中国水氡观测历经50余年，观测仪器老化严重。2011年至今分别引入新生产的3批次64套FD-125型氡钍分析仪。经过仪器测试、地震台站运行以及多次现场实验，发现：该仪器定标器阈值不应按照地震水文地球化学观测技术规范选定的2 V，需选择0.7 V甚至更低阈值，才能保证测值的可靠稳定，保障水氡观测继续发挥防灾减灾作用。
Radon is inert gas of radioactive decay arising from the rock and soil of crust, which mainly contain the precursors of earthquakes. The problems of instruments aging in dissolved radon monitoring have become more serious in the near days during the continued using over 40 years. 64 sets of FD-125 radon and thorium analytical instrument have been introduced by the projects of background field and Instrument renewal and transformation. We carried on several factory testing and fled experiments in observation stations. The test results show that, on the condition of a relatively low threshold (eg, 0.5 V, or even lower) of the scalar, the results are more stable and reliable. In the conditional case, after choosing suitable threshold, the measurement of high-voltage plateau curve may carry out using radium source or radon gas source. In this process, special attention is being given to avoid light in daily maintenance.
2017,38(3): 134-139 收稿日期：2016-08-22
DOI：10.3969/j.issn.1003-3246.2017.03.023
基金项目：全国地下流体物理量观测台网产出（项目编号：1640410320103）
作者简介：樊春燕(1985-),女,工程师,主要从事地震地下流体数据处理与观测应用研究工作.
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