Radon gas is naturally found in soil and rocks. Therefore, the ground air almost always contains radon. The air pressure is usually lower indoors than outdoors and radon can therefore be sucked into houses from the ground. If large amounts of ground air leak into the house, there is always a risk of high radon levels indoors.The radon situation in the municipality has been surveyed and reported on a radon risk map showing areas with low, normal and high risk for ground radon. However, it has been found that the classification of the soil does not have much significance for how many houses with elevated radon levels are found. The most important factor is whether there are any leaks in the floor plate or floor that cause ground air to enter the houses.If you have any questions about the data set, please contact miljoochhalsoskydd@umea.se