PROBLEM TO BE SOLVED: To make it possible to provide a constantly comfortable temperature environment for both of a patient and an operator during an operation.SOLUTION: A patient air outlet 10 for expelling warm air to a patient 6 is provided on a ceiling surface 3 directly over an operating table 5. Operator air outlets 11 for expelling cool air to operators 7 are provided on both sides of the patient air outlet 10. Aperture area of each operator air outlet 11 is set to be smaller than that of the patient air outlet 10. Expelled speed of cooling air expelled from each operator outlet 11 is made to be higher than that of warm air expelled from the patient outlet 10.SELECTED DRAWING: Figure 1
