Abstract: In this paper, the monitoring results and variation trends of tritium in air around Ningde NPP from 2014 to 2022 were analyzed. The monitoring results of the baseline, the background survey results and other nuclear power plants in China were compared and analyzed, and the correlation with tritium emission of gaseous effluent from Ningde NPP were studied. The analysis results show that the measured values of tritium in air of the monitoring points around Ningde NPP range from <2.8 to 56 mBq/m³. The detection activity concentration of tritium in air around the NPP site generally have an increasing trend. The measurement value at Niulanggang, which is closest to the NPP site, is higher than other points and significantly higher than the background survey results, but still far below the clearance level stipulated by regulatory body. Tritium monitoring results at various locations over the years have a strong correlation with the tritium emission of the gaseous effluent of the nuclear power plant, indicating that the tritium level in air around the Ningde NPP may be affected by the tritium emission of the gaseous effluent of the nuclear power plant.

Key words: nuclear power plant, tritium in air, gaseous effluent, supervision monitoring