In the field of medical devices, for instance patient tables, it is known to block the movement of moveable components of a respective apparatus using blocking means and to release these only after actuating a switch. To be able to dispense with the foot switch, an authorized operator is equipped with a radio frequency identification tag and interrogation means for interrogating the radio frequency identification tag are provided on the apparatus. Once the operator initiates a movement by exerting a force, a sensor detects this force and activates the interrogation means. If the interrogation means identify that the radio frequency identification tag is sufficiently close thereto, it is concluded that the authorized operator would like to initiate the movement and the moveable part is released.
