, for example, a predefined improvement of the measurement uncertainty, an improvement of the efficiency of the basic maintenance through automising the measurement process, an extension of the calibration range, or the addition of new components to existing reference materials, etc.
ii. to carry out projects based on new methods leading to new measurement standards that fulfill the national need to comply with (inter)national regulations,
iii. to draw up procedures for new measurement standards, in order that the results of the development program is secured within the management quality system.
Key Comparisons are international comparisons aimed at demonstrating the comparability of the Dutch national standards with those of other countries that have signed the CIPM MRA. These Key Comparisons are executed under the flag of both the CIPM and the regional metrology organization EURAMET.