Abstract: The response ability and stability of radon detector are the key factors to ensure the effectiveness of seismic monitoring and prediction. As a new method of moniroing Seismic underground fluid, the response ability and stability of electrostatic collection diffusion radon detector are related to the applicability of continuous seismic monitoring. In order to meet the detection requirements of the diffusion sampling radon for seismic monitoring, this study designed a test equipment for diffusion sampling radon detector based on the high radon content well water sample of Jiujiang No.2 well, and tested the response ability and stability of a electrostatic collection diffusion sampling radon detector under high concentration. The results show that the concentration of radon in the test device can switch between 0-120 kBq/m³ and can be relatively stable for a long time under the target concentration. The response time of the radon detector at high concentration is 2 hours and the stability is less than 5% for 8 h. The test device consists of crossflow module, degassing module, drying bottle, test chamber, measuring standard, air pump, etc, which can be used to test the response ability and stability of seismic monitoring diffusion sampling radon meter.

Key words: seismic monitoring, diffusion sampling, radon detector, responsiveness, stability