📄 Sciences Methods and Technologies
International Journal (SciMeTech)

Volume 1 · Issue 2 · 2025
ISSN: 3085-5284
Smart Indoor Air Quality Monitoring System Using an ESP32 Microcontroller with DHT11 and MQ135 Sensors
Salma Lamribah, Imane Mahaimeur
Pages 32–36 · Ecole Supérieure de Technologie d'Essaouira, Department of Mathematics and Computer Science, Cadi Ayyad University, Essaouira, Morocco · Polydisciplinary Faculty, Laboratory of Physics, Energy, Environment and Applications, Cadi Ayyad University, Sidi Bouzid, B.P. 4162, Safi, Morocco
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Abstract
Indoor air pollution is a growing concern, especially given the significant amount of time people spend indoors. This paper presents a smart air quality monitoring system based on the ESP32 microcontroller, which integrates DHT11 and MQ135 sensors to track temperature, humidity, and harmful gas levels in real time. The collected data is visualized via a web dashboard that refreshes every 5 seconds and includes dynamic alerts to inform users about air quality levels. Designed to be low-cost and user-friendly, this system supports healthier environments in homes, schools, and small offices. While the system is effective, limitations such as sensor accuracy and power dependency offer avenues for future improvement.
Keywords: IoT, ESP32, Air Quality, Sensors, Web Dashboard

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SciMeTech · Volume 1, Issue 2 · 2025 · ISSN 3085-5284