During this period, the windows of buildings tend to remain closed more tightly, limiting the exchange of air and thus increasing the radon concentration inside them, and the heat generated by the heating system generates the so-called chimney effect, which contributes greatly to the transfer of radon from the subsoil into living rooms.

The beginning of autumn is therefore the ideal time to start the measurement, which is only legally valid if the duration of the measurement includes a minimum period of 90 days between October and March. On the subject of legislation, it should be borne in mind that the new Swiss radon legislation, which came into force in 2018 and is aligned with the European directives, has lowered the acceptable concentration threshold (from 1,000 Bq/m3 to 300 Bq/m3), making it even more urgent to monitor dwellings and intervene where necessary.

But what exactly is radon and where does it come from? What are its effects and major health risks? We talked about this with Luca Pampuri, head of the Radon Competence Centre (CCR) at SUPSI (Department of environment constructions and design): ‘Radon is an odourless, colourless and tasteless natural radioactive gas that is released from underground and can accumulate inside buildings, posing a threat to public health. The World Health Organisation has, in fact, classified it as a class 1 carcinogen. Suffice it to say that long-term exposure to this gas is the second leading cause of lung cancer after cigarette smoking. In Switzerland, it is estimated that around 10% of lung cancers are attributable to radon, with a particular incidence in the Ticino and Graubünden regions, where radon concentrations are higher due to the constitution of the subsoil. It is therefore estimated that radon causes 200-300 deaths in Switzerland each year'.

‘Radon measurement is not only a preventive measure, but plays a key role in reducing the risk of lung cancer,’ Luca Pampuri continues. ‘In particular, it is essential in highly frequented environments such as schools, kindergartens, hospitals and private homes. As the Radon Competence Centre (CCR), we have been carrying out numerous activities in line with our research and public health protection objectives since 2007. For this reason, we recommend that all property owners, especially in the areas most at risk, carry out an accurate measurement by ordering the relevant instrumentation or contact us for advice'.

The CCR’s activities are not limited to measurement initiatives. The Centre is, in fact, involved in research projects at federal and international level, and is also involved in education, both within degree courses for engineers and architects and through refresher courses for technicians and professionals. In addition, the CCR offers services for the territory, for example as a measurement service recognised by the Federal Office of Public Health.

Over the years, the CCR has contributed to research projects of national importance. These include the publication of technical texts for specialists, offering concrete solutions and guiding them in the selection of the most suitable materials for remediation or prevention work.

Since 2021, the CCR has extended its range of activities by also focusing on indoor air quality and taking on the role of Italian-speaking antenna for the French-speaking and Ticino Observatory on Indoor Air Quality.