RADIOACTIVITY MEASUREMENTS IN AIR OVER EUROPE AFTER THE CHERNOBYL ACCIDENT

A comprehensive European data set of radioactivity in air caused by the accident at the Chernobyl nuclear power plant is presented. For the first 2 weeks after the beginning of the release, levels of particulate I-131, Cs-134 and Cs-137 (85 locations) and of total I-131 (10 locations) are given. All data are stored in a computerized data base. For the first time the passage of the Chernobyl cloud over Europe is mapped after re-averaging the time histories in each location to produce coherent daily concentrations. Cs-134/Cs-137 ratios were analyzed: the 'European' average ratio calculated from 1239 samples is 0.55, with a standard deviation of 0.25. © 1990.