http://dihour.net/stainless-steel-hand-dryer/power.html

power hand dryers are the more hygienic way to dry your hands compared to traditional push button types. Manual or push button hand dryers can have a bacteria build up on the push button itself whereas these automatic models only require the hands to be placed under the hand dryer to activate the unit. A wide range of automatic units are available from budget units through to high traffic, energy efficient models. Dual Jet Hand Dryer combines high performance with remarkable energy . use of the HEPA filter ensures 430mph of clean sheeted air scrapes water from hands and dries them in under 10 seconds. This built in HEPA filter avoids the hands being dried by air that is dirty and contaminated from the washroom environment as 99.9% of bacteria and viruses are filtered away.