[en] The selection of protective measures and remediation strategies after an accident needs to be based on previously established criteria, to minimize unnecessary stress and the exposures involved in cleanup operations that are not effective in reducing doses to the public. In a first stage, a database describing the countermeasures has been developed including their efficiency on removing contamination from surfaces. However, to assess the effectiveness of cleanup procedures in reducing doses to members of the public, it was necessary to derive specific scenarios in order to simulate the long term behavior of the material in the environment, since the contribution of different surfaces to doses changes with time after contamination. A basic release and exposure scenario was developed to assess the dose reduction due to the mostly used procedures. Exposure scenarios were selected to fit the surroundings of the Brazilian nuclear power plants in Angra dos Reis. Simulations were performed using SIEM, the integrated system for dose assessment after contamination events, developed at IRD. The contamination of urban environments was assessed for Cs-137, as this was found to be the most relevant long term radionuclide to contribute to doses to member of the public. The effects on reducing external exposures were assessed for periods up to 50 years after the contamination. For agricultural areas, the focus was on ingestion doses from contamination with I-131 for periods up to 1 year after contamination. Results will be complemented on the database in order to support multi-criteria decision making processes after accidents. (author)