ligevægtsfugtighedsindhold

Ligevægtsfugtighedsindhold, often abbreviated as EMC (Equilibrium Moisture Content), refers to the moisture content a material will reach when it is in equilibrium with the surrounding environment. This means that the rate of moisture entering the material from the air is equal to the rate of moisture leaving the material into the air.

The EMC of a material is primarily determined by the relative humidity (RH) of the surrounding air and, to a lesser extent, the temperature. At a given relative humidity, a hygroscopic material will absorb moisture from the air if its current moisture content is lower than the EMC, and it will release moisture if its current moisture content is higher. Eventually, the material's moisture content will stabilize at the EMC.

Different materials have different EMC values at the same relative humidity. For example, wood will have a different EMC than concrete or textiles. This property is crucial in many applications. In construction, understanding the EMC of building materials helps predict moisture-related issues like mold growth or material degradation. In the storage and handling of goods, knowing the EMC is essential for preventing spoilage or damage due to excessive or insufficient moisture.

The concept of EMC is also important in fields like agriculture and food science, where the shelf life and quality of products are directly influenced by their moisture content and interaction with atmospheric humidity. Measuring or calculating EMC allows for better control over storage conditions and product stability.