"Examples of applications for this sensor system include: measuring ratios of O2:N2 in on-site generation systems (membrane, PSA VPSA, etc.); measuring H2O content in dryers or process streams; measuring ratios of O2 to combustible gases such as hydrocarbons or H2 for safety purposes; monitoring the inerting of vessels, tanks and reactor processes; monitoring the ratios of H2:CO in syn-gas processe" . . . .