An arrangement includes a processing chamber, at least one cover plate for the processing chamber, and a holding assembly. The holding assembly is arranged to hold the cover plate at an outer surface of the processing chamber. A method for operating such an arrangement is disclosed. The holding arrangement guides the cover plate with respect to the processing chamber from a covering position into an access-enabling position and back from the access-enabling position into the covering position. The cover plate in the covering position covers a part of the outer surface of the processing chamber. The distance between the cover plate in the access-enabling position and the processing chamber occurs. The cover plate is moved from the covering position into the access-enabling position along a curved opening trajectory. This opening trajectory is horizontal or is sloping with respect to the ground.