The invention relates to a channel system for leak detection and/or for building up a barrier gas layer, for a conduit component, such as a pipe, a control valve, a ball valve, a throttle valve, a linear or pivoting valve, a pig unit or the like, a process-engineering apparatus, in particular for processing corrosion-prone media, such as liquid chlorine gas, a cryogenic medium, etc. The channel system is to be formed between an inner face of the conduit component substantially conveying the process stream of the process medium and a liner lining the inner face, in particular a plastic lining, and extends from or at least over a damage-prone point of the liner to at least one detection outlet of the conduit component and/or an at least one detection cavity within the conduit component which is accessible from the outside of the conduit component in such a way that a continuous fluid connection of the damage-prone point via the at least one detection outlet and/or the at least one detection cavity is formed.