Impact of Sensor Placement on Indoor Air Quality Monitoring: A Comparative Analysis

This study investigates the impact of sensor placement on the accuracy and responsiveness of indoor air quality (IAQ) monitoring focusing on particulate matter concentrations. Measurements were conducted in a controlled environment using three intercalibrated sensors positioned at different locations: a wall-mounted sensor installed at 1.2 meters above the ground, a sensor placed at the inlet of an air purifier, and a sensor located at breathing height in the center of the room. A particle source was introduced at four different points within the room to simulate varying pollution scenarios. The results revealed that the wall-mounted sensor exhibited delays of up to 200 seconds in detecting peak pollutant concentrations compared to the sensor near the air purifier. Additionally, the wall-mounted sensor consistently recorded lower pollutant levels compared to the other two sensors. The findings underscore the critical importance of strategic sensor placement for accurate and real-time IAQ monitoring. Placing sensors closer to breathing zones and pollution sources provides data that more accurately reflects human exposure risks. The study concludes that wall-mounted sensors may not provide real-time air quality data in dynamic indoor environments. Further research, including computational fluid dynamics (CFD) simulations, is recommended to optimize sensor placement strategies.