Radon measurement season in underway
Radon is an odourless and invisible radioactive gas that can be present in indoor air. Prolonged exposure to high levels of radon increases the risk of lung cancer. Radon cannot be detected by human senses, so measuring is the only way to determine indoor radon levels.
Radon measurement takes at least two months
Radon measurement is important in all detached houses and in every apartment on the ground floor of multi-storey buildings.
Radon is usually measured using a radon detector. Detectors can be ordered online from operators approved by the Radiation and Nuclear Safety Authority (STUK). To obtain reliable results, the measurement should be carried out between 1 September and 31 May and must last continuously for at least two months, preferably three.
How often should radon be measured?
The purpose of radon measurement is to determine the average level of radon the occupants of a dwelling are exposed to. A reference level for indoor radon has been set at 300 becquerels per cubic metre (Bq/m³) of air. New homes should be designed and constructed so that radon levels do not exceed 200 Bq/m³.
The Radiation and Nuclear Safety Authority (STUK) recommends repeating indoor radon measurements:
- every 10 years if the previous radon level was higher than 100 Bq/m³
- every 10 years if the radon level after radon mitigation is below 300 Bq/m³
- every 5 years if a radon level of less than 300 Bq/m³ was achieved by radon mitigation and the radon level before the mitigation was higher than 1,000 Bq/m³
- as soon as possible if the building has undergone substantial structural or ventilation-related construction or alteration work, such as:
- replacement of a concrete slab
- replacement of drains
- replacement of the ventilation system.
Radon levels can be reduced using various technical solutions
Radon mitigation can be carried out using, for example, a radon fan (sub-slab suction) or a radon well: A radon fan creates a vacuum under the floor slab and removes radon from beneath it. A radon well extracts air from the soil from a depth of 4–5 metres. The well is installed outside the building.
Other options for reducing radon include timing or improving ventilation and sealing the building’s floor structure.
Read more:
Radon (Radiation and Nuclear Safety Authority, STUK)(external link, opens in a new window)