Optimizing indoor air quality and noise levels in old school classrooms with air purifiers and HRV: A CONTAM simulation study

• Published in: Journal of Building Engineering 2023-08, Vol.73, p.106645, Article 106645
• Main Authors: Na, Hooseung, Choi, Haneul, Kim, Haseong, Park, Dongjun, Lee, Joosang, Kim, Taeyeon
• Format: Article
• Language: English
• Subjects: Air purifier; CONTAM; Heat recovery ventilation (HRV); Indoor air quality; Noise
• ISSN: 2352-7102; 2352-7102
• DOI: 10.1016/j.jobe.2023.106645

Efforts at the national level are being made to improve the indoor air quality of school classrooms. Air purifiers and heat recovery ventilation (HRV) are commonly used to achieve this objective. However, the noise generated by these systems often disrupts classes, leading students to be hesitant in utilizing them. This study proposes an operating method to minimize noise while improving indoor air quality through CONTAM simulations. The method involves operating the HRV in low wind mode during class time and strong wind mode during break time. The dissatisfaction rate (measured by the duration in which the CO2 concentration exceeded 1500 PPM) was minimal, with a rate as low as 0.2% over one year of occupancy. In the case of fine dust PM2.5, operating the air purifier 1 h earlier than occupancy time, while maintaining the existing HRV operation, resulted in a low dissatisfaction rate (PM2.5 concentration exceeded 15 μg/m3 during occupancy time for one year) of 2.6%. According to student reports, the use of weak wind mode during class and strong wind mode during break time resulted in reduced annoyance from the equipment noise. They expressed overall contentment with the experimental noise level, as long as the indoor air quality was improved. The study findings provide an effective and feasible approach to satisfying both noise and indoor air quality requirements. Furthermore, the methodology adopted in this study can be valuable for developing appropriate air purifier facility capacities in different schools. •Operating method considering the noise of air purifiers and HRV in a classroom.•Priority: 1) Noise, 2) Carbon dioxide (CO2), 3) Fine dust (PM2.5).•Annual CO2 and PM2.5 concentration analysis conducted through simulation.•High satisfaction with noise and air environment based on measurement and simulation.•Our methodology will be helpful for calculation for the appropriate capacity of air purifiers and HRV in various schools.