Radon emanation rates of common partition materials in Hong Kong

Purpose - To determine the radon emanation rates of common partition materials in Hong Kong. Design/methodology/approach - An initial slope of radon gas growth against time and a mass balance analysis can be used to quantify the magnitude of these rates from different types of partition materials. In particular, the radon-222 emanations from boards of calcium silicate, gypsum and lightweight concrete were measured experimentally in a small impervious radon chamber. Findings - The radon-222 emanations from boards of calcium silicate, gypsum and lightweight concrete were measured experimentally in a small impervious radon chamber, and expressed as becquerels per square meter per hour of air (Bq m-2 hr-1). The rates found were 2.43, 0.22 and 0.46 Bq m-2 hr(1 respectively. Comparing with the emanation rate and the quantities of radon emitting construction materials in Hong Kong, these three partition materials have a low radon emitting level. Research limitations/implications - The model parameters used in the study were not exhaustive and were determined from samples of materials used in Hong Kong. Practical implications - A useful source of reference for determining the radon emanation rates of common partition materials used in building developments. The results can be used to identify the exposure risk of radon in buildings. Originality/value - This paper proposes a mathematical model of radon emanation rates of common partition materials. The model offers practical helps to professionals planning, designing and managing the selection of building materials in buildings.