An electrochemical gas sensor (100, 200, 300) comprising: a housing (202, 204) including: a gas sensor cap, a gas inlet capillary defined as a channel that passes through the gas sensor cap, an electrolyte, a sensing electrode, and a counter electrode (228, 700) configured to generate a gas during use of the electrochemical gas sensor (100, 200, 300), wherein a portion of the housing (202, 204) comprises an aperture through at least one surface of the housing (202, 204), the aperture dimensioned and configured to prevent water ingress to the electrochemical gas sensor (100, 200, 300) and allow gas egress from the electrochemical gas sensor (100, 200, 300); a plurality of solid features molded within at least one surface of the gas sensor cap, the plurality of solid features configured and dimensioned to form support pillars about a vent membrane so as to prevent deformation of the vent membrane during assembly and use of the electrochemical gas sensor (100, 200, 300) with the gas sensor cap; a vent assembly adapted to release at least a portion of the gas generated at the counter electrode (228, 700) out of the electrochemical gas sensor (100, 200, 300); wherein the vent assembly includes the vent membrane that is adapted to be heat sealed at a portion of the gas sensor cap and wherein the plurality of solid features defines a cavity between an internal surface of the plurality of pillar shaped moldings and a portion of the vent membrane, and wherein the cavity is operable to accumulate at least a portion of the gas released out through the vent membrane before the at least a portion of the gas, eventually vents out through a vent conduit that is in fluid communication with the vent membrane. a gas sensor cap, a gas inlet capillary defined as a channel that passes through the gas sensor cap, an electrolyte, a sensing electrode, and a counter electrode (228, 700) configured to generate a gas during use of the electrochemical gas sensor (100, 200, 300), wherein a portion of the housing (202, 204) comprises an aperture through at least one surface of the housing (202, 204), the aperture dimensioned and configured to prevent water ingress to the electrochemical gas sensor (100, 200, 300) and allow gas egress from the electrochemical gas sensor (100, 200, 300); a plurality of solid features molded within at least one surface of the gas sensor cap, the plurality of solid features configured and dimensioned to form support pillars about a vent membrane so as to prevent deformation of the vent membrane during assembly and use of the electrochemical gas sensor (100, 200, 300) with the gas sensor cap; a vent assembly adapted to release at least a portion of the gas generated at the counter electrode (228, 700) out of the electrochemical gas sensor (100, 200, 300); wherein the vent assembly includes the vent membrane that is adapted to be heat sealed at a portion of the gas sensor cap and wherein the plurality of solid features defines a cavity between an internal surface of the plurality of pillar shaped moldings and a portion of the vent membrane, and wherein the cavity is operable to accumulate at least a portion of the gas released out through the vent membrane before the at least a portion of the gas, eventually vents out through a vent conduit that is in fluid communication with the vent membrane.