IOT Based: Air Quality Monitoring System

Airpollutionhasemergedasacriticalglobalconcern,posing seriousthreatsto humanhealth, climate stability and ecological balance. Conventional air quality monitoring stations are often expensive, stationary, andlimitedincoverage, restricting theirabilitytoprovidereal-timelocalizeddata.Toaddressthis challenge, this study presents the design and development of an Internet of Things (IoT)-based Air Quality Monitoring System utilizing low-cost sensors and wireless communication. The proposed system employs the MQ135 sensor to detect harmful gases, such as carbon dioxide, ammonia, and nitrogen oxides, whereas the DHT11 sensor is used to monitor ambient temperature and humidity levels. The collected data were processed usingan ESP8266microcontroller,whichenabledreal-timewirelesstransmissionandvisualizationonanLCD display through an I2C interface. The modular design ensures portability, scalability, and energy efficiency, making it suitable for smart-city applications. The experimental results demonstrate the feasibility of the proposedsystemindeliveringaccurate andtimely airquality dataatasignificantly reducedcostcomparedwith traditional monitoring infrastructure. This study contributes to the advancement of low-cost environmentalmonitoringsolutions,enablingimprovedpublicawarenessanddata-drivendecisionmakingforpollution control.