The Radiation and Nuclear Safety Authority (STUK) maintains national metrological standards that enable the reliability of radiation measurements.
Metrological standards are, for example, precise measuring devices (ionization chambers), measurement methods or radiation sources that are used to calibrate other measuring devices. The national metrological activities are the basis for ensuring that the radiation measurements made in Finland in connection with regulatory control are reliable and internationally comparable. STUK also provides calibration and irradiation services for the users and manufacturers of radiation meters.
As a national metrology laboratory, STUK is an expert in radiation metrology (metrology = measurement science). STUK maintains and develops the national metrological standard system and is responsible for the maintenance of the SI system with regard to radiation quantities in Finland.
STUK is a member of the European Association of National Metrology Institutes (EURAMET). STUK is a member of dosimetry section of the International Committee for Weights and Measures’ (CIPM) Consultative Committee for Ionizing Radiation (CCRI) and the European Metrology Network for Radiation Protection (EMN for Radiation Protection). STUK is also a member of the International Atomic Energy Agency's (IAEA) and World Health Organization's (WHO) network of metrology laboratories for ionizing radiation. STUK participates annually in the comparisons organized by the networks.
STUK's status as a national metrology laboratory is based on legislation concerning it. Finland's national metrological activities are maintained by VTT MIKES.