Bituminous membrane design for radon protection

Abstract Radon gas is considered a significant hazard to human health due to its radioactive character and its relationship with lung cancer. In response, national and international organizations have developed regulations to reduce radon exposure in indoor environments. In this study, novel nanocomposites based on styrene–butadiene–styrene (SBS) copolymers and bitumen were developed by incorporating two‐dimensional (2D) nanomaterials to create effective physical barriers against radon gas. The resulting materials were evaluated for potential application in the building sector to mitigate radon permeation. The best‐performing formulations achieved radon diffusion coefficients on the order of 10 −12 m 2 /s, below the limit established by European Directive 2013/59/EURATOM for radon barrier materials. Mechanical and physical characterization confirmed that the incorporation of nanofillers did not significantly alter the properties of the SBS–bitumen matrix. Overall, the developed nanocomposites exhibit promising performance as functional barrier materials for reducing indoor radon exposure and improving building health safety.