Measurement radonu Strakonice, Prague, Písek, Blatná, Prachatice, Příbram, Dobříš, Sedlčany, Benešov, Tábor, Beroun, Kladno, Slaný, Louny, České Budějovice, Plzeň, Klatovy and the whole Czech Republic. We measure radon on land for building permits, in interiors for building approvals, we propose anti-radon measures.