Permeability of Different Materials to Radon

000 The permeability of a variety of materials to ^ Rn has been measured in a Radon/Thoron Test Facility (RTTF) of the walk-in type. The measurements were conducted using an automated multi-sensor apparatus consisting of a number of ^Rn passive monitors and meteorological sensors which permit simultaneous permeability studies of up to 12 different materials. Twenty-two different materials were tested. The permeability measured for these c 01 materials ranged from greater than about 1 x 10’ cm s~ to less than -1.0 x 10’9 cn^s’1. Among the several materials investigated, a number of them are suitable as ^Rn barriers. However, for the special application 000 intended here as wall-cover for restricting the flow of Rn from mine walls (which require low permeability to ^^n. as well as great mechanical flexibility and resistance to impact) only two materials are potentially suitable, namely, an epoxy resin, and MIROC™, a polyurethene-based material. Permeability studies are in progress to evaluate other materials for similar applications but different mechanical configurations.