Nouvelle approche de l’évaluation de la dosimétrie extrémités à MELOX

Skin and extremity dosimetry has been set up in order to avoid deterministic effects which might be observed following an important partial exposure. For all that, dose equivalent to skin and extremities have to be measured at the most exposed areas. For that purpose, both the most expose area has to be known and an appropriate dosimeter has to be placed there. It is all the more difficult because the source term is complex and the exposure conditions can vary. It is the case for the extremity dosimetry at MELOX facility. The variety of the working conditions leads to the fact that the most exposed extremity area is not the same for all the operators and can vary due to both workstation features and duration of intervention procedures. Due to these facts, to put a dosimeter at the right position is a matter of concern. The approach presented here consists in characterizing the exposure received by extremities, i.e. in "mapping" the dose equivalents at the level of forearm and hand according to exposure conditions. Following the results obtained, the estimation of the maximum dose equivalent to extremities stemming from a measurement made at a precise point, becomes possible.