The moisture content of all materials tries to reach an equilibrium with the relative humidity in ambient air

物質中的水份總是試圖與環境的相對濕度達到平衡

At equilibrium the relative humidity of the material is called equilibrium relative humidity ERH

物質中的濕度達到平衡后稱為平衡相對濕度

Equilibrium relative humidity divided by 100

平衡相對濕度除以 100 A w = ERH / 100

Application

應用 : moisture in oil 油中微量水份