Operating room HVAC system must maintain safe conditions in the most efficient way possible, according to an article on the FacilityCare website. For peak efficiency, ORs should use occupied/unoccupied ventilation control systems to cut air-conditioning costs during unoccupied hours.
Air coming from outside must be conditioned to maintain a relative humidity range between 30 and 60 percent for proper infection control.
At the lower room temperature set points of ORs, which can sometimes be lower than 60 degrees, humidity control is difficult without extensive dehumidification — and dehumidification is energy intensive, the article said.
ORs require a large quantity of outside air — often with a high moisture content. A desiccant wheel can enhance the ability of an air-handling unit’s cooling coil to dehumidify the air.
Ventilation and Filtering for Infection Control 
ChristianaCare Opens Aston Campus Neighborhood Hospital
Stantec Breaks Ground on New Academic Medical Center in Miami
Building Senior Living for the Next Generation of Retirees
Managing Drain and Biofilm Risk