Remote measuring system for monitoring the iodine immission in the vicinity of nuclear power plants

Radioactive substances may be released into the atmosphere during major accidents at nuclear facilities. Since the emission rate and composition of the mixture of emitted nuclides is generally not known, appropriate measurements must be made in the vicinity of the plant. The radiation exposure in the possibly critical exposure pathways, i.e. the whole-body dose due to γ-submersion and the thyroid dose due to incorporation of radioiodine, should be determined immediately at various locations in the environment. In general, existing systems only provide telemetric monitoring of the γ-dose rate during an accident. A suitable iodine measuring instrument and a data transmission and processing system have therefore been developed at the Nuclear Research Centre Julich for use during accidents