Relative Humidity (RH) is expressed as what?

• A. A ratio of pressure to temperature
• B. A percentage of total water vapor capacity
• C. A measure of air temperature
• D. A fixed quantity of water vapor

Answer: (B)

Relative Humidity (RH) is expressed as a percentage of the total water vapor capacity of the air at a specific temperature. This percentage indicates how much moisture is currently present in the air compared to the maximum amount of moisture that the air can hold at that temperature. When the relative humidity is 100%, the air is fully saturated with water vapor and cannot hold any more, leading to the possibility of precipitation or condensation.

Understanding RH is crucial in many fields, including surgical environments, where maintaining appropriate humidity levels is essential to prevent infection and ensure the safety and efficacy of surgical procedures. High or low levels of humidity can affect the behavior of various instruments and materials used in surgery.