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Radon is a radioactive noble gas exhaled from the soil that can reach high concentrations in enclosed spaces. As elevated concentrations cause serious health problems, legislation has been put in place in many countries to regulate the limit concentration and even establish mitigation techniques. One of the most effective techniques for new buildings is the installation of radon barriers. The most important parameter determining whether the barrier is adequate to protect against radon is the diffusion coefficient, whose measurement methodology is standardized in ISO/TS 11665–13:2017. This work applies a previously tested modification of this standard to calculate the radon diffusion coefficient of different materials used as single or multilayer form barriers. Given that there are wasted laminated materials, composed of polymeric materials and aluminium, which are difficult to recycle, a preliminary study of the possible effectiveness of these materials as radon barriers will be carried out using these materials separately or in combination. The materials to be tested are 10-μm sheets of polyethene (PE) and 15-μm sheets of aluminium (Al), testing in each case one, two and three layers of each material. In addition, combinations of the two materials, i.e., PE-Al-PE and PE-Al-PE-Al-PE, are also studied. The diffusion coefficients obtained vary around 2·10−12 m2/s for PE and around 1·10−13 m2/s in the case of Al. The combination of both materials improved results obtained for single-materials barriers giving a diffusion coefficient between 10−13 and 10−14 m2/s. Radon reductions achieved range from 70 to 87.5% for PE to more than 98% for Al and the materials combinations. The excellent radon shielding capacity of aluminium is observed, which grows with increasing material thickness. Furthermore, it can be stated that the use of multilayer materials of different nature is very effective in reducing the radon concentration reaching an enclosed space and the use of aluminium in some of the layers is essential to achieve a more significant shielding effect. • Multilayered materials of diverse nature reduce radon concentration effectively. • Aluminium is essential to achieve a more significant barrier effect. • The PE-Al-PE-Al-PE combination is the best solution for radon barrier. • For combined materials, radon adsorbed is lower than for those materials individually. • Laminated materials wastes could be used as radon barriers. [ABSTRACT FROM AUTHOR]

Due to the health risks posed by high radon concentrations, many regulations impose concentration restrictions and set out several techniques to prevent radon entry into enclosed spaces. One of the most effective technique to protect new buildings from radon entry is to install a radon barrier over the entire surface of the ground beneath the foundation. Whether a barrier is suitable for protection is determined by the diffusion coefficient, the methodology which is standardised in ISO/TS 11665-13:2017. These barriers are typically made of polymeric or bitumen materials, which have diffusion coefficients between 10−11 and 10−13 m2/s. By applying a modification to the ISO standard that allows shorter test times, the diffusion coefficients of a commercial membrane (6.21 ± 0.75 ·10−13), polyethene (1.14 ± 0.14 ·10−12), polypropylene (4.35 ± 0.53 ·10−14), polyvinyl chloride (3.55 ± 0.43 ·10−14), polystyrene (4.96 ± 0.60 ·10−13) and polymethyl methacrylate (4.07 ± 0.49 ·10−13) have been measured, the latter two material values not being published so far. The results validate the developed methodology since the diffusion coefficients provided are comparable with those of the literature. In all cases, a concentration reduction of 99% is obtained. A relationship is observed between the amount of radon adsorbed by the material and its thickness and chemical composition. • Radon diffusion coefficient based on ISO/TS 11665-13:2017 norm is estimated. • Slight modification of the ISO norm allows the reduction of the measurement time. • Diffusion coefficients of different polymeric barrier materials are calculated. • A reduction of radon concentration above 99% is achieved. • The chemical composition of the materials influences their ability to adsorb radon. [ABSTRACT FROM AUTHOR]