Design of a Real-Time Air Quality Monitoring System for Abakaliki Urban Areas

Rapid urbanization and industrial activities in Abakaliki have raised concerns about deteriorating air quality, yet real-time environmental monitoring infrastructure remains largely absent in the city. This study designs a real-time air quality monitoring system for strategic locations in Abakaliki, Ebonyi State, capable of detecting concentrations of carbon monoxide, nitrogen dioxide, particulate matter (PM2.5), and humidity. The system integrates MQ-series gas sensors, a Nova SDS011 PM2.5 sensor, and a DHT22 humidity module with an ESP8266 NodeMCU microcontroller, transmitting data wirelessly to a ThingSpeak IoT cloud platform for real-time visualization. The research design involved site selection based on traffic density and proximity to market areas, followed by prototype assembly, sensor calibration against reference instruments, and three-week continuous field deployment. Results indicate that PM2.5 concentrations at monitored locations exceeded WHO daily guidelines on 68 percent of measurement days, with peak readings occurring during morning market hours. Carbon monoxide levels were consistently highest near generator-powered commercial clusters. Cloud data upload latency averaged 4.2 seconds. The study concludes that low-cost IoT-based air quality monitors provide actionable environmental data for Nigerian urban authorities. Recommendations include expanding the sensor network to cover additional Abakaliki zones and integrating the data feed with Ebonyi State Environmental Protection Agency platforms.