This portable air quality monitor is used for real time measurements of a variety of common air pollutants. Sensors are housed in a separate, easy to change, cartridge allowing the owner to choose which gasses and how many gasses to monitor. Sensors that can be purchased include ammonia, carbon dioxide, carbon monoxide, chlorine, formaldehyde, hydrogen, hydrogen sulfide, methane, nitrogen dioxide, non methane hydrocarbons, ozone, perchloroethylene, PID, sulfur, or VOC.