Evaluation of the radiative risks of HERMES astronauts

After a short background on HERMES studies related to the evaluation of the astronauts' radiation exposure, a chronology of these studies is presented. Each evaluation is described in four steps. Each step is analysed and the hypothesis and results are compared with the US and Soviet experiences. The first step concerns the environment. The human limits for ionizing radiation exposure is discussed in the second step. The processes of evaluation of the received doses during HERMES missions is presented in the third step. In the last step, the results are compared with the results of flight measurements.<>