Notes: There is no separate requirement directly for radon measurement in new dwellings and in dwellings with high public occupancy. The same requirement specified in the point 39 of the Radiation Safety Norms is valid for all cases. It stipulates that during designing the residential and public buildings it should be envisaged that the summary of the annual average equilibrium activity concentration due to 222Rn and 220Rn daughter isotope (222Rn + 4.6 220Rn) shall not exceed 100 Bq/m3.  