Smart IoT based Air Quality Monitoring and Alert System using WEMOS D1

Monitoring air quality in real time becomes very relevant, especially for health and safety considerations within industrial domains and closed environments. This paper introduces the design of a smart IoT system for air quality monitoring and alerting focused on WEMOS D1 microcontroller and MQ-series sensors: MQ-135, MQ-9, and MQ-214, and are designed to measure concentrations of neutral pollutants such as ammonia, alcohol, carbon monoxide, and smoke. Sensor data are sent via a customized web application for user visualization, allowing the option to view real-time readings and issue alerts on crossing threshold limits. It specifies high-accuracy detection against response time of less than five seconds. The low-cost nature, ease of installation, and immediate alerts tailor this system perfectly for immediate occupational safety monitoring in factories, labs, and indoor workplaces.