Electric hand dryers are often chosen as a direct replacement for paper towels to avoid the costs associated with procuring, storing, checking, refilling and disposing of paper towels and to avoid unsightly wet towels that may end up on the washroom floor. They produce a high speed flow of heated air which has a drying action due to a combination of pressure forces and evaporation. The effectiveness of a hand dryer is ultimately determined by the speed of the fan generating the flow of air (usually measured in rpm) and the power of the heating element (usually measured in kW). These are the key parameters with which to evaluate hand dryer, the larger the combination of these figures the shorter the drying time. Casing material is generally determined by the installation.
- Plastic is a cost effective solution suitable for low traffic environments where the risk of vandalism is low, such as small offices.
- Enamelled steel is a good general purpose solution suitable for mainstream applications such as railway stations and shopping centres
- Stainless steel is preferred where stylish looks and enduring quality of finish are a requisite
- Automatic hand dryers use a touchless sensor to activate the device. For most installations this feature is significant benefit, but if installed in a small room this sensor can result in nuisance activation, for example when someone is walking past the unit but not intending to use it. In such situations consideration should be given to the use of a manual hand dryer which is operated by depressing a simple starter button.
- Ultra high speed jet hand dryers use high speed brushless motors that rapidly strip water from wet hands, resulting in very short drying times that are typically measured in seconds rather than tens of seconds.
Hair dryers designed for hotel and similar light commercial applications typically include features such as razor sockets, run-down timers and controllable output temperature.