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.
Principles
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.
Results of supervision
STUK publishes the results of the supervision from the data collected in the supervision questionnaires and other supervision activities. Simultaneously, up-to-date information on radiation activities is maintained. The information obtained is used to decide on the future direction of supervision.
Licensees using devices that generate radiation electrically
STUK focuses the supervision of X-ray device licensees to those whose activities have not been inspected for a long time or have never been inspected. One of the main focus points this year is to inspect log scanning X-ray device licensees, for which the use of such devices has increased in Finland. As a risk-based monitoring, inspections to industrial radiography licensees will be conducted. These inspections will be performed to full operations as well as to individual sites of operation.
Licensees using sealed sources
The supervision of sealed source activities focuses on licensees that have not been inspected for a long time, and in particular to licensees who have a significant number of sealed sources, or the sealed sources are reaching the age of 40 years. The aim is to ensure that the radiation use of such licensees complies with the requirements of the current Radiation Act and the licensees are prepared to the procedure of decommissioning sealed sources.
Licensees using open sources
STUK supervises the use of open sources at the universities. Furthermore, licensees having other radiation sources in addition to open sources will be supervised.
Licensees with maintenance services of radiation sources and devices
The quality control of radiation sources and devices include regular checks and maintenance of the device. Professional maintenance services help to ensure, that the radiation device can be used safely. A large proportion of other radiation users are thus affected by the activities of operators providing maintenance services of radiation sources and devices. At the end of 2024 a survey regarding maintenance services was sent to licensees providing such services, and the results have been utilized in selecting the licensees to be inspected. Supervision of maintenance service operators by STUK is also used to assess if clarifications regarding the maintenance services are needed in the current Radiation Act.
Operators transporting sealed sources
Licensees transporting high-activity sealed sources are inspected. The results of a survey on transportation of radiation sources are used in the selection of licensees to be inspected. The transportation survey was sent by STUK in January 2025 to operators who might send, transport or receive radioactive materials.
Radiotherapy, including radionuclide treatments, results in significant planned radiation exposure for the patient. Because the doses used in these treatments are very high, there are inevitably risks involved, which are managed by foresight and preparation. In external radiotherapy in particular, accurate dosimetry and precise targeting of the dose is essential to ensure the correct radiation dose for the patient. In addition to external radiation exposure, nuclear medicine also involves the possibility of internal exposure and the risk of contamination from open sources.
In X-ray imaging, the risks are lower and the exposure pathway is more constant. On the other hand, there are many operators and their level of competence in radiation safety varies widely. The operators range from large hospitals to veterinary and dental clinics. There are also many types of activities within a hospital, from the X-ray department to imaging in, for example, surgical wards.
Based on the evaluation of activities, it has been decided to set inspection intervals for external radiotherapy operators, a minimum inspection interval for isotope medicine operators, and to monitor X-ray imaging operators mainly on the basis of random checks, in addition to which other means of supervision activities will be used to maintain a comprehensive understanding of activities.
The target interval for periodic inspections of radiotherapy activities is three years. These inspections provide a comprehensive overview of the overall operation and ensure that it meets the requirements. In addition, the target interval for regular periodic inspections of treatment equipment used in radiotherapy is two years, and three years for imaging devices used for planning the radiotherapy. Treatment device inspection focuses, among other things, on ensuring the input data for dose planning, while, with planning imaging devices, the focus is on the factors related to targeting. New radiotherapy devices are typically subjected to an initial inspection before being used for patient treatment. This is primarily to ensure that the hospital has carried out its own acceptance inspection measurements and determined patient doses and to ensure that they are accurate. In addition, radiotherapy planning imaging equipment is inspected approximately 6–12 months after it has been put into service. STUK inspects some of the activities of practically every radiotherapy clinic every year.
A nuclear medicine site is always inspected at least one year after a significant change in opeartions or the launch of a new site. In particular, conducting of contamination measurements is inspected unannounced at sites as part of other supervision. Each nuclear medicine site is inspected at least every five years. In addition to site inspections, other means of supervision are also actively used.
The following themes, among others, are addressed and applied during the planning periodical inspections and other supervision:
- Dose planning and verification of radionuclide treatments
- Continuous improvement of safety culture
- Training for radiation safety deviations
- Exposure from the potential secretion contamination of patients discharged from radionuclide treatments
- Handling of deceased persons irradiated due to radionuclide treatment
- Public exposure from the iodine treatment of cats
In the supervision of X-ray activities in the health care, dental and veterinary sectors, the inspected sites are selected to maximise the impact in terms of radiation safety and compliance with the law. In addition, a new operator starting a business, other than a conventional dental imaging business, is subject to an inspection at its site within one or two years of its establishment. In connection with the introduction of new imaging equipment, computed tomography equipment and fixed fluoroscopic equipment used in interventional radiology are inspected a few months after the equipment has been introduced, if it has been installed in new facilities or if significant changes have been made to the radiation protection of the facilities.
In addition to aforementioned, the following themes, among others, are addressed during inspections and other supervision:
- Safety culture and training in radiation safety at large public imaging units.
- Operators on the private sector with multiple sites where radiation is used
- Use of radiation at an interventional radiology unit
- A questionnaire is being developed and piloted in the field of dental and veterinary radiology supervision, which could be used to maintain an overall picture of the field in the future.
- STUK's serial publication (julkari.fi) (in Finnish)