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STUK supervises

Responding to abnormal incidents

Responding to abnormal incidents

The response to abnormal incidents must be quick.

Abnormal incident

An abnormal incident in the use of radiation deviates from normal radiation use, resulting in a substantial safety hazard at a location where radiation is used or in its vicinity. An abnormal incident may also consist of an exceptional observation or fact that is of substantial significance to the radiation safety of workers, the environment or patients. Furthermore, abnormal incidents include situations where a radiation source is lost or stolen or where the holder of the safety licence otherwise loses possession of the source. The internal procedures of the location are primarily followed in abnormal incidents.

The correct procedure

1. Immediate measures

Limiting radiation exposure as much as possible

  • Identify and limit the area that poses a radiation hazard.
  • Prevent unauthorized access to the area.
  • Wear respirators if there may be radioactive substances in the breathing air and the area cannot be evacuated.

Preventing the spread of the contamination

  • Prevent access to the contaminated area.
  • Do not handle contaminated items.
  • Wear protective gloves and clothing.

Reporting the incident to the radiation safety officer

2. Documenting the description of events

Document the following without delay, before details are forgotten:

  • sequence of events, the measures taken and the times
  • name and contact information of everyone exposed or involved in the incident
  • specific information on the exposure (periods of stay at different distances from the source, use of respirators, etc.)

3. Reporting the incident to the other parties, as necessary

  • Radiation and Nuclear Safety Authority
  • Valvira
  • Police

4. Measures for determining the magnitude of radiation exposure

5. High-exposure incidents

  • Assess the physical condition of the exposed persons.
  • Perform a chromosomal analysis.

6. Incidents involving a patient

  • Brief the patient and the attending physician.

More instructions on the procedure in abnormal incidents are presented in Guide ST 1.6. If necessary, the Radiation and Nuclear Safety Authority participates in the inspection of an abnormal incident, for example by surveying the incident location.


Use of radiation in health care
Telephone 09 759 88 246
Industrial use of radiation
Telephone 09 759 88 246
Dental X-ray examinations
Telephone 09 759 88 520 or 09 759 88 300
Veterinary X-ray examinations
Telephone 09 759 88 246