Close-proximity monitoring solution

Why photoacoustics delivers where others fall short

At Sensirion Connected Solutions, we build on more than 25 years of deep sensor expertise of our mother company, Sensirion AG—a global leader in advanced sensor technologies and one of the world’s top suppliers of thermal conductivity (TC) sensors for applications such as refrigerant leakage detection. This profound understanding of TC sensing has uniquely positioned us to innovate beyond its limitations.

Our proprietary photoacoustic spectroscopy technology represents the next evolution in gas sensing. While close-proximity solutions based on TC technology typically detect methane concentrations down to 50 ppm and only so under very ideal environmental conditions, our photoacoustic sensors beat this by at least a factor 5 delivering methane-specific accuracy down to 0.5 ppm (Nubo Sphere) and 10 ppm (Nubo Sentry). With 99% methane selectivity and negligible cross-sensitivities, in contrast to TC sensors, they detect even short-lived emission peaks independent of the actual gas composition with precision and speed.

Did you know that different gases in natural gas emissions have different thermal conductivities, meaning they carry heat differently? Methane has a higher thermal conductivity than air at room temperature—it transfers heat more easily. But gases like ethane and propane do the opposite, with lower thermal conductivity than air. When these gases mix, their heat-carrying effects can cancel each other out, making it harder to detect them using temperature-based sensing methods. A potential risk that Sensirion was not willing to take.