Practical Analysis of Radon Protection Methods in an Underground Project

Abstract

Radon and its progeny are gaseous radioactive substances, colorless and odorless, widely present in ground buildings and underground projects. Especially in underground engineering, due to the continuous decay of uranium contained in the soil, radon will be continuously released from the soil into the air in the underground engineering, causing continuous internal exposure damage to the staff. Radon is the most important contributor to the natural background radiation exposure of humans, and the internal exposure dose caused by inhalation of radon and its progeny accounts for more than half of the total natural radiation dose received by the public (Charles in J. Radiol. Prot. 21:83–86, 2001 [1]). Based on the main properties of radon, three common radon reduction measures were tested in an underground project, and the optimal radon reduction method was studied. Radon and its daughters are gaseous radioactive substances widely existed in underground projects, which will seriously harm workers’ healthy. Based on the main properties of radon, three common measures for radon concentration reducing purposes, e.g. ventilation, shielding and adsorption, were tested and validated in an underground project. The statistical analysis results show that ventilation costs lower and its radon-reducing effect behaves better. By ventilating 3 times per hour, the radon concentration can be reduced by 65.6%. Wearing a mask can also effectively prevent radon from entering the body through the respiratory tract. Mask of type Nanhe 95 can filter 89.17–95.82% of radon and its daughters. In contrast, for underground projects with big room, radon was released continuously, and small-scale radon adsorption device would do little on radon concentration reduction.