Department of Cellular and Integrative Physiology, School of Medicine, Fukushima Medical University, 1 Hikarigaoka, Fukushima 960-1295, Japan.
Environ Health Prev Med. 2013 Jul;18(4):261-6. doi: 10.1007/s12199-012-0314-6. Epub 2012 Nov 4.
One and a half years have passed since the Fukushima Daiichi nuclear power plant disaster. The environmental radiation dose rate was not critical, but an existing exposure situation has been identified in a large part of Fukushima Prefecture. Although people continue to live and work in the contaminated area, they are not provided with sufficient information to reduce their exposure to radiation by themselves. In this study, we attempt to evaluate the efficiency of radiation shielding by using everyday items widely available to people.
NaI scintillation and Geiger-Müller survey meters were used to measure the radiation dose of (1) contaminated soil and (2) soil covered with commonly available items.
In the soil at a depth of 10 cm from the surface, the radiation dose rate decreased from 3.36 to 0.65 μSv/h, and the count rate decreased from 3,120 to 352 cpm. Both the radiation dose rate and count rate reduced when the soil was covered with everyday items, such as a magazine more than 20 mm thick, a polystyrene foam board, and a wooden board of the same thickness.
To protect residents from unnecessary radiation exposure in the existing exposure situation, covering contaminated soil with a wooden board or a magazine, either of them 20 mm thick, is useful to reduce the radiation dose.
福岛第一核电站事故发生已过去 1 年半。虽然环境辐射剂量率未达到危险水平，但在福岛县的大部分地区已发现现有的辐射暴露情况。尽管人们继续在污染地区生活和工作，但并未向他们提供足够的信息来自行减少辐射暴露。在本研究中，我们试图通过使用人们广泛拥有的日常用品来评估辐射屏蔽的效率。
使用碘化钠闪烁体和盖革-弥勒计数器来测量（1）污染土壤和（2）用常见物品覆盖的土壤的辐射剂量。
在地表以下 10 厘米的土壤中，辐射剂量率从 3.36 降至 0.65 μSv/h，计数率从 3,120 降至 352 cpm。当用日常用品如超过 20 毫米厚的杂志、聚苯乙烯泡沫板和相同厚度的木板覆盖土壤时，辐射剂量率和计数率均降低。
为了保护居民免受现有暴露情况下的不必要辐射暴露，用 20 毫米厚的木板或杂志覆盖污染土壤有助于降低辐射剂量。
