Routine tritium releases from JET

The JET tritium handling facilities have been designed to minimize tritium release to the environment and to comply with the ALARP principle. However, it is not practicable to reduce such releases completely to zero and JET has therefore applied for official approval to discharge small amounts of tritium in the form of HTO and HT to the atmosphere and tritiated water to a discharge pipeline. The discharge authorizations are based on estimates of routine operational and maintenance emissions. In this paper the basis for these estimates is described and the factors which contribute to uncertainty are discussed. An assessment has been carried out of the resultant radiation does received by hypothetical critical groups. The methodology is described an it is shown that the total dose, including contributions from direct radiation and releases of activation products, is comfortably within the JET design target and well below UK National Radiological Protection Board limits