The most notable improvement over traditional hand dryers is the optimization of air performance, which allows for shorter hand drying times. This is achieved in part by more than doubling the air velocity (speed) even though the quantity of air (CFM) is about half that of a traditional hand dryer. The result is that hands can be dry in as little as ten seconds, or three times faster than traditional hand dryers. That puts them on par with the time it can take to dry hands with paper towels.

Improved energy efficiency is achieved in a number of ways. The shorter dry times mean that the dryer is turned off longer using inherently less energy right off the bat. Improvements in the efficiency and design of the electric motor also contribute significantly to energy savings. Further, some manufacturers are offering these new dryers with three-speed power and sound control settings that can be optimized for energy efficiency and user comfort. The power/sound level can be adjusted at high for high traffic restrooms, at low for quiet and low traffic locations, or medium for those in between. The range of electrical demand can vary then from 400 to 1,250 watts or a dramatic decrease from traditional hand dryers that draw 2,300 watts. The range of sound will also vary between 73 to 85 decibels depending on the control setting. Further, the heating element can specified to be switchable allowing it to be turned on in cold weather locations or off in warm weather locations. As a result, it is now possible to specify an electric high speed hand dryer that uses up to 88 percent less energy than traditional hand dryers.

With the increased efficiency and higher acceptance of high speed dryers, building owners and managers can now realistically eliminate paper towels and save dramatically on operation expenses. Even at the rate of 10 cents per kilowatt-hour the cost of using these high-speed dryers is a whopping 99 percent less than the cost of using paper towels. Of course, by eliminating the paper towels altogether, 100 percent of the cost of the waste is eliminated not just for the facility, but for the environment as well.

The cost per dry is commonly calculated showing high-speed energy-efficient hand-dryers with a 99% or better savings compared to paper towels. Calculations are based in this case on average paper towel cost of $0.0152 for one sheet or 1 foot per dry; average commercial price of $0.10 KWH reported by US Energy Information Administration in 2009. Photo courtesy of World Dryer, Inc.

 

Green Building Contributions of High-Speed Hand Dryers

The green building movement in this country has given rise to quantifiable rating systems that seek to establish specific levels of achievement in the creation and performance of green buildings. The best known of these green building rating systems has been developed by the US Green Building Council and known as the LEED® rating system. This is actually a family of ratings that apply to different building situations (e.g., new or existing buildings, core and shell, interiors) and in some cases building types (schools, healthcare, retail, homes, etc.). All of the LEED rating systems have been subject to ongoing changes and updates since their inception, but the basic categories of defining green buildings have remained the same across the different versions over time. With that in mind, the contributions that high-speed hand dryers can make fall into several green building categories:

• Optimize energy performance: High-speed energy-efficient hand dryers can be specified with internal controls that help optimize energy performance of the units and reduce energy use dramatically.

• Materials and resources: In the operation and maintenance of a building, solid waste planning and management is a prominent focus area. Using high-speed energy-efficient hand dryers eliminates the need to dispose of paper hand towels.

• Indoor environmental quality: High-speed energy-efficient hand dryers are pre-finished and require no additional painting or coating in the field. That means that the use of any VOC containing paints or coatings are eliminated. Further, the elimination of paper waste cuts down on the need and use of cleaning supplies to deal with that waste in restrooms.

• Innovation in design: Because of the replacement of paper towels with air hand dryers, innovative prevention of waste may be able to be shown. Additionally, these long lasting products demonstrate favorable life cycle analysis while their use reduces the transportation and embedded energy used in hand drying. It may also be possible to demonstrate innovation for retrofit applications.

Specifying High-Speed Energy- Efficient Hand Dryers

As noted previously, specifying the appropriate hand drying product means recognizing that one size does not fit all situations. Today's hand-dryers offer many more available options and features than their earlier predecessors. Specific hand-dryer features to consider in order to address client requirements while creating an environmentally responsible restroom include the following:

• Automatic operation versus push button: Manufacturers have responded to consumer preferences not to handle something that others already have by minimizing the need to touch any surface in a public restroom whenever possible. Automatic “touchless” operation is clearly preferred anywhere that sanitation is given a high priority such as restaurants and high traffic area restrooms. Touchless hand dryer models prevent cross-contamination from buttons, knobs and levers, proving to be more sanitary than other hand drying alternatives. As an added measure of sanitary control, some of the newer air dryers feature embedded anti-microbial additives that use disinfectant substances to kill or inhibit the growth of microorganisms such as germs, mold, and bacteria as a way of further improving the hand hygiene process. In fact, studies have shown that antimicrobial technology is 99 percent effective against e-coli and MRSA.

• Drying speed controls: One of the biggest advantages of the newest hand dryers is the opportunity to specify them to be adjustable to suit different restroom settings. If this feature is not needed, then single speed models are still available, but having options to change the air flow and the resulting sound levels from location to location without having to keep track of multiple models of dryers certainly makes maintenance and facility management easier. Faster speeds help to ensure adequate drying that avoids the risk of water- based transfer of contaminants while slower speeds reduce noise levels. Manufacturers have commonly built in control switches under the housing that can be accessed by maintenance staff and adjusted accordingly.

High-speed, efficient hand dryers can be specified with intelligent drying controls to suit their location and save energy. The power/ air flow level can be adjusted at high for high traffic restrooms, at low for quiet and low traffic locations, or medium for those in between. The heating element can be switched on in cold weather locations or off in warm weather locations. Photo courtesy of World Dryer, Inc.