[en] Historical data on radioactivity in air and precipitation samples have been collected and analysed from study sites in Norway. The purpose of the study was to investigate the correlation between air concentration, precipitation and deposition, and identify areas with high deposition. Areas with high precipitation have been compared with monitoring stations in other countries. The base data contains measurements of total beta in air and precipitation on a daily basis for the period 1956-1982. Radioactive fallout correlated strongly with annual precipitation which varies from 280-4200 mm per year in Norway. The deposition of ¹³⁷ Cs was calculated to be 3.23 ± 1.20 kBq/m ² per 1000 mm annual precipitation for the period 1955-1975. Also, the relationship between total beta and ¹³⁷ Cs has been investigated, in order to estimate the age of fallout. The age of fallout in Norway ranges from 3-9 months during the test periods, which is considerably shorter than the global average, where the mean residence time for debris in the lower stratosphere is estimated to be 1.3 years. There is no evidence of local fallout from tests on Novaya Zemlya reaching Norwegian areas. (au)