... three-color backlit LCD indicates and alarm different air quality levels: GREEN-for optimal air quality, YELLOW-for moderate air ... Carbon dioxide (CO2), CO2 average level (in setting time range: 1~24hous), Temperature, Humidity, Clock and Time. DPM1004: Carbon dioxide ( ... CO2), CO2 average level (in setting time range: 1~24hous), VOC, Temperature, Humidity, Clock and Time. n Monitoring ...