NDIR Methane Sensor

NDIR methane sensors measure CH4 concentration through infrared light absorption at the 3.3 µm C-H stretch molecular absorption band. 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 to a ppm or %LEL concentration reading. Furthermore, this principle avoids catalytic poisoning — a common failure mode in pellistor sensors exposed to silicone, halogen, lead, and sulfur compounds in gas processing environments.

Dual-wavelength reference designs add a second detector at a non-absorbing wavelength. The ratio between sample and reference signals cancels source aging, temperature drift, and optical cell fouling. As a result, NDIR methane sensors maintain calibration accuracy across 5 to 10 year service intervals. This significantly reduces recalibration frequency and replacement costs across large fixed detector installations.

OEM NDIR methane modules integrate into fixed detector heads, portable gas analyzers, and process instruments. Output interfaces include 4–20mA analog, Modbus RTU, HART, and UART digital protocols. Fixed-point industrial detector heads mount on standard pipe stands in compressor rooms, valve stations, and gas turbine enclosures. They activate alarm relay contacts and safety system inputs when CH4 crosses pre-set %LEL thresholds. Additionally, ATEX and IECEx Zone 1 certified housings in stainless steel meet the hazardous area installation requirements of Pakistan’s oil and gas processing facilities.

Open-path NDIR methane sensor pairs project IR beams across 5 to 200 meters. They detect diffuse methane cloud releases across large open process areas that fixed-point sensors cannot cover. Moreover, portable handheld NDIR methane sensors deliver ppm-level readings for confined space pre-entry checks, pipeline leak surveys, and compliance monitoring without fixed infrastructure.

These sensors serve Pakistan’s SSGC and SNGPL gas distribution networks, OGDCL and PPL processing facilities in Sindh and Balochistan, WAPDA gas turbine stations, LPG storage operators, and fertilizer plants in Multan and Lahore requiring accurate, long-life CH4 detection across fixed area monitoring and portable field survey applications.

Tactical Supply Pakistan supplies NDIR methane sensors for pipeline safety monitoring, industrial hazardous area detection, and gas facility leak survey procurement across Pakistan.