Development of an IoT-based Real-Time Air Quality Monitoring Device

Over the last few decades, the quality of air has been deteriorating at an alarming rate leading to demise of nearly seven million people annually worldwide. In the midst of the above worrisome facts citizens across the globe deserve transparency about the quality of the environment they live in, so that appropriate decisions could be taken before it is too late. Keeping this in mind a prototype for an air quality monitoring system has been developed in this work. The proposed air quality monitoring device comprises of a NodeMCU ESP32, a MQ-135 gas sensor and a DHT-11 temperature and humidity sensor module. As compared to other counterparts available, our proposed system gives an upper hand in terms of small size, efficient power usage and cost. The sensors record the data and send it to the NodeMCU acting as the base station of the overall setup. Having an inbuilt microcontroller and an onchip Wi-Fi transceiver, the NodeMCU not only serves the purpose of monitoring the data but also sending it to a remote server empowering tremendous scope for physical world to be communicated at a very fine and detailed level. The gas sensor records the concentration of toxic gases like NOx, CO2, benzene, smoke and gives an overall air quality parameter. If the concentration of the toxic gases exceeds a standard value an alert message is also displayed on the server. The integrated system could possibly be a big yes for the smart cities to justify steps to control pollution level in the years to follow.