IS-Instruments has published test results showing its Notus gas Raman spectrometer can measure methane, carbon dioxide, ethylene, and carbon monoxide at concentrations as low as 5 ppm using a single instrument with no reconfiguration between measurements. The company reports signal-to-noise ratios above 60 for methane at 10 ppm and estimates detection limits in the hundreds of ppb for methane and ethylene with the current setup. Carbon monoxide was measured at 5 ppm with an estimated detection limit around 1 ppm. The multi-gas capability is relevant for emissions monitoring and industrial gas analysis, where operators often need to track several gases at once without installing separate analyzers. The tests also highlight a practical bottleneck: at very low concentrations, the limiting factor is not the instrument itself but the availability of certified reference gas mixtures with tight enough tolerances to verify performance. Notus is now undergoing independent testing ahead of a full market launch.
