The BAPI CO2 Sensor is an accurate and reliable way of incorporating demand controlled ventilation into a building's HVAC strategy. The Dual Channel "24/7" unit has been optimized for continuously occupied areas and features a three-point calibration process for enhanced stability, accuracy and reliability. It includes a built-in Barometric pressure sensor that continuously compensates the output for accurate readings despite the weather or altitude of the installation. The BAPI-Stat "Quantum Prime" Unit Without Display comes as a CO2, temperature and humidity sensor. The CO2 level is indicated as "Good, Fair or Poor" by three discrete green, yellow and red LEDs on the front of the unit.