Several advances in dryer technology address these issues while still maintaining high effectiveness of hand drying and low drying times of 12 seconds or less. These include:

• Digital motor windup and wind down control. New motors employ digital speed regulators that are part of the motor controller package. These have with integral capabilities to correct windup and wind-down performance, which allows precise speed regulation and relatively rapid acceleration while producing minimal acoustic noise.

• Helmholtz technology. Some appliances and building MEP equipment today employ Helmholtz resonators or oscillators to eliminate undesirable high-frequency or low-frequency noise. These noise-cancelling designs typically work by adding a resonant chamber to an exhaust port or other area with moving air or vapor, and the chamber is designed to produce a sound wave that is reflected back to the air stream, canceling the noise. The basic physics are similar to blowing air into an empty bottle to create the cancellation wave.

• Motor tonalities. Research on motors and engines has resulted in a variety of ways to simply engineer the components and enclosure to create more pleasing tonalities and sound quality. These techniques have been applied to automobile and appliance design for decades.

New motor designs include such features as digital motor windup and wind down control to improve precision and acceleration, as well as engineered motor tonalities and Helmholtz resonators or oscillators, which eliminate undesirable high-frequency or low-frequency noise by means of producing noise-cancelling sound waves. Image courtesy of Dyson Inc.

With advances like these, the architect can pay more attention to the sound produced by noisemaking appliances inside the restroom. The result is not only better acoustics but also a valuable way to contribute to user-friendliness and therefore better hygiene and user affinity.

Sustainability and the Environment

There are other potential environmental considerations for designers of restrooms. A few are relatively new and bear consideration.

Health Product Declarations (HPDs)

The use of environmental product declarations (EPDs) has led to wider and more effective adoption of life-cycle assessments (LCAs) as well as more definitive calculations of recycled materials and embodied energy from extraction, manufacturing and transport. This innovation has also led to the creation of an industry group and a method for disclosure of product ingredients and chemical composition. These are called health product declarations or HPDs, and an HPD Open Standard was promulgated in 2012 to accommodate “differences in the ability and readiness of manufacturers to disclose highly variable contents in many diverse products,” according to HPD Collaborative, an industry group that published the standard.¹¹

A number of restroom product manufacturers have completed EPDs and HPDs, and make them available to project teams to ease comparisons about product environmental impacts and formulations. Presented according to accepted protocols and standards, the declarations are now used among manufacturers, end-users, specifiers and suppliers as a basis for project development and for documentation as required by product certifiers and building standards organizations.

The trend is toward “full disclosure” of product formulations and impacts, which has a number of benefits for restroom design. First, products comprising materials and components from multiple sources can provide a full accounting of their supply chain. Second, any chemicals or materials deemed unsuitable for the restroom end-use may be quickly identified. Third, any requests for information (RFIs) on product contents or impact can be sent and answered in a “common format,” says HPD Collaborative.

HPDs provide for an inventory of product contents, and an assessment of those contents against authoritative Hazard Lists, which detail for example toxic agents and known carcinogens, among other dangerous substances. The HPD formats also detail what types of product testing has been undertaken, and what levels and types of compliance the products have achieved. Of note for restroom design, the building operations phase is included in the declarations. EPDs include energy required for operations, for example, and HPDs cover materials required for installation, maintenance, cleaning and operations.

Source Reduction

This raises another important aspect of restroom life-cycle or ROI calculations. The requirements for an energy-consuming device in the operations phase, for example, may vastly exceed it embodied energy from manufacturing and transport. Similarly, the savings from an automatic foam soap dispenser over 10 years may be vastly exceed the initial expense to cover its embodied energy and installation.

The same is true of reduced paper use, which has been the subject of many authoritative studies on the choice between hand-drying methods and appliances.

Paper towels also cause maintenance challenges, ranging from blockages that clog wastewater systems to overflowing trash receptacles. Also there is the need to refill empty towel dispensers, which requires labor hours as well as leaves some portion of paper availability unfulfilled, limiting end-user access and reducing user-friendliness. Yet even more important are the hygiene and image issues relating to paper refuse in the restroom.

Disposing of paper towels, sanitation costs, and transport costs to carry paper towels to the landfill are the primary environmental issues associated with this hand-drying method. As in Clarke's analysis, the college or school district with 4,000 students paying about $0.01 per paper towel would pay $20,000 per year for the paper only. The cost of carting and disposal depends on several variables, but is not included in this figure. For this reason alone, a number of architects and sustainability consultants have been discussing the use of both electric and paper drying or a switch to electric for that 90 percent of nonresidential facilities without them.

One of the bottom-line measures to encourage the use of one method or another is carbon footprint, and the comparison between paper and electric drying methods can show a reduction in total carbon emissions. To demonstrate proof of a product's associated carbon output, there are certifications available, such as the Carbon Trust's carbon reduction labeling program. These certification labels communicate carbon footprint measurement, certification and reduction for specific products and services. There are two “Carbon Footprint” labeling types: Reducing CO₂, which shows that the manufacturer has measured and had certified the carbon footprint of its products and services and, if applicable, the maker's commitment to reducing it. The CO₂ Measured label communicates your achievements in accurately measuring carbon footprint and disclosing the results, according to Carbon Trust.

The use of such labeling is one of a long list of techniques that architects may consider for addressing the myriad issues surrounding commercial restroom design. With the ADA, sustainability issues, ergonomics and comfort in mind, the design team will benefits from a number of potential resources to address complex needs. The development of innovative products—such as high-speed unheated electric hand dryers, including air-knife technology and combined water faucets and electric dryers—is just one of the emerging breed of products and systems to help address the challenges.

 

ENDNOTES
1	http://smallbusiness.chron.com/osha-laws-restrooms-workplace-1332.html
2	http://www.cintas.com/FacilityServices/Press-Releases/Independent-Study-Dirty-Restrooms-Lead-To-Lost-Business.aspx
3	http://www.cdc.gov/healthywater/hygiene/hand/handwashing-corporate.html
4	http://www.cdc.gov/healthywater/hygiene/hand/handwashing-corporate.html
5	http://www.dailymail.co.uk/health/article-2335811/Ditch-hand-dryer-Paper-towels-MORE-hygienic-remove-germs.html
6	http://www.ajicjournal.org/article/S0196-6553%2807%2900595-0/fulltext (“The effectiveness of hand hygiene procedures in reducing the risks of infections in home and community settings...”)
7	http://www.ncbi.nlm.nih.gov/pubmed/17425239
8	http://continuingeducation.construction.com/crs.php?L=31&C=967
9	www.academia.edu/1238491/Sanitary_Ambiance_the_noise_effects_of_high_speed_hand_dryers
10	“Guidelines for Community Noise,” WHO, Geneva 1999
11	http://www.hpdcollaborative.org/use-the-hpd.html

 

Dyson is about developing new technology and making things work better. Environmentally responsible engineering is efficient engineering. Doing more with less. Creating machines that consume less energy and are made of fewer raw materials, but are better performing. Dyson’s function-led approach to design supports this aim. airblade.dyson.com