Protection from radon

Radon is a noble radioactive gas, odorless and colorless, produced by the radioactive decay of radium.
Radon is present in different quantities in the indoor air of all buildings and mainly comes from the soil and, to a lesser extent, from the building materials (especially in case of thick walls).
Many epidemiological studies have found that continuous exposure to radon increases the risk of developing a lung cancer. The extent of the risk increases with the radon concentration level and with the duration of exposure. With the same exposure to radon, smokers are much more at risk than non-smokers, due to sinergy effects of radon and cigarette smoking. In Italy, exposure to radon is responsible (according to estimates by the Italian National Institute of Health (ISS) of more than 3000 cases (link to the Italian website) of lung cancer every year.
Since 2005, the ISS has coordinated the Italian National Radon Plan (promoted in 2002 by the Ministry of Health) and manages the National Radon Archive.
A new National Radon Action Plan is in a advanced stage of preparation. This new plan is required by the Legislative Decree 101/2020 that has transposed the European Directive 2013/59/Euratom on basic safety standards for protection from ionizing radiation.
As required by the Legislative Decree 101/2020 (art. 14, par. 1), the ISS provides information to the population about:

• radon concentration levels in dwellings and workplaces (link to the Italian website)
• health effects and risks, for both smokers and non-smokers (link to the Italian website)
• how to measure radon concentration level and how to reduce it (link to the Italian website)

These and many other information on radon (actually available since 2013 in the framework of the Italian National Radon Plan) can be found on https://radon.iss.it (link to the Italian website) and they will be updated regularly. 
Protection from radon is one of the themes of the collaboration of the National Center for Radiation Protection and Computational Physics of ISS with the World Health Organization (WHO), within the WHO Collaborative Centre “Radiation and Health”, which is active since 2018. WHO documents on protection from radon can be found following the links below:

Guidelines and documents World Health Organization (WHO)

Handbook on Radon Indoor: a public health perspective 2009