What is the purpose of maintaining positive pressure in the operating room relative to surrounding spaces?

• A. To push air into adjacent spaces when doors open.
• B. To pull contaminants into the room when doors open.
• C. To maintain negative pressure in surrounding spaces.
• D. To help keep contaminants from entering the room by causing air to flow out of the OR when doors open.

Answer: (D)

Maintaining a higher pressure in the operating room than in surrounding spaces keeps air flowing outward when doors are opened. This positive pressure pushes potentially contaminated air from the hallway back into the corridor rather than allowing hallway air to be drawn into the sterile environment, helping protect the patient and surgical team from contaminants. The room is kept overpressure by supplying more air (and filtration) than is exhausted, creating a continued outward flow. The other options describe inward airflow or negative pressure, which would not prevent contaminants from entering the OR.