Overview and details of the sessions of this conference. Please select a date or location to show only sessions at that day or location. Please select a single session for detailed view (with abstracts and downloads if available).
The relationship between the indoor environment and the health of building occupants is complex. Local air quality, occupant’s activities, building construction, and HVAC design are just a few of the variables that make it difficult to provide optimal indoor air quality. This session will focus on strategic CO2 monitoring & sensor placement, ventilation rates, and air filter selections that lead to improved indoor air quality. ASHRAE Standard 241 will be referenced when presenting strategies for various programmatic space types. The importance of CO2 sensor placement in naturally ventilated classrooms will also be discussed.
Presentations
Analysis of Airborne Pathogen Mitigation Measures to Meet ASHRAE Standard 241 in Key Space Types
Cary Alexander Faulkner
Pacific Northwest National Laboratory, United States of America
New indoor air quality standards, such as ASHRAE Standard 241 (S241), have been proposed for controlling infectious aerosols in buildings. Further research is needed to assess the tradeoffs of different measures when designing to S241 for different space types. To address this gap, this research models measures including increasing outdoor air ventilation, upgrading HVAC filtration, using portable air cleaners (PACs), and installing in-duct, upper-room, or whole-room germicidal ultraviolet (GUV) systems for office, classroom, dining, and healthcare waiting room space types in seven climate zones. The findings offer practical guidance to meet S241 for key space types, highlighting key design challenges.
Sensor Placement Matters: Continuous Monitoring of Vertical CO2 Gradients in a Classroom
Yu Chang, Hongshan Guo, Yichun Li
The University of Hong Kong, Hong Kong S.A.R. (China)
Indoor air quality (IAQ) in classrooms influences student health and performance, with CO2 serving as an indicator of ventilation adequacy. While standards recommend CO2 monitoring at breathing height, real-world sensor placement may compromise accuracy. This study examines vertical CO2 gradients in a natural-ventilated classroom using IoT sensors at floor, breathing zone, and ceiling over two weeks under varying occupancy and HVAC conditions. We observed CO2 gradients up to 75 ppm between floor and ceiling - with the most pronounced disparities occurring during unoccupied periods. These findings points to a risk of misinterpretation from improperly placed sensors, particularly in dynamic classroom environments.
