Noise
A hand dryer, whether in an office, restaurant, or school can create a lot of noise that can be disturbing to people in the area. Traditional hand dryers typically generate between 85-100Db of noise (about the same as a loud alarm or a truck passing close by), so even with the bathroom doors closed, that sound can pass into the surrounding area.
Quiet hand dryers are an effective solution to the noise problem, but in some cases, the design choices made to reduce the amount of noise produced can make the dryer less effective in its primary function and take longer to dry the user’s hands.