Smart Campus Air Quality Monitoring: A Real-Time IoT Solution with React Native and Firebase Integration

Abstract

This study aimed to (1) design and develop an IoT-based hardware system for real-time air pollution monitoring, (2) develop an interactive mobile application for reporting and alert notifications, and (3) evaluate the system’s spatial stability and data transmission performance. The proposed framework integrates Internet of Things (IoT) technology with cloud-based database architecture. The sensing node incorporates a SEN55 environmental sensor and an ESP32 microcontroller to collect key parameters, including PM2.5, VOC Index, and NOx Index. Sensor readings are processed using an edge aggregation algorithm to reduce signal noise before being stored in Firebase Realtime Database for real-time synchronization with the “React AQI” mobile application, developed using the React Native framework. The application supports multilingual visualization in Thai, English, and Chinese. Experimental results demonstrated a high average Data Delivery Ratio (DDR) of 94.76%, with data reliability ranging between 95.7% and 97.5%. A 20-day spatial comparative deployment conducted at Building 22 and Building 26 revealed consistent differentiation in pollution levels across locations, with a mean PM2.5 difference of 1.54 µg/m3. The system effectively visualized pollution trends through interactive graphical analytics. These findings indicate that the proposed framework serves as an innovative prototype for Smart Health management within higher education institutions, aligned with the global Smart Campus paradigm.