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Changes in the use of radiation

Changes in the use of radiation

If there are changes in the use of radiation by a licensee, they must be reported to the Radiation and Nuclear Safety Authority in writing.

STUK must be notified within two weeks of the time when:

  • a radiation source is acquired
  • a radiation source is transferred
  • a new radiation safety officer is appointed
  • any essential change takes place in the radiation user’s organization
  • the use of radiation is discontinued in whole or in part.

In certain cases, a notification of the change must be submitted in advance, such as when planning the commissioning of new X-ray or radiotherapy equipment in health care or before new health care facilities are commissioned. Furthermore, a notification must be submitted in advance when a high-activity source of radiation (HASS source) is commissioned.

You can read more about the safety licence and its changes on the Safety Licence page.

The written notification to STUK is submitted using a form, which is available on the Forms page, or with a free-form application; however, the notification must contain, at a minimum, the information covered by the corresponding form.

Osion etusivun tekstinosto Safety licence

Safety licence

A safety licence is required for the use of radiation. Use of radiation includes all practices concerning radiation sources, such as trade in radiation sources and the manufacture, possession, servicing, repairs, import and export of radiation sources. Radiation sources include X-ray equipment, radioactive substances or devices that contain them.

Osion etusivun tekstinosto Discontinuing the use of radiation

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.

Osion etusivun tekstinosto Forms


When filling in an application form, it is useful to refer to the ST Guides concerning the activity in question.