Smart Air Quality Monitoring and Management System

This paper presents a Smart Air Quality Monitoring and Management System implemented using an ESP32 microcontroller, MQ-7 gas sensor, DHT11 temperature and humidity sensor, Firebase Realtime Database, Telegram notifications, and relay-based fan control. The prototype integrates sensor acquisition, cloud transmission, software threshold classification, remote notification, and local actuation in a single platform. The implementation provides a foundation for remote observation of environmental measurements and demonstrates how programmed threshold conditions can be used to trigger notifications and control a fan. Its operational reliability must be established through repeated tests and quantitative measurements of data transmission, alert delivery, and relay response. The current gas-sensor scaling method does not provide a validated CO concentration in ppm. Future work will include calibration against a reference gas-measurement instrument, improved handling of sensor and network failures, reliable notification generation during category transitions, and secure communication with cloud and notification services. Further experiments should assess long-term stability and the effectiveness of fan-based ventilation. The prototype is a starting point for connected environmental monitoring and is not a replacement for certified gas-detection or air-quality measurement equipment

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