Calculation of environmental and health effects The CEA conducts research on the effect of nuclear facilities and the radioactive waste industry on health. It has build a center of excellence, which aims at assessing the potential effects of nuclear facilities - whether those of the CEA or other operators - on the environment and human health. Scope   waste discharge permit application reviews, hazard studies, "waste" outlet creation, contaminated site sanitation assistance. Expertise   frequent environmental and health impact studies, computational tool maintenance and development, involvement in CEA crisis exercises, database compilation: more than 200 different radionuclides and all types of basic nuclear facilities (BNF): reactors, laboratories, plants, etc. Impact studies   These require: knowledge of local meteorological conditions, calculation of the atmospheric distribution of radionuclides in the air and their deposition on the ground, estimation of total exposure for sensitive populations (adults, children and babies) at target points, exposure distribution assessment at a given point, depending on the possible exposure pathways (irradiation, inhalation and ingestion).     In facilities: from inventory to source term.   In the atmosphere: from chimney to points of impact.   In the food chain: from point of impact to human beings.     Examples of impact calculation representation methods   Atmospheric transfer coefficients, characteristic of radionuclide transport from the outlet (e.g. chimney) to the points of impact located at different distances from the source. Angular deviations given in relation to north.     Tritium source term exposure depending on location and age group.     The different exposure pathways for an adult in a given location.