The CO₂ transmitter shall be microprocessor based suitable for measuring CO₂ concentration upto 2000 ppm, in the air. It shall use Non-dispersive Infa-red (NDIR) sensing technology with Automatic Baseline Calibration (ABC). Gas sampling shall be by passive diffusion with no moving parts.

It shall have a warm-up time of less than 1 minute and the sensor life expectancy shall be more than 15 years. In normal IAQ applications, the transmitter shall require no maintenance. The transmitter shall have an accuracy of + 1% of measurement range or + 5% of measured value.

The transmitter output shall be 0-10 VDC or 4-20 mA.