Abstract: Systems and methods herein provide low power non-dispersive infrared (NDIR) gas sensors. The gas sensors comprise a thin film plasmonic light source that produces a time modulated parallel light beam at multiple selected wavelengths. The parallel light beam from the light source passes through a gas chamber without using focusing or collimating optical components. The gas sensors are continuously self-calibrated against environmental changes, such as temperatures and relative humidity, and aging. The gas sensors are suitable for use in hazardous environments because their low power and small thermal mass reduces the risk of explosion. The gas sensors can be integrated into conventional mobile device platforms.

Abstract: A valve assembly capable of converting a small leak of a device into a measurable, relatively larger or “burst” flow event is described. In certain embodiments, the valve assembly includes a compliant chamber and, following pressurization of the device, permits flow when the pressure in the compliant chamber drops to a configured fill pressure and restricts (or prevents) flow when the pressure in the compliant chamber increases to a shut-off pressure. The disclosed valve assemblies may be incorporated into a leak detection assembly capable of transmitting usage and/or alarm data to a central service.