Main Parameters Influencing the Level of Labile Contamination and the Removal Factor

Abstract

Several nuclear facilities are currently being decommissioned in France, on CEA and EDF sites. The decommissioning process as a whole, with cutting operations and nuclear waste management presents workers with significant risks of exposure. The aim of this study was therefore to improve risk assessments of internal exposure in operations where the main uncertainties are the removal factor and the airborne release factor. A new method is presented to assess the risk of internal exposure and optimize the choice of personal protective equipment to use during nuclear dismantling operations. The main forces and parameters influencing the level of labile contamination and particle resuspension were identified from a literature review and feedback. A manageable set of parameters was then obtained based on literature data and on-site information. The effects of the drying temperature, relative humidity, roughness of the contaminated surface, and wiping pressure were thus investigated on labile contamination and removal factor measurements. Successive wipings with cotton pads were performed on surfaces contaminated with simulated contaminants to estimate the influence of the different parameters. Results highlight the importance of surface roughness over the other considered parameters.