A gas sensor system includes a sensing tube having an outer surface, and an inner surface defining a passage. A plurality of openings is formed through the outer surface and the inner surface. Each of the plurality of openings being no greater than 0.5 millimeters (mm) in diameter. A hydrophobic sealant layer covers the sensing tube. A protective layer covers the hydrophobic sealant layer. A sensor node is arranged along the sensing tube. The sensor node includes an inlet, an outlet, and an interior chamber arranged between the inlet and the outlet. A sensor element is arranged in the sensor node. The sensor element includes a first end and a second end. A sensor cable extends along the sensing tube. The sensor cable includes a first section connected to the first end of the sensor element and a second section connected to the second end of the sensor element.