A gas monitoring apparatus and system that provides for reliable and accurate monitoring of gaseous hydrogen and other compounds in dielectric oil. The first and second radiation paths are operable to provide substantially unfiltered and wavelength dependent filtered radiation transmission therethrough respectively to the detectors. The materials of the carrier and the first dielectric layer are selected to prevent the IC integrated substrate from peeling off the carrier during processing and to allow the IC integrated substrate to naturally separate from the carrier after being cut, through the adhesion between the carrier and the first dielectric layer. One side of each cycle pipe is attached to a foregoing joint in front of the check value and the other side is attached to a rearward joint behind the check value of each main pipe. The wall mounted dead bolt includes an aperture at one end for receiving the dead bolt of the door mounted dead bolt therein.