The amount of time taken to dry your hands with a hand dryer is dependent on the method used to dry the skin and the amount of power used. This can have a significant impact on how much energy you use, and how congested bathrooms can become.
With a low-cost evaporative hand dryer, it might take more than 30 seconds for the user to dry their hands properly. This is because of the way the dryer works. Air is heated and blown slowly over the skin as the hands are rubbed together. By spreading the moisture into a thin layer on the skin, it makes it evaporate away more quickly, but you are still reliant on changing the state of the water, and this slows down the process.
Jet hand dryers are simpler in that they use the fast-moving air from their nozzles to blow the water droplets off the skin without needing to heat them up. Users simply move their hands through the stream of air. Running in eco mode, a Mitsubishi Electric Wave u02 hand dryer takes between 14 and 16 seconds to fully dry the user’s hands.
The secondary factor in the time taken to dry hands is the amount of power used. A more powerful heating element can speed up the process of evaporating moisture from the hands – although there is a limit to this because air that is too hot could cause discomfort and even injury. Setting the motor in a jet hand dryer causes an increase in the speed of the air flow which will generate more force to push the water away. At full power mode the time taken to dry hands without using a heater can be reduced to 11 seconds.
