“Design and Experimental Analysis of a Low-Cost Multi-Gas Air Quality Monitoring System with MQ135 Sensor Using Arduino”

This project focuses on the measurement and analysis of multi-gases such as carbon dioxide (CO₂), alcohol (ethanol), benzene, and ammonia using a low-cost gas detection system based on Arduino. The main aim is to develop an affordable and easy-to-use system that can monitor harmful gases in the environment. In this system, MQ135 gas sensor is connected to an Arduino microcontroller to detect the presence and concentration of gases. The sensor sends data to the Arduino, which processes the information and displays the results. The device is tested using gases like carbon dioxide (CO₂), alcohol (ethanol), benzene, and ammonia to check its performance and accuracy. The results show that the system can successfully detect these gases and provide useful information about their levels. The proposed system is low-cost, simple to build, portable device and suitable for use in homes, industries, and laboratories. It can help improve safety by providing early warning of harmful gases. This project demonstrates an effective way to monitor air quality using basic electronics and programming.

MQ 135 Gas Sensors, Arduino Uno

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