Automatic Vehicle Emission Monitoring and Alert System Using Arduino and MQ135 Sensor

Emission checking is essential to reducing air pollution in urban areas. Conventional systems, such as Pollution Under Control (PUC) registration in India, rely on manual inspections without real-time automation. This has led to vehicles with unchecked emissions operating without proper regulation, thereby worsening air quality issues. The proposed system employs an MQ135 sensor and an Arduino-based mechanism to monitor vehicle emissions at petrol stations. When pollutant levels exceed a predefined threshold, an audio alert is triggered, prompting the vehicle owner to take immediate action. By integrating emission checks into routine refueling, the system eliminates the need for separate emission inspections. This approach can help enforce stricter emission standards, reduce pollutant levels, and improve air quality in high-traffic areas.