What does relative humidity indicate?

Relative humidity is a critical concept in understanding atmospheric conditions, particularly in building maintenance and indoor air quality. It quantifies the amount of moisture present in the air relative to the maximum amount of moisture that the air can hold at a specific temperature. This means that relative humidity not only indicates the moisture level but also considers the temperature, which affects the air's capacity to hold water vapor.

For example, when the relative humidity is at 50%, this means the air is holding half of the moisture it is capable of retaining at that temperature. This measurement helps in assessing comfort levels, moisture-related issues, and the potential for mold growth within buildings. Understanding relative humidity is essential for maintaining a healthy indoor environment, as it impacts both physical comfort and the integrity of building materials.

Other options do not capture the complete nature of relative humidity. While they may touch on aspects related to humidity or atmospheric conditions, they do not specify the critical relationship between the current moisture level and potential maximum capacity at a given temperature, which is fundamental to understanding relative humidity.