What is radon?

Natural, radioactive gas

Radon is a naturally occurring, radioactive gas that is produced by the decay of uranium in the ground. It can penetrate through leaks in the foundation adjacent to the ground and accumulate in the building. The so-called "chimney effect" is the driving force behind the transport of radon into the building: warm room air rises and causes a barely perceptible negative pressure on the lowest floors. This creates a suction effect. Basement rooms are particularly affected by direct contact with the floor. However, the gas also finds ways to reach the upper, inhabited floors within a building. This suction effect can be further intensified by exhaust fans or fireplaces.

Health risk

Excessive indoor radon concentrations pose a health risk as they increase the risk of lung cancer. In Switzerland, the average annual radon concentration is set at 300 becquerels per cubic meter of air (Bq/m³). It applies to rooms in which people regularly spend several hours a day. In addition to this reference value, a threshold value of 1000 Bq/m applies at workplaces exposed to radon³ for the radon gas concentration averaged over one year.

Radon measurement

Radon is invisible and odorless, which is why a radon hazard can only be detected with a measurement. Radon measurement is simple: the easiest way to measure the radon concentration in indoor air is with a so-called passive radon dosimeter. These are small plastic containers that require no electricity and emit neither light nor noise, but are simply left on for a certain period of time.

Recognized radon measurement / long-term measurement

This measurement lasts, if possible, one year, but at least 90 days during the heating period from October to March. Recognized radon measurements are carried out using dosimeters and according to prescribed measurement protocols.

Orienting short-term measurement

This measurement is useful if it is not possible to wait for a 90-day, recognized radon measurement during the heating period. For example, before a building renovation or a real estate transaction, it is an important measure to assess the risk of radon contamination. Dosimeters are also used for this measurement, but these are usually only exposed for 2 - 4 weeks.

Time-resolved radon measurement

Special radon measuring devices are used for these measurements. These devices record the radon concentration in the form of a measurement curve and are typically placed at strategic locations in the building, for example to know the radon exposure at certain times. For more information or a quote, please contact us.