Study on an on-site radon-in-water measurement system based on degassing membrane

• Published in: Radiation measurements Vol. 131; p. 106231
• Main Authors: Wang, Yunxiang, Zhang, Lei, Wang, Jingbo, Guo, Qiuju
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.02.2020
• Subjects: Continuous measurement; Degassing membrane; Electrostatic radon monitor; Lower limit of detection; Radon-in-water; Radon-in-water; Continuous measurement; Electrostatic radon monitor; Lower limit of detection; Degassing membrane
• ISSN: 1350-4487; 1879-0925
• DOI: 10.1016/j.radmeas.2019.106231

Radon-in-water is an important tracer in hydrology, oceanography and geology, where a demand for fast response and long-term continuous measurement of radon-in-water concentration on-site is necessary. In this paper, an on-site radon-in-water measurement system based on a degassing membrane, an electrostatic radon monitor and a water temperature sensor is presented, and calibration experiment is carried out. The relative degassing efficiency of the degassing membrane was studied using self-made radon-in-water standard, which gives the result of (97.1 ± 7.3) %. The sensitivity of the measurement system is (3730 ± 190) cph/(Bq/L), and the lower limit of detection is 0.005 Bq/L, with 10 min cycle at 25 °C water temperature. The response time of the measurement system is about 26 min, which is independent of the water flowrate within the range of 0.5–2.5 L/min. Using this measurement system, field measurements were carried out on tap water and deep well water. And the measurement system has been successfully used in the continuous monitoring of radon-in-water concentration at a seismic station in Beijing. •An on-site radon-in-water measurement system with extraordinary performance.•High sensitivity, low LLD and fast response.•Flexible measurement cycle from 1 min to 2 h.•Suitable for continuous radon-in-water monitoring in seismology research.