The concentration of CO2 in the air is measured in parts per million (ppm). The CO2 concentration outdoors is approx. 350 ppm on average. A level of above approx. 800 ppm negatively impacts on our well-being. The concentration of CO2 in a room depends on the number of people in the room, the length of time that they spend in that room and the air exchange rate. For example, a 60 m³ room that contains two people and has an air exchange rate of 1 will reach a CO2 concentration of 900 ppm. Without ventilation, the concentration of CO2 in the room would increase to 1,500 ppm after two hours and 2,500 ppm after five hours.In order to measure air quality, SENSOAIR type wave uses two sensors to detect the carbon dioxide (CO2) concentration in closed rooms. The quality of the air that has been measured is indicated using a LED light and is transmitted via Z-Wave.