Abstract: An air quality monitor apparatus for use in a ducted system. The apparatus comprising an enclosure having at least one air exchange port, at least one optical system and a plurality of sensors. The air exchange port creates an air stream pathway through the enclosure, while the optical system provides light across the air stream pathways. The plurality of sensors has access to the air stream pathway are configured to measure air quality data of the air stream. At least one microcontroller is configured to process the measured air quality data. At least one communication system is configured to communicate the processed air quality data with an outside network.