Abstract: A device for monitoring gas effusing from a pipe, the device comprising a mounting assembly having an upper and lower bracket; a housing located on the upper bracket; the bottom of the housing is of a shape complementary to the pipe being monitored; a probe assembly; a bore in the housing for receiving the probe assembly; the probe assembly comprising: a probe insert; a chamber for collecting gas in the bottom of the probe insert formed by side walls and an upper wall; a compressible sealing means in the bottom of the side walls for sealingly engaging the outer surface of the pipe to be monitored; a passageway in the probe insert, extending from an outlet at the top surface of the probe insert to an inlet in the upper wall of the chamber, such that the passageway is in flow communication with the chamber; a tube receivable through the outlet of the passageway; a plate removably connected to the housing for, securing the probe assembly in place; the plate comprising a biasing means for compressing the sealing