A Real-Time Indoor Air Quality Monitoring System for Hospitals

Air pollutants present indoors can significantly affect the health of room occupants as indoor air pollutants can often be present at higher concentrations than those found outdoors. This project improved a previously established indoor air quality monitoring system for hospitals by adding local data storage and utilizing a self-organizing wireless mesh network which enhanced the system's scalability and reliability. This project also builds on the previous system by improving power efficiency through the use of sensor nodes with a low-power microcontroller model and an improved data transmission algorithm. The local storage system implemented on the sensor nodes and gateway node allows the handling and visualization of sensor readings even when offline. The project implemented a battery monitor with a smaller rechargeable module to be used as a back-up power in case of power interruptions and to improve its portability. Onsite deployment showed that relative humidity, temperature, CO2, TVOC, SO2, and PM2.5 levels indicated good to moderate air quality, with observed spikes in CO2, TVOC, and PM2.5 correlating to occupant influx, ongoing construction, proximity to vehicular traffic sources, and disinfection procedures.