Operating Rooms consume a great deal of energy, considering the high airflow requirements needed, bright lighting, and significant plug load from patient care equipment. There are, however, strategies to conserve energy and still meet the stringent safety requirements of maintaining positive room pressure. Two conditions need to be met to enable OR energy savings. The first is a method to trigger occupied and unoccupied states. And the second is to act on that state change to setback both temperature and airflow.
Occupancy state is usually achieved with one or more sensors, or trigger conditions such as “lights on.” Simple passive infrared occupancy sensors alone can cause false events due to staff entering the room for supplies, pass through, or cleaning. A combination of sensors, trigger conditions, and scheduling is most effective in driving a true occupancy state for an OR. Unoccupied states can be accomplished via timeout conditions, no sensed activity, and/or scheduling.
Once an unoccupied state is established, temperature and airflow can be rolled back, but only within the limits of state or ASHRAE Standard 170 codes. OR airflow can be reduced from 20 air changes per hour (ACH) to 4 ACH in most cases, provided the room remains under positive pressure of at least 0.01” WC. A more practical goal of 8 ACH will achieve significant energy savings at less risk of loss of room pressure. Studies have shown that northern US climate ORs can save $2,500 to $4,000 per OR per year with this type of setback strategy.
The most efficient way to measure, monitor, and alarm on OR environmental conditions is using a monitor that can support pressure, temperature, and humidity, like the Setra SRCM.
CLICK HERE to learn more about Setra's full line of pressure monitors.