Monitoring radioactivity in the environment is carried out by collecting data through measuring and calculating emissions, immissions and the resulting human exposure to radiation.
Measurements to monitor environmental radioactivity have been carried out since the 1950s. At that time, the aim was to collect data on the radioactive fallout from nuclear weapons tests conducted above ground.
When the Treaty establishing the European Atomic Energy Community (EURATOM Treaty) was signed in 1957 with the aim of developing the peaceful use of nuclear energy, all member states committed to monitoring radioactivity in the air, water and soil and to reporting on the results.
To do so, Germany had to develop a network of official measuring stations. The monitoring tasks were divided between the Federation and the Länder and laid down in an executive agreement in 1961. Since then, federal authorities monitor radioactive substances in the air, atmospheric precipitation, federal waterways and the North and Baltic Seas, while authorities of the Länder monitor all other media using their own measuring stations. The system of coordinating offices was established around the same time; these offices coordinate, advise and carry out quality assurance measures.
Monitoring of radioactive emissions and the resulting inputs into the environment was also introduced based on the Atomic Energy Act (AtG) when the large-scale use of nuclear energy started in the early 1960s. The Guideline concerning Emission and Immission Monitoring of Nuclear Installations (REI) was drafted on the basis of various previous versions and sets out requirements for facility-related monitoring.
When the accident at the Chernobyl nuclear power plant led to Europe-wide environmental contamination in 1986, large-scale monitoring of environmental radioactivity was re-introduced; it had lost importance with the end of above-ground nuclear weapons tests. The Precautionary Radiation Protection Act (StrVG) regulated this new monitoring activity, which was expanded with the aid of information technology, later establishing the Integrated Measuring and Information System (IMIS).