<![CDATA[ Air pollution monitoring in urban areas requires portable and real-time solutions to overcome the limitations of fixed monitoring stations. This study aims to design and develop a mobile carbon monoxide (CO) monitoring device to support urban air quality mapping. The proposed system integrates Internet of Things (IoT) technology, including the MiCS-4514 gas sensor, ESP32 microcontroller, Bluetooth, and Wi-Fi communication. Data transmission is conducted through the MQTT protocol to the Antares cloud platform. To ensure consistent measurement in motion, the device is equipped with a protective air chamber, DC pump, and flowmeter with a constant airflow of 1 liter per minute. Sensor calibration using the span gas method achieved a relative standard deviation of 1.58%, within the acceptable threshold and confirming valid precision. Field testing was conducted in two scenarios: static (indoor and outdoor) and mobile. Static tests demonstrated that sensor performance is highly influenced by wind direction and proximity to emission sources. Mobile tests were performed across three routes in Bandung City, covering a total of approximately 24 km during morning, midday, and evening periods. The average CO concentrations recorded were 3.76 ppm, 2.90 ppm, and 3.93 ppm, respectively. The highest detection rate, 7.8%, occurred during midday monitoring. The developed device successfully detected spatial CO distribution in real-time under dynamic conditions. This research contributes to the development of adaptive and efficient mobile air quality monitoring technologies, supporting data-driven environmental decision-making and potential integration with smart city systems.]]>
