HUMIDIFIER

A humidifier having a multiplicity of metallic flow plates and a multiplicity of water transfer membranes, in particular for humidifying process gas for an electrochemical system or for HVAC applications is described. The humidifier has a construction in which the metallic flow plates and the water transfer membranes are arranged such that in each case at most one of the single-layer flow plates is arranged between adjacent water transfer membranes of the stack; and at least one of the water transfer membranes is in each case accommodated in a sealing manner, in particular clamped in a sealing manner, between the mutually facing sealing lines of adjacent flow plates of the stack. The humidifier has lower production costs, greater efficiency and lower weight.