基于单GM计数管的宽量程γ监测仪研究

Wide Range γ Monitor Based on a Single GM Counter

以单GM计数管宽量程探测技术实用化为目的,介绍了单GM计数管宽量程探测技术原理,开发了宽量程探测模块,并基于该探测模块设计了宽量程γ监测仪硬件与软件。对所研制的工程样机进行了实验测试,包括剂量率测试、累积剂量测试及过载测试等。实验结果表明:基于国产J305低量程计数管研制的工程样机测量范围至少包括本底至10 Gy·h-1共8个量级,整个测量范围内固有相对偏差小于7%;当剂量率高于5μGy·h-1时,变异系数小于7%;累积剂量测量相对偏差仅为0.2%;采用大剂量率照射未出现过载现象。基于单GM计数管的宽量程γ监测仪符合剂量监测设备测量要求,可应用于从本底到核事故大范围的γ剂量率监测,在核电行业和辐照站等涉核单位有广阔的应用前景。

To put the wide range detection technology of single GM counter tube into practice,the wide range detection module is developed on the basis of introducing the principle of the wide range detection technology of a single GM counter tube,the hardware and software of wide-rangeγ-detector are designed on this module.The engineering prototype is tested experimentally.The experiment mainly included dose rate test,cumulative dose test,overload testing,etc.The experimental results show that the measuring range of the engineering prototype made of J305 low-range counter is at least 8 orders of magnitude from background to 10 Gy·h-1,and the inherent relative deviation in the whole measuring range is less than 7%,when the dose rate is higher than 5μGy·h-1,the coefficient of variation is less than 7%,and the error of cumulative dose measurement is only 0.2%.The experimental results show that the wide-rangeγ-dose monitor based on a single GM counter can meet the requirements of the dose monitoring equipment,and can be used to monitorγ-dose rate in a large range from background to nuclear accidents.It has broad application prospects in nuclear power industry,radiation stations,and other nuclear-related units.