Which measure best minimizes microbial growth in the operating room?

• A. Increasing humidity to 70-90% is recommended to minimize microbial growth.
• B. Maintaining proper humidity and temperature minimizes microbial growth.
• C. Keeping humidity very low below 10% is ideal for microbial control.
• D. Allowing uncontrolled environmental conditions helps staff comfort.

Answer: (B)

Controlling the operating room environment to limit microbial growth relies on keeping humidity and temperature within stable, appropriate ranges. Microorganisms thrive or spread more easily when conditions are too moist, too dry, or unstable, so a well-regulated humidity level combined with a consistent temperature reduces microbial survival on surfaces and in the air, helps prevent condensation, and supports effective filtration and airflow. This balanced approach is safer and more effective than making the room very humid (which promotes mold and bacterial growth), making the air excessively dry (which doesn’t reliably reduce microbes and can cause other problems), or leaving environmental conditions uncontrolled (which increases risk to patients and staff).