Carbon dioxide is a gas that is odorless, non-irritating to the skin, and difficult to detect by the human body. Carbon dioxide can be seen everywhere in life, but carbon dioxide is also very harmful to the human body. When the concentration of carbon dioxide in the air is too high, it will make People's mental power is not concentrated, headache, dizziness, drowsiness, etc., higher will make it difficult to breathe, or even death from poisoning. The carbon dioxide detector is used in carbon dioxide gas concentration detection and carbon dioxide concentration exceeds the standard reminder, can accurately detect the concentration of carbon dioxide and in the display of real-time concentration value, standard signal output, with signal stability, sensitivity and high precision suitable for various places.