The wet-bulb temperature is measured using a thermometer whose bulb is wrapped in a water-saturated cloth (called a wick). It reflects the cooling effect of evaporation. It is always lower than or equal to the dry-bulb temperature and it indicates the humidity level: the more moisture in the air, the closer WBT is to DBT. Wet-bulb temperature is important in kiln drying, as it helps determine how fast timber can safely lose moisture