Ogino Haruyuki, Hattori Takatoshi
Radiation Safety Research Center, Nuclear Technology Research Laboratory, Central Research Institute of Electric Power Industry (CRIEPI), 2-11-1 Iwado-kita, Komae, Tokyo 201-8511, Japan.
Radiat Prot Dosimetry. 2013 Dec;157(3):446-54. doi: 10.1093/rpd/nct146. Epub 2013 Jun 17.
This paper focuses on the surface contamination control of slightly contaminated property after the Fukushima nuclear accident. The operational level for the unconditional release of contaminated properties is calculated in counts per minute (cpm) to enable the use of a typical Geiger-Muller (GM) survey meter with a 50-mm bore, on the basis of the surficial clearance level of 10 Bq cm(-2) for (134)Cs and (137)Cs derived in the previous studies of the authors. By applying a factor for the conversion of the unit surface contamination to the count rate of a survey meter widely used after the Fukushima accident, the operational level for the unconditional release of contaminated properties was calculated to be 2300 cpm on average and 23 000 cpm at the highest-contamination part. The calculated numerical values of the operational levels are effective as long as the typical GM survey meter is used in the radiation measurement.
本文聚焦于福岛核事故后轻度污染区域的表面污染控制。基于作者先前研究得出的(134)Cs和(137)Cs的表面清除水平为10 Bq cm(-2)，以每分钟计数（cpm）来计算污染区域无条件放行的操作水平，以便能够使用孔径为50毫米的典型盖革 - 弥勒（GM）探测仪。通过应用一个将单位表面污染转换为福岛事故后广泛使用的探测仪计数率的因子，计算得出污染区域无条件放行的操作水平平均为2300 cpm，在污染最严重的部分为23000 cpm。只要在辐射测量中使用典型的GM探测仪，计算得出的操作水平数值就是有效的。
