Notes: In the beginning of 2016 Radiation Safety Centre of Latvia (RSC) created a large scale information campaign about the influence of radon and distributed free radon detectors for radon measurements in 487 dwellings, covering the entire territory of Latvia. At the end of 2016, 459 dwellings returned their detectors. The average radon concentration in dwellings in Latvia is 60-70 Bq/m3. In 2016 – 2017 RSC organized radon measurements in workplaces and public buildings, 955 detectors (alpha track detectors) in 209 institutions/companies (243 buildings). Mainly distributing detectors in universities and colleges, schools, preschool educational institutions, drinking water suppliers, food companies, industrial companies, museums and hospitals. According to the results (from 75 workplaces, 97 schools and 70 kindergartner buildings): the average level of radon concentration in workplaces is 47 Bq/m3, in schools is 90 Bq/m3, in kindergarten is 67 Bq/m3.  