A Low-Cost Distributed Air-Quality Sensor Network Built with ESP32 Boards

Abstract

This study presents a budget-friendly air-quality monitoring setup for school classrooms using ESP32 microcontrollers and optical dust sensors. The author assembled eight nodes, calibrated them against a reference monitor, and logged PM2.5 values over six weeks. The network achieved an average absolute error of 4.8 µg/m³ after calibration and helped identify ventilation periods associated with elevated particle levels. The work demonstrates an approachable pathway for high-school students to conduct meaningful environmental sensing projects.