低气压地区闪烁室和 PQ2000测氡仪的刻度校准研究

摘要

气压是影响闪烁室和PQ2000型测氡仪准确测量的主要因素之一。为准确测量气压为89．0 kPa的中国西北某低气压地区的氡浓度值，有必要对测氡设备进行刻度校准。通过在该地小型氡室内开展的刻度校准研究，显示PQ2000测氡仪的测量值与约定真值之间符合幂函数分布，校准因子随氡浓度增加呈幂函数增长趋势；闪烁室在109．0 kPa和89．0 kPa的两地刻度因子的相对偏差接近5％，气压修正不容忽视。%Air pressure is an important factor that influences measurement accuracy of radon detectors,such as flash room and PQ2000.In order to accurately measure radon concentration in region that the air pressure is only 89.0 kPa.The radon detector must be recalibrated.Flash room and PQ2000 were calibrated in small standard radon chamber in that region.The results showed that calibration factor of PQ2000 logarithmically increased with radon concentration.If the scintillation counter was calibrated in two regions that air pressure is 109.0 kPa and 89.0 kPa respectively, deviation of the calibration is about 5%.According to the experiment results, air pressure correction can not be ignored.