EML surface air sampling program. The quality of radionuclide analysis, 1980

Results for reference samples, blanks, and duplicates used to judge the quality of gamma spectrometric analyses of surface air filter samples collected during 1980 and of radiochemical analyses of filters collected during the end of 1979 as well as 1980 are reported and evaluated. For most nuclides accuracy and precision were within +-20%. Because most Zr-95 results would be non-detectable at count time, Zr-95 was not added to the reference samples. Ce-144 results for reference samples displayed a wide variation in percent deviation from the expected values. A negative bias on Be-7 reference samples continues to be observed. Cs-137 and Ce-144 show a negative bias as well. The results for Sr-90 on reference samples were quite poor and are of great concern. As has been observed in recent years, many of the Zr-95, Cs-137 and Ce-144 activities on duplicates are non-detectable. One set of duplicates showed widely discordant results for Sr-90 and Pu-239. This appears to be an anomalous result rather than a systematic problem