Kavasi N, Janik M, Prasad G, Omori Y, Ishikawa T, Yonehara H
National Institute of Radiological Sciences, 4-9-1, Anagawa, Inage-ku, Chiba-shi 263-8555, Japan.
Radiat Prot Dosimetry. 2012 Nov;152(1-3):150-3. doi: 10.1093/rpd/ncs212. Epub 2012 Aug 26.
A new thoron ((220)Rn) experimental room (TER) was established at National Institute of Radiological Sciences in 2011 to respond to the appearance of new passive devices for (220)Rn and its progeny ((212)Pb, (212)Bi) measurement. The room volume is 21.7 m(3) with a low air exchange rate, 0.016 h(-1). Environmental parameters, such as temperature, relative and absolute humidities, wind speed, aerosol distribution and concentration, are monitored, but not controlled. Commercially available lantern mantles (500 pcs), which can generate maximum concentrations of 6000 Bq m(-3) of (220)Rn and 2000 Bq m(-3) of its progeny, are used as a (220)Rn source. Based on preliminary results from the TER, stable and homogenised concentrations of (220)Rn and its progeny can be ensured; therefore, in the near future the room will be used for testing measuring instruments.
2011年，日本国立放射科学研究所设立了一个新的钍射气（(220)Rn）实验室，以应对用于测量(220)Rn及其子体（(212)Pb、(212)Bi）的新型被动式装置的出现。该实验室容积为21.7立方米，空气交换率较低，为0.016次/小时。对温度、相对湿度、绝对湿度、风速、气溶胶分布和浓度等环境参数进行监测，但不进行控制。使用市售的灯罩（500个）作为(220)Rn源，其可产生的(220)Rn最大浓度为6000 Bq/立方米，其子体最大浓度为2000 Bq/立方米。基于该实验室的初步结果，可以确保(220)Rn及其子体浓度稳定且均匀；因此，在不久的将来，该实验室将用于测试测量仪器。
