Yoshida M, Yoshizawa M, Minami K
Department of Health Physics, Japan Atomic Energy Research Institute, Ibaraki-Pref.
Radioisotopes. 1990 Sep;39(9):396-9. doi: 10.3769/radioisotopes.39.9_396.
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.
根据ISO报告7506-1中定义的污染源效率，针对地板、聚乙烯、经涂片测试的滤纸和不锈钢板等材料进行了实验测定。使用了147Pm、60Co、137Cs、204Tl和90Sr-Y这5种核素研究效率的β射线能量依赖性，并使用241Am作为α射线发射体。评估了无窗2π比例计数器测量中的充电效应，以获得可靠的表面发射率。除了两种情况外，对于不可渗透材料，即使对于147Pm，测量的效率也超过0.5。根据目前的结果，ISO建议被证明足够保守。
