Radiation monitoring
National Radiation Monitoring Sub-Programme
Pursuant to the Environmental Monitoring Act and the Regulation of the Minister of the Environment, "Requirements and Procedure for Compliance with the National Environmental Monitoring Programme and Sub-Programmes", the Environmental Board is the responsible executor of the national radiation monitoring sub-programme.
According to the Regulation of the Minister of the Environment "Statutes of the Environmental Board", the task of the Climate and Radiation Department of the Environmental Board in the field of radiation is to:
- Organise monitoring of environmental radioactivity and conduct analysis of monitoring results
- Carry out laboratory analysis of the radioactivity of substances and studies of natural exposure
- Assess resident exposure
- Ensure the operation of the early warning system against radiation risk.
International requirements
The Republic of Estonia is obliged to comply with the requirements of Articles 35 and 36 of the Treaty establishing the European Atomic Energy Community (EURATOM).
Article 35 provides that a Member State must provide the necessary means for continuous monitoring of the level of radioactivity in air, water and soil and comply with the basic standards.
Under Article 36, monitoring data must be communicated periodically to the European Commission in a predetermined format in order for the Commission to be aware of the level of radioactivity affecting the population. A common methodology has been implemented in environmental radiation monitoring, as described in Commission Recommendation 2000/473/Euratom of 8 June 2000.
The European Commission carries out audits in EU Member States to monitor national radiation monitoring arrangements both in normal and emergency conditions.
of the Environmental Board. Photo: Uko Rand
Reports on radiation monitoring and international audits
Early warning of radiation hazards
In case of serious nuclear and radiation accidents, radioactive pollution entering the atmosphere may also exceed national borders.
Information on the danger and the peculiarities of the spread of pollution provides an opportunity to make operational decisions to protect the population.
The Estonian early warning of radiation hazard monitoring network consists of two types of measuring devices:
1. AUTOMATIC RADIATION MONITORING STATIONS (FOR MONITORING DOSE RADIATION) (15);
2. FILTER STATIONS (FOR MONITORING AIR-CARRYING PARTICLES) (3).
Automatic monitoring stations
station. Photo: Teet Koitjärv
The monitoring network warning early of radiation risk consists of 15 automatic radiation monitoring stations that measure the total gamma radiation level (nSv/h) in the air in real time across Estonia.
Gamma radiation is measured by the system mainly by a NaI(Tl) crystal-based detector that measures the total gamma-ray dose rate, tests radionuclides, and assesses the dose radiation caused by various radionuclides.
In addition to the crystal, the device also includes a Geiger-Müller detector, which is more capable of recording higher dose speeds.
A component caused by artificial radionuclides is of particular interest. This is compared to a predetermined alarm level. In case of a qualifying radiation level, the stations will also forward a notice to the Environmental Board.
Air filter stations
Aerology Station. Photo: Uko Rand
Early warning also includes monitoring of the radioactivity of atmospheric particles and aerosols, which is carried out at three monitoring stations: in Harku, Narva-Jõesuu and Tõravere.
The devices use glass microfiber filters, which are changed once a week and analysed in the laboratory of the Climate and Radiation Department of the Environmental Board. Laboratory analysis of filters allows to detect very low concentrations of activity of radionuclides in the air (μBq/m3).
The most important indicator of radioactive contamination of the atmosphere is the anthropogenic radioisotope Cesium-137 (Cs-137), which is always found in the air to a small extent. There is always a natural radioisotope, Berylleum-7 (Be-7) in the atmosphere.
Last updated: 02.12.2022
