PU-239(240), PU-238, SR-90, RU-103 AND CS-137 CONCENTRATIONS IN SURFACE AIR IN AUSTRIA DUE TO DISPERSION OF CHERNOBYL RELEASES OVER EUROPE

After the reactor accident at Chernobyl on 26 April 1986, Austria, sit uated in the central part of Europe, was one of the most stricken coun tries. Radionuclide concentrations in surface air have been measured a t five different sampling stations, viz. in Vienna, Linz, Salzburg, Br egenz and Klagenfurt, during the period 28 April-9 May 1986. In additi on to the results of the gamma-spectroscopic measurements of Ru-103 an d Cs-137 data for Pu-239(240), Pu-238 and Sr-90 determined by radioche mical analyses of the same air filters are presented. These results sh ow that in Austria generally most of the Cs-137 and Ru-103 contaminati on occurred before 2 May, whilst most of the Sr-90 and Pu-239(240) con tamination took place between 2-5 May. Initially Ru-103/Cs-137 ratios of approximately 2 could be observed, which later decreased to 0.3-0.6 and increased again after 2 May, up to as high as 5. The ratios of Sr -90/Cs-137 remained between 0.004 and 0-017, those of Pu-239(240)/Cs-1 37 between 1.3 x 10(-6) and 2 x 10(-5).