Alphasense IRC-A1
A compact Alphasense NDIR carbon-dioxide sensing cell for OEM instruments spanning indoor air quality, safety, combustion and process measurement.
Key Specifications
Product Positioning
Alphasense positions IRC-A1 for OEM instruments that require selective CO₂ measurement across ppm and percent-volume ranges. Range-specific performance values should be selected according to the intended IAQ, safety, combustion or process application.
Official Resources
This page uses current Alphasense manufacturer specifications.
View Official Alphasense Product PageAirAlign is independent of Alphasense and AMETEK. Manufacturer documentation remains authoritative.
Alphasense IRC-A1 — pyroelectric dual-channel NDIR and calibration linearisation — detailed technical comparison and documentation
Manufacturer source data are specific to the selected sensor physics, ordered range and application conditions. Factory product family options do not all apply to a single device.
| Specification | Original maker evidence | Integration/selection qualification |
|---|---|---|
| Sensing element | A-Series dual-channel pyroelectric NDIR CO₂ detector | A raw sensor optical/electrical assembly, not a 4–20mA Modbus ready transmitter. |
| Range options | IAQ 0–5,000ppm; Safety 0–5%vol; Combustion 0–20%vol; Process 0–100%vol | The installed spectral calibration linearisation constants and accuracy depend on ordered CO₂ grade. |
| Accuracy group | IAQ ±1% full scale, Safety ±1.5% FS, Combustion ±2.5%FS, Process ±4%FS in original OEM table | Percent full scale can be a large absolute error close to zero; do not describe it as percent of reading. |
| Response | T90 <40 seconds at 20°C, maker reference | Installed sample flow/ambient filter changes response. |
| Onboard compensation | Thermistor output supports temperature compensation and dual-channel optical reference | A host electronics transfer circuit and calibration remain required. |
| Original OEM app note | AAN 201-06 publishes separate IRC-A1 IAQ/Safety/Combustion/Industrial linearisation and compensation coefficients | Do not copy coefficients from thermopile IRC-AT or between sensor ranges. |
| Optical environmental issue | Original maker notes optional IRC-AF external-light filter when ambient light reaches dust-filter surface | Uncontrolled illumination of a sensor window may affect readings even with onboard compensation. |
Design, gas calibration and safety boundaries
For 0–5000ppm IAQ, Alphasense’s original technical material discusses calibration with a 4000ppm reference and normalized linearisation; those steps should be performed by the OEM instrument builder, not assumed pre-solved by the raw A-Series element. Select a certified front end/analogue acquisition that matches the pyroelectric architecture and temperature-compensation coefficients. Manufacturer’s 2022 application note distinguishes IRC-A1 from IRC-AT: copying universal ‘b/c’ coefficients between models can materially bias an apparently precise ppm signal. A part intended for safety instrument development does not itself grant final fixed-detection instrument Ex approval.
Primary manufacturer technical reference: Official exact model and current product documentation. Obtain the current order code, calibration datasheet and any region-specific approval before installation.
AirAlign source-backed product engineering notes · 25 October 2026. Neither an independent calibration certificate nor finished gas detector Ex/SIL approval.