DIN EN ISO 16641:2016-05

Radon isotopes 222, 220 and 219 are radioactive gases produced by decay of radium isotopes 226, 224 and 223. These are each decay products of U-238, Th-232, and U-235. All of these radionuclides are contained in the earth's crust. The decay of radon produces solid elements that are also radioactive, eventually forming stable lead. As a result of its short half-life, radon-220 decays very rapidly in the atmosphere. An activity gradient develops between the walls or the floors and the interior of the room. Depending on the measurement task (building characteristics, building material investigation and so on), this gradient shall be taken into account when choosing the sampling location. This standard covers integrated measurement techniques for radon-220 with passive sampling only. It provides information on measuring the average activity concentration of radon-220 in the air, based on easy-to-use and low-cost passive sampling, and the conditions of use for the measuring devices. The German standard published in 2015 as DIN ISO 16641 (VDE 0493-1-6641) will be adopted without substantive changes as European Standard EN ISO 16641 and then reissued as DIN EN ISO 16641 (VDE 0493-1-6641). The responsible committee is DKE/GUK 967.2 "Aktivitätsmessgeräte für den Strahlenschutz" ("Activity measuring instruments for radiation protection") of the DKE (German Commission for Electrical, Electronic and Information Technologies) at DIN and VDE.