Hirosaki University, 66-1 Hon-cho, Hirosaki, Aomori 036-8564, Japan.
Health Phys. 2012 Apr;102(4):419-24. doi: 10.1097/HP.0b013e31823ecd5c.
An intercomparison on thoron ((220)Rn) measurement was carried out between National Institute of Radiological Sciences, Japan (NIRS), and New York University School of Medicine, USA (NYU). The measurements of (220)Rn concentration at NIRS and NYU were performed by using the scintillation cell method and the two-filter method, respectively, as the standard measurement method. Three types of alpha track detectors based on passive radon ((222)Rn)-(220)Rn discriminative measurement technique were used: Raduet and Radopot detectors were used at NIRS, and four-leaf detectors were used at NYU. In this study, the authors evaluated (220)Rn concentration variation in terms of run for exposure, measurement method, and exposure chamber. The detectors were exposed to (220)Rn gas with approximately 15 kBq m(-3) during the period from 0.75 to 3 d. As a result, the variation of each measurement method among these exposure runs was comparable to or less than that for the two-filter method. Agreement between the standard measurement methods of NIRS and NYU was observed to be about 10%, as is the case with the passive detectors. The Raduet detector showed a large variation in the detection response between the NIRS and NYU chambers, which could be related to different traceability.
日本国立放射科学研究所（NIRS）与美国纽约大学医学院（NYU）进行了氡气（220Rn）测量的比对实验。NIRS 和 NYU 分别采用闪烁室法和双滤膜法作为标准测量方法，对（220）Rn 浓度进行了测量。实验使用了三种基于被动氡（222Rn）-（220）Rn 甄别测量技术的阿尔法径迹探测器：Raduet 和 Radopot 探测器在 NIRS 中使用，四叶探测器在 NYU 使用。在这项研究中，作者根据暴露运行、测量方法和暴露室评估了（220）Rn 浓度的变化。在 0.75 到 3 天期间，探测器暴露在约 15 kBq m（-3）的（220）Rn 气体中。结果表明，各暴露运行之间的每种测量方法的变化与双滤膜法相当或更小。NIRS 和 NYU 的标准测量方法之间的一致性约为 10%，与被动探测器的情况相同。Raduet 探测器在 NIRS 和 NYU 腔室之间的检测响应变化较大，这可能与不同的溯源性有关。
