[Efficiencies of contamination source for flooring and some materials used in unencapsulated radioactivity handling facilities].
The efficiencies of contamination source, defined in ISO Report 7506-1, were experimentally determined for such materials as flooring, polyethylene, smear-tested filter paper and stainless steel plate. 5 nuclides of 147Pm, 60Co, 137Cs, 204Tl and 90Sr-Y were used to study beta-ray energy dependence of the efficiency, and 241Am as alpha-ray emitter. The charge-up effect in the measurement by a window-less 2 pi-proportional counter was evaluated to obtain reliable surface emission rate. The measured efficiencies for non-permeable materials, except for two cases, are more than 0.5 even for 147Pm. The ISO recommendations were shown to be conservative enough on the basis of present results.
Yoshida
M
M
Department of Health Physics, Japan Atomic Energy Research Institute, Ibaraki-Pref.
Yoshizawa
M
M
Minami
K
K
D005374:Filtration; D005430:Floors and Floorcoverings; D010209:Paper; D011095:Polyethylenes; D011848:Radioactive Pollutants; D011868:Radioisotopes; D013193:Stainless Steel
D011095:Polyethylenes; D011848:Radioactive Pollutants; D011868:Radioisotopes; D013193:Stainless Steel