NDIR IR Gas Sensor for CO2

NDIR IR Gas Sensor for CO2 measure carbon dioxide concentration through absorption of infrared light at 4.26 µm — the characteristic molecular absorption wavelength of CO2. They project IR light from a broadband source through the sample gas volume inside a measurement cell. The photodetector measures intensity reduction at this wavelength. The sensor converts this attenuation directly to a ppm or volume percent concentration reading. Furthermore, this principle is continuous, non-consumptive, and highly stable — avoiding the drift, poisoning, and humidity sensitivity that limit electrochemical and metal oxide CO2 sensors.

Dual-wavelength reference designs add a second detector at a wavelength CO2 does not absorb. The ratio between sample and reference channel signals cancels source aging, temperature variation, and optical cell fouling. As a result, these sensors maintain calibration accuracy across 5 to 10 year service intervals. This reduces recalibration frequency and maintenance costs across large multi-point installations significantly.

OEM CO2 NDIR modules cover a wide performance range. The Senseair S8 measures 0 to 40,000 ppm at ±40 ppm accuracy from a 57×35×14mm housing at under 35mW. The Sensirion SCD41 adds on-chip humidity and temperature compensation from a 2.7V supply — integrating into IoT air quality monitors and HVAC demand ventilation controllers. Additionally, industrial NDIR CO2 sensor heads output 4–20mA analog and Modbus RTU signals for direct PLC and SCADA integration. They activate ventilation fans and alarm systems automatically when CO2 exceeds pre-set threshold values.

Clinical capnography NDIR CO2 sensors respond in under 100 milliseconds. This captures the full exhaled CO2 waveform during mechanical ventilation in ICU and operating theatre environments. Moreover, sidestream capnography modules draw 50 to 200 ml/min sample flow through desiccant-protected cells — removing breath moisture before CO2 measurement to prevent condensation errors.

These sensors serve Pakistan’s CMH and teaching hospital ventilator systems, commercial building HVAC installations in Karachi and Lahore, greenhouse cultivation facilities in Punjab, pharmaceutical fermentation monitoring programs, and university environmental research departments requiring accurate, continuous CO2 measurement across clinical, industrial, and environmental applications.

Tactical Supply Pakistan supplies NDIR infrared CO2 gas sensors for clinical capnography, HVAC control, industrial process monitoring, and environmental CO2 measurement procurement across Pakistan.