Discontinuing the use of radiation

A safety licence becomes invalid and the license is terminated when the licensee submits a notification on the discontinuation of operations.

The holder of a safety licence must report the discontinuation of the use of radiation in writing. If the licence holder has previously used radiation sources, it must indicate during the safety licence termination process where it has transferred them or how they have been rendered harmless. Sealed sources can be transferred to the manufacturer, importer or Suomen Nukliditekniikka, which manages radioactive waste. After discontinuing the use of unsealed sources, the license holder must present a report on how the waste has been aged and rendered harmless and how the cleanness of the used facilities and equipment has been ensured. When operations involving the use of electrical radiation equipment such as X-ray equipment are discontinued, it must be ensured that the radiation equipment has been appropriately scrapped or rendered unusable. The actions listed above are part of the use of radiation and can be implemented under the safety licence for the use of radiation.

In some cases, however, other actions may be required in conjunction with discontinuing the use of radiation. These actions may include the decontamination of structures, buildings or areas that have been contaminated due to the use of radiation, and the treatment of the radioactive waste generated in the decontamination. Such actions differ significantly from the normal use of radiation. When these actions have not been reviewed during the issuing of the safety licence for the use of radiation, the licence must be supplemented correspondingly, or a separate safety licence must be applied for these actions.  

Some detailed requirements that can be applied to discontinuing the use of radiation are provided in different ST Guides. Guide ST 5.1, for example, presents procedures for decommissioning sealed sources, Guide ST 6.2 presents procedures for the treatment of waste generated by unsealed sources, and Guide ST 1.5 presents procedures for releasing radioactive materials for reuse, recycling and disposal as waste without additional requirements.