Sanatorium is a specialized medical facility typically focused on long-term treatment, often in a healthy climate, historically used most commonly for tuberculosis treatment and convalescence. In a modern context, especially in Poland, patients can be placed on a waiting list (kolejka oczekujących) for treatment at a sanatorium financed by the National Health Fund (NFZ). To check one's place or number in this queue, patients use an online tool on the NFZ website where they input their referral number (numer skierowania) and date of birth to see their waiting position. The average waiting time is currently around 10 months but varies by region. Thus, the "numer" in context means the patient's position in the waiting queue to receive treatment at the sanatorium.