The invention relates to a radiation appliance (21) and a powder-application station (4), an arrangement thereof for powder-coating temperature-sensitive materials, such as timber-derived products and MDF panels (8), and an associated method. The inventive arrangement and method are characterised in that the specific geometry of the radiation appliance (21) or the corresponding mode of operation enables a short but sufficient homogeneous radiation action over the surface of the substrate (8) to be coated, without the core temperature of the substrate exceeding a critical value. Said arrangement comprises a grinding station (1), a flame-treatment station (2), a spray station (3), a powder-application station (4), a radiation appliance (5), and a curing/crosslinking region (6) that can preferably be continuously passed through. The inventive radiation appliance (21) is characterised in that the radiating elements are displaceably arranged in an annular or circular manner, while the powder-application station (4) is provided with diverting elements which are used to smooth the electrical field on the surface of the substrates and thus prevent concentrations of powder on edges and the like.