Infrared Sensor Technology and its Impact on HVAC CO2 Measurement Accuracy

As energy-efficiency regulations become stricter, so do the requirements for CO2 sensors. One of the forerunners in improving indoor air quality is the State of California. Its Building Standards Code sets performance criteria for CO2 sensors: “CO2 sensors shall be certified by the manufacturer to be accurate within plus or minus 75 ppm at a 600 and 1000 ppm concentration when measured at sea level and 25°C, factory calibrated or calibrated at start-up, and certified by the manufacturer to require calibration no more frequently than once every 5 years.” This indicates the importance of carefully examining specifications when choosing a sensor – not all sensors will perform in line with expectations.