Journal of Korean Institute of Architectural Sustainable Environment and Building Systems ISSN:1976-6483(Print) 2586-0666(Online) 한국건축친환경설비학회논문집

This study aimed to quantitatively estimate the removal of indoor air pollutants using a mechanical ventilation system that was installed in typical apartment houses in Korea. For CO₂, the Korean indoor air quality standard (1,000 ppm) could not be maintained even with 1.5 ACH. The time for reducing the CO₂ concentration 3,000 ppm to 1,000 ppm were measured to be 416, 126, 89, and 58 minutes, for 0.0, 0.5, 1.0, and 1.5 ACH, respectively. For radon, it was difficult to lower the indoor concentration with only the natural decay method, and with the 0.5 ACH ventilation rate (mechanical ventilation), the indoor radon could not be effectively controlled. The removal rates were 23.5% for 0.5 ACH, 30.4% for 1.0 ACH, and 39.7% for 1.5 ACH after 2 hours of ventilation. The results of these experiments show that it is difficult to meet the indoor air quality standard with only 0.5 ACH ventilation. In addition, more than 1.5 ACH ventilation could be also necessary to remove high-level indoor air pollutants effectively. Moreover, it was confirmed that indoor air pollutant concentrations should be lowered using mechanical ventilation systems because radon is radioactively decayed, but inflow and accumulation from emission sources affecting the indoor space are present.