A respiratory or respiration hose is made of a transparent or translucent material, e.g. a silicon caoutchouc, the hose has a helical, preferably hollow ridge or bar on its outer surface bonded thereto by a silicon based adhesive; heating conductors means are arranged on a foot portion of the ridge, on one or both sides of the foot portion of the ridge and are adhesively bonded to the hose; a return conductor may run through the hollow ridge interior; heating current is fed to the heating conductor which is provided in parallel or serial connection.