How Do Hand Dryers Work?

From restaurants to grocery stores to private residences, air hand dryers have become commonplace technology. Automatic hand dryers offer hand drying with less mess and maintenance—and up to 95% cost savings—when compared to using a paper towel dispenser. With increasingly advanced hand dryer options hitting the market year after year, you may have stopped to wonder how exactly a hand dryer works. Let’s take a look at how a hand dryer does its job for millions of people around the world every day.

At its most basic, the hand dryer is a type of wall fan heater. It heats up air from the surrounding area and blows it back out into the room. The difference between a hand dryer and wall fan heater is that a hand dryer doesn’t get as hot, doesn’t run for hours at a time, doesn’t attempt to heat an entire room, and is specifically made to operate in restrooms, though not every wall fan heater is made to be installed in a bathroom area.

The infrared sensor or push button is what kicks off the entire hand-drying process. Sensors are activated by motion and a push button has to be pressed by the user. Either of these signals the hand dryer to start.

The motor is activated once movement is detected. It first pulls air in through the intake vents that are usually crafted into its sides. These vents allow the air to be carried through filters before getting to the motor. Once the cleaned air passes through the motor, it is forced out as speeds of up to 420 miles per hour. The air passes over heating elements (usually electrically heated pieces of metal) and is funneled into one or two nozzles. Under this nozzle outlet is where you hold your hands for drying purposes.

The universal standard for air dryers is to have vents, a motor, and a nozzle or duct for the outgoing air. Everything else is optional. The hand dryer may not have a heating element to warm the air as it blows, and it may not include the ability to house filters to clean the incoming air. It may or may not have the ability to push the air out at high speeds or include insulation or padding to help reduce noise. Whenever you’re ready to purchase a hand dryer for personal or commercial purposes, be sure it has everything that you’re looking for.

Voltage is a major factor when it comes to choosing a hand dryer. Hand dryers can range in voltages from 100 to 240 volts. You will first need to make sure you know what the voltage is in the building where you will be installing the hand dryer. Then you will need to make sure that the hand dryer that you purchase is compatible with that voltage. For example, if your building has a 120-volt circuit, you need to make sure that you purchase a hand dryer that can handle 120 volts of power.

The quantity of hand dryers you’ll need is also a factor. In busy restrooms, a single hand dryer can lead to long lines and frustrated customers throughout your store. In most commercial spaces, a minimum of two dryers per restroom is recommended.

Installation height can also be an issue. In most restrooms, you’ll want to make sure that at least one of your hand dryers is accessible to someone in a wheelchair and visually impaired people using canes. This will mean installing the hand dryer lower on your wall. If you run an establishment where there are often children present (an indoor playground or an amusement park, for example), you’ll also want to install some or most of your dryers at a lower height, though you’ll still want parents to be able to use the hand dryer. For dryers that blow air down onto hands (“hands under” dryers), you will usually mount them somewhere between 32 and 46 inches above the floor. To make the dryer comfortable for children and people using wheelchairs and canes, mount them lower. The Americans with Disabilities Act (ADA), recommends they be mounted only 27 inches off the floor.

Wall and floor care entails making sure that all the water that is blown off of people’s hands doesn’t pool on your floor or spray all over your painted walls. There are covers for the space under your dryer to help with protecting your wall from water spots and damage. Water on the floor is less of an issue in restrooms that aren’t as busy. But in bustling stores, parks, or offices, this could become a slip or fall hazard.

Now that you know how a hand dryer works and have been introduced to a few things to consider before you buy, take a look at the HomElectrical selection of hand dryers. Give us a call at 1-888-616-3532 and we’ll get you set up for cleaner, more cost-efficient restrooms today!