RHnivået

RHnivået, or relative humidity level, is a measure of the amount of water vapour in the air relative to the maximum amount the air can hold at a given temperature. It is expressed as a percentage. When air contains as much water vapour as possible at the current temperature, RHnivået is 100 percent. Because the capacity of air to hold moisture increases with temperature, RHnivået depends on both moisture content and temperature.

Measuring RHnivået is done with instruments such as hygrometers, psychrometers, dew point sensors, or data loggers. Readings are typically reported as a percentage and can be taken indoors or outdoors. Since air temperature affects what percentage is possible, RHnivået is often discussed together with temperature and dew point in meteorological or building-management contexts.

RHnivået has important implications for comfort, health, and the behavior of materials. Low levels (often below about 30%) can cause dry skin, irritated eyes, and static electricity; high levels (above roughly 60–70%) can promote mold growth, condensation, musty odors, and warping of wood. Indoor guidelines commonly recommend maintaining RHnivået roughly between 30% and 50% for comfort, with some climates allowing up to 60%.

Seasonal and environmental factors influence RHnivået. Outdoor climate, heating, cooling, and ventilation determine indoor moisture levels. In winter, heating can lower indoor RHnivået, while in summer high outdoor humidity can raise it if not controlled. RHnivået is routinely monitored in homes, offices, museums, warehouses, and agricultural settings to protect health, comfort, and sensitive materials.