Evaluating the Use of NORM Residues in Building Restoration: A Risk Assessment Approach Using ERICA and NORMALYSA

The increasing use of Naturally Occurring Radioactive Materials (NORM) in masonry restoration raises concerns about radiological risks to both humans and the environment. This study evaluates the radiological exposure from NORM-containing materials, specifically focusing on phosphogypsum, fly ash, and metallurgical slag, commonly used in restoration projects. The assessment is conducted in two steps using two specialized software tools: NORMALYSA and ERICA Tool. NORMALYSA is employed to model the transport of radionuclides from the source to receptors and estimate the effective doses for a representative person, while ERICA Tool assesses radiological doses to biota (ecological receptors). The results for human exposure are compared to those for biota, considering both direct and indirect pathways of exposure, including gamma radiation and radon exhalation. The Concentration Levels (CLs) for radionuclides are calculated using screening values derived from effective dose rates and Derived Consideration Reference Levels (DCRLs), providing a comprehensive risk assessment. This integrated approach, considering the entire ecosystem, supports the development of effective radiation protection models for heritage restoration and ensures compliance with regulatory frameworks.