시간활동양상 및 이산화탄소 농도를 이용한 한국 주택 환기량 추정

Estimation of Ventilation Rates in Korean Homes Using Time-activity Patterns and Carbon Dioxide (CO₂) Concentration

Objectives: The purpose of this study was to estimate the ventilation rate of residential homes in Korea through tracer gas methods using indoor and outdoor concentrations of carbon dioxide (CO₂) and CO₂ generation rates from breathing. Methods: In this study, we calculated the number of occupants in a home by time through data on the average number of people per household from the Korean National Statistical Office and also measured the amount of CO₂ generation by breathing to estimate the indoor CO₂ generation rate. To estimate the ventilation rate, several factors such as the CO₂ generation rate and average volume of residential house provided by the Korean National Statistical Office, indoor CO₂ concentrations measured by sensors, and outdoor CO₂ concentrations provided by the Korea Meteorological Administration, were applied to a mass balance model for residential indoor environments. Results: The average number of people were 2.53 per household and Koreans spend 61.0% of their day at home. The CO₂ generation rate from breathing was 13.9±5.3 L/h during sleep and 15.1±5.7 L/h in a sedentary state. Indoor and outdoor CO₂ concentrations were 849 ppm and 407 ppm, respectively. The ventilation rate in Korean residential houses calculated by the mass balance model were 42.1 m³/h and 0.71 air change per hour. Conclusions: The estimated ventilation rate tended to increase with an increase in the number of occupants. Since sensor devices were used to collect data, sustainable data could be collected to estimate the ventilation rate of Korean residential homes, which enables further studies such as on changes in the ventilation rate by season resulting from the activities of occupants. The results of this study could be used as a basis for exposure and risk assessment modeling.