利用流气式^(220)Rn源刻度便携式连续测氡仪

The Calibration of Portable Radon Meter by Using ^(220)Rn Flow-Through Source

为实现便携式连续测氡仪准确测量^(220)Rn活度浓度,采用不同活度的流气式固体^(220)Rn源对便携式连续测氡仪测^(220)Rn的内腔灵敏度和相对灵敏度在不同采样流率下进行了刻度。研究表明:便携式连续测氡仪测^(220)Rn的内腔灵敏度与采样流率和源的活度总体趋势上是不相关的,其均值为(5.595±0.649)×10^(-3)(Bq·m^(-3))·min^(-1);便携式连续测氡仪测^(220)Rn的相对灵敏度随采样流率的增加呈上升趋势,且上升趋势逐步变缓。

To achieve accurate measurement of ^220Rn activity concentration by using radon monitor,this study was carried out theoretically and experimentally.Using high emanation rate,stable and the activity are 17.1 Bq、64.0 Bq^220Rn solid source to provide different ^220Rn activity concentration.The cavity sensitivity of radon monitor measuring ^220Rn and the impact of sampling pump flow rate to relative sensitivity was discussed.The result shows that sampling flow rate and source activity has little to do with the cavity sensitivity of radon monitor,and the mean value is（5.595 ± 0.649） × 10^-3（Bq·m^-3） ·min^-1.With the increase of the sampling pump flow rate,the relative sensitivity will also increase,and the rising trend gradually slows down.