A duct section (20, 20", 20′′′, 21, 21′′′, 22, 63, 64) configured for connecting to one or more other duct sections (20, 20", 20′′′, 21, 21′′′, 22, 63, 64) for creating a duct system for delivering and/or removing gaseous substances, wherein the duct section (20, 20", 20′′′, 21, 21′′′, 22, 63, 64) comprises a circumferential outer wall (23, 411, 412, 511, 512) with an inner surface and an outer surface, wherein the duct section (20, 20", 20′′′, 21, 21′′′, 22, 63, 64) is a double wall duct section or a double wall concentric duct section, comprising a circumferential inner wall (24, 45, 56, 65) that is enclosed by and spaced apart from the circumferential outer wall (23, 411, 412, 511, 512), wherein the duct section (20, 20", 20′′′, 21, 21', 21′′′, 22, 63, 64) comprises a first end with a male end portion configured to fit in a female end portion of one of the one or more other duct sections (20, 20", 20′′′, 21, 21′′′, 22, 63, 64), characterized in that the male end portion comprises an opening (29, 67, 341, 531) in a circumferential wall of the male end portion, wherein said opening (29, 67, 531) is spaced a first distance apart from the first end, wherein the male end portion comprises a protruding member (27, 27', 27", 42, 52, 61, 61') that is arranged to pass through the opening (29, 67, 531) in the male end portion projecting outwards with respect to the outer surface of the outer wall (23, 411, 412, 511, 512) and, when interconnected with said one of the one or more other duct sections (20, 20", 20′′′, 21, 21', 21′′′, 22, 63, 64), passes through a receiving opening (28, 28', 28", 532, 62) in a circumferential wall of the female end portion, wherein said protruding member (27, 27', 27'', 42, 52, 61, 61') is supported by a resilient member (44, 54, 66) which is arranged inside the duct section (20, 20", 20′′′, 21, 21′′′, 22, 63, 64). wherein the duct section (20, 20", 20′′′, 21, 21′′′, 22, 63, 64) is a double wall duct section or a double wall concentric duct section, comprising a circumferential inner wall (24, 45, 56, 65) that is enclosed by and spaced apart from the circumferential outer wall (23, 411, 412, 511, 512), wherein the duct section (20, 20", 20′′′, 21, 21', 21′′′, 22, 63, 64) comprises a first end with a male end portion configured to fit in a female end portion of one of the one or more other duct sections (20, 20", 20′′′, 21, 21′′′, 22, 63, 64), characterized in that the male end portion comprises an opening (29, 67, 341, 531) in a circumferential wall of the male end portion, wherein said opening (29, 67, 531) is spaced a first distance apart from the first end, wherein the male end portion comprises a protruding member (27, 27', 27", 42, 52, 61, 61') that is arranged to pass through the opening (29, 67, 531) in the male end portion projecting outwards with respect to the outer surface of the outer wall (23, 411, 412, 511, 512) and, when interconnected with said one of the one or more other duct sections (20, 20", 20′′′, 21, 21', 21′′′, 22, 63, 64), passes through a receiving opening (28, 28', 28", 532, 62) in a circumferential wall of the female end portion, wherein said protruding member (27, 27', 27'', 42, 52, 61, 61') is supported by a resilient member (44, 54, 66) which is arranged inside the duct section (20, 20", 20′′′, 21, 21′′′, 22, 63, 64).