A medical system and method to operating the medical system is presented. A patient storage element is assigned to a patient comprising identification information identifying the patient. A medical device has a contaminating patient application. A medical device storage element on the medical device comprises use information. A clearing device receives the identification information from the patient storage element and the use information from the medical device storage element and analyzes the use information. If in analyzing the use information it is found that application of the medical device to the patient is allowed, a clearance signal is outputted. If in analyzing the use information it is found that application of the medical device to the patient is not allowed, the identification information is analyzed. If in analyzing the identification information it is found that application of the medical device to the patient is allowed, a clearance signal is outputted.