Nearly 400,000 homes in Sweden have elevated levels of radon in indoors, i.e. over 200 Bq/m3 (*). To find and fix all residential buildings, the radon measurements are needed in almost all houses and apartments with ground contact or if they are built with blue concrete.
You should measure the radon levels:
- When buying a house.
- In new construction, renovation and extension of houses.
- If you know or suspect that the house is in an area with high levels of radon or could be built with blue concrete.
- When changing the ventilation or heating systems.
- The most common method to measure radon in indoor air is to use small measuring cans, called trace film cans.
Such a measurement is easy to do. Measurement in single or two-story houses costs between 200 and 500 SEK, i.e. 22 EUR and 55 EUR.
The measurement shall be made in the part of the year when you need to heat the house (heating season), that is normally from October to April. The measurement period shall be at least two months, preferably three, giving an annual average. You can live as normally during this time of such a long-term measurement.
But then what? How long results are valid? Circumstances may change (environment, ventilation, new materials for further redevelopment, etc.), these changes can again affect / change radon levels.
* Becquerel is the unit of measurement for radioactive decay. 1 becquerel = 1 disintegration per second.
Source from Strålsäkerhetsmyndigheten, www.radonguiden.se