Abstract: The present invention relates to gas evaporator devices (1) and methods for operating them. By virtue of the improvements according to the invention, the service life of conventional gas evaporator devices can be significantly improved, such that the maintenance and material outlay and hence the costs of the coating method are reduced. This is achieved by virtue of the fact that a shielding element (5) impermeable at least to passage of the material is provided at least between the mixture of gas and material flowing in the section (4), in which material to be evaporated is guided in a gas flow and is heated by the heating element (2), and the heating element (2).