IoT module for air quality measurement

The main purpose of this paper is to present an embedded system designed for monitoring indoor and outdoor air quality, using more specific sensors for a higher detection range of pollutants. The system is based on an ESP32 microcontroller, which collects information from the sensors, then displays it on an LCD for local viewing. We are using Internet of Things technology in order to allow data retrieval and analyze the evolution of different measured parameters. From the sensors available on the market, we have tried to select those that offer the best specifications and high measurement accuracy at an affordable price. Also, most of the sensors use the I2C communication protocol, in order to minimize pin allocation.