STUK supervises radiation practices

The Radiation and Nuclear Safety Authority (STUK) supervises the safety of the use of ionising radiation and other radiation practices. The supervision consists of inspections of the radiation facility and other regulatory control methods, such as supervision inqueries, and more. The supervision ensures that the practice is carried out in a safe and acceptable manner and in compliance with the radiation legislation and safety licence conditions.


The Radiation and Nuclear Safety Authority’s (STUK) task is to inspect and observe a practice referred to in the Radiation Act and circumstances that may result in harmful exposure to radiation. The purpose of this is to ensure that the use of radiation sources and other instruments, equipment and supplies affecting radiation safety is appropriate and safe. At the same time, the supervision ensures that the radiation sources and accessories are in good condition and meet the applicable in-service requirements. 

If there are deficiencies in the practice, the inspector may obligate the undertaking to remedy their practice to such a state that it is safe and meets the requirements laid down in the Radiation Act. If the practice fails to accord with the Radiation Act or may cause a obvious health detriment, STUK may order the practice to be discontinued or restricted. In cases that are urgent in terms of safety, the inspector may order the practice to be discontinued or restricted. 

STUK also monitors the transport of radioactive materials. Transport of high-activity sealed sources requires a safety licence, so the supervision is similar to that of other operations requiring a safety licence. The transport of other radioactive materials than high-activity sealed sources is supervised in accordance with the Act on the Transport of Dangerous Goods. The supervision of these materials is often carried out as part of other inspections.

Inspection programme 

STUK draws up an inspection programme concerning the inspections of practices subject to a safety licence. The supervision under the inspection programme ensures that the radiation practice is sufficiently safe in relation to the risks related to it. The inspection programme is also used to supervise that the radiation practice complies with the conditions laid down in the provisions of the Radiation Act and in the safety licences.  

The inspection programme includes regular inspections and inspections based on case-specific considerations announced and not announced in advance. The inspection programme may also include inspections based on surveillance questionnaires and information and data received from the operator which do not include a visit to the location in which the practice is carried out.

Inspections of the radiation facility

STUK directs its supervision on the basis of risks. This means that inspections are targeted at sites where the practice might cause serious or extensive harmful effects from radiation. Inspections are also targeted to sites and operations from which necessary information is difficult to obtain by other means. Correspondingly, less inspections are directed to practices with lower risks. However, the aim is to conduct the inspections in such a way that all practices are inspected comprehensively enough. 

Safety assessments  serve as one of the inputs for assessing the need for an inspection. In some cases, a licencee may be sent a survey to assess the need for an inspection. These surveys can also substitute an inspection. 

Separate commissioning inspections of equipment and practices are carried out if deemed necessary during the processing of the safety licence application. Inspections like these are carried out before the commissioning of the equipment or the commencement of the practice. In some situations, the inspection can be carried out soon after the equipment is put into operation or the commencement of the practice as a so-called first inspection. 

In addition to the situations above, STUK carries out inspections based on case-by-case consideration. This can be done, for example, when an inspection is necessary due to a radiation safety deviation. Inspections are also carried out as repeat inspections at STUK’s discretion. A repeat inspection may be carried out if the previous inspection has revealed shortcomings whose correction must be verified. 

Inspections are also carried out without prior notice in certain situations. An unannounced inspection may be carried out if it is likely that no other method would give a true picture of the practice or if STUK suspects that the practice does not comply with the safety licence. The inspection may also be carried out without prior notice if the operator does not have the required safety licence for the practice. 

Inspections related to granting or changing a safety licence and discontinuing operations are subject to a fee. The fee is in accordance with the decree of public charges issued by the Ministry of Social Affairs and Health. Other on-site inspections carried out by STUK are included in the annual regulatory charges.

Supervision reports 

STUK publishes supervision reports that are based on the data collected through supervision surveys and other supervision activities. The reports contain up-to-date information on the results of the supervision and which sectors the supervision will target next.