Radon potential area in Ille-et-Vilaine

Radon is a radioactive gas resulting from the decay of naturally occurring uranium and radium in soil and rocks. By disintegrating, it forms solid descendants, themselves radioactive. These progeny can attach to air aerosols and, once inhaled, settle along the airways causing them to irradiate. The areas most affected correspond to the geological formations naturally richest in uranium. They are located on the large granite massifs (Armorican Massif, Massif Central, Corsica, Vosges, etc.) as well as on certain black sandstones and shales. At the request of the Nuclear Safety Authority, IRSN drew up a map of soil radon potential based on knowledge of the geology of France. This mapping makes it possible to determine the municipalities in which the presence of radon at high concentrations in buildings is most likely. The municipalities are classified into three categories: - Zone 1: areas with low radon potential - Zone 2: areas with low radon potential but where particular geological factors can facilitate the transfer of radon to buildings - Zone 3: areas with significant radon potential The interministerial decree of 27 June 2018, published on 30 June in the Official Journal, defines the radon potential zones of French territory. The map made effective against third parties by the publication of that decree appears on the website of the Institute for Radiation Protection and Nuclear Safety (IRSN). Radon is a radioactive gas resulting from the decay of naturally occurring uranium and radium in soil and rocks. By disintegrating, it forms solid descendants, themselves radioactive. These progeny can attach to air aerosols and, once inhaled, settle along the airways causing them to irradiate. The areas most affected correspond to the geological formations naturally richest in uranium. They are located on the large granite massifs (Armorican Massif, Massif Central, Corsica, Vosges, etc.) as well as on certain black sandstones and shales. At the request of the Nuclear Safety Authority, IRSN drew up a map of soil radon potential based on knowledge of the geology of France. This mapping makes it possible to determine the municipalities in which the presence of radon at high concentrations in buildings is most likely. The municipalities are classified into three categories: - Zone 1: areas with low radon potential - Zone 2: areas with low radon potential but where particular geological factors can facilitate the transfer of radon to buildings - Zone 3: areas with significant radon potential The interministerial decree of 27 June 2018, published on 30 June in the Official Journal, defines the radon potential zones of French territory. The map made effective against third parties by the publication of that decree appears on the website of the Institute for Radiation Protection and Nuclear Safety (IRSN). Radon is a radioactive gas resulting from the decay of naturally occurring uranium and radium in soil and rocks. By disintegrating, it forms solid descendants, themselves radioactive. These progeny can attach to air aerosols and, once inhaled, settle along the airways causing them to irradiate. The areas most affected correspond to the geological formations naturally richest in uranium. They are located on the large granite massifs (Armorican Massif, Massif Central, Corsica, Vosges, etc.) as well as on certain black sandstones and shales. At the request of the Nuclear Safety Authority, IRSN drew up a map of soil radon potential based on knowledge of the geology of France. This mapping makes it possible to determine the municipalities in which the presence of radon at high concentrations in buildings is most likely. The municipalities are classified into three categories: - Zone 1: areas with low radon potential - Zone 2: areas with low radon potential but where particular geological factors can facilitate the transfer of radon to buildings - Zone 3: areas with significant radon potential The interministerial decree of 27 June 2018, published on 30 June in the Official Journal, defines the radon potential zones of French territory. The map made effective against third parties by the publication of that decree appears on the website of the Institute for Radiation Protection and Nuclear Safety (IRSN).