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Radon is a gas which is naturally in the air, ground and water.
When the radon levels in a building or a workplace are high, this can be harmful for health.
Radon can cause lung cancer.
Radon in residences can come from the ground below and around the building, the building material and the water which is used in the household.
Measuring is the only way to find out if there is radon in a building.
You can receive help for measurement from your municipality.
If the radon is from the building material, you should ensure that the air is changed often in rooms.
Improving the ventilation is often enough.
Another way is to seal walls with "blue concrete" (a type of aerated autoclaved concrete ) with the radon tape.
If the radon is from the ground, you should seal cracks and other leakages in the building's foundation.
If the radon is from household water, adding a radon separator is enough.
By degassing the water strongly with a radon separator, a large part of the radon disappears.