This document makes extensive use of the words and concept "universal design." Since the term has been defined and redefined in different ways, we will define the term here in the context in which it will be used within this docum ent. To differentiate it, we will refer to this definition of "universal design" as "UD.tc96" (Universal Design, Trace Center 1996).
This definition is a composite of many people's ideas, and is our best attempt at cap turing the essence, flexibility, and applicability of universal design.
Universal design is the process of creating products (devices, environments, systems, and processes) which are usable by people with the widest possible range of abilities, opera ting within the widest possible range of situations (environments, conditions, and circumstances).
Universal design has two major components:
Universal design is a process which yields products (devices, environments, systems, and processes) which are usable by and useful to the widest possi ble range of people. It is not possible, however, to create a product which is usable by everyone or under all circumsta nces. There are, for instance, people who simultaneously are deaf-blind, have cerebral palsy, and have severe cognitive impairments. We do not currently know how we would design a personal transportation system which could be independently used by an individual with such a combination of impairments. This is rather an extreme case, but it goes to make the point.
An equally important point, however, is the use of the word "currently" in the sentence above. Not long ago, it was not cle ar how we would create public computer-based information displays that were accessible to individuals who were deaf-blind. :Today, we do (as noted later), and it can be done in a way that does not add to the cost of manufacturing the system. In fact, base d on developments within just the last couple of years, it is possible to make products very widely usable and accessible that would not have been possible even a short time ago.
It is important to note that universal design practices are in fact universal. Almost without exception, features or flexibility added to a product to accommodate individuals with termporarily or permanently reduced abilities in some area have proven to be beneficial to users in gen eral. In many cases, more people without a disability will find features useful than the number of people in the original target audience. In fact, universal design cannot be practiced well unless the needs and abilities of everyone (including those with exception abilities on both ends of the spectrum) are taken into account.
Curbcuts are a good example of all of these points. First, they were instigated for people in wheelchairs. However, they are used much more often by people with bicycles, baby carriages, grocery carts, wheeled luggage, or delivery carts than by people in wheelchairs. Early curbcuts, however, were designed with only wheelchair users in mind, and had to be redesigned later to accommodate the needs of individuals who were blind, a nd to ensure that they were safe in cold and icy environments, environments with heavy rainfall, etc. Thus, good universal design benefits everyone, but to do this, it needs to take the needs of everyone into account.
A second example of universal design is the building of closed-caption decoders into television sets. This was done for people who are hard of hearing or deaf, but their use of the decoders has been dwarfed by the use of the feature by people for whom English is a second language, by children learning to read, and by adults using it as a highly motivational and easy mechanism to develop their literacy skills. It is also used by couples to keep peace in the bedroom (when one wants to roll over to sleep and the other wants to continue w atching a program), and by people who want to continue watching the television program while they answer the phone (many TVs actually turn the captions on automatically when the volume is muted).
It is also impor tant to note that the universal design principles not only allow individuals with disabilities to operate products, but also allow individuals who are temporarily function with reduced abilities for other reasons to operate the product. For example, prin ciples which allow an individual who is hard of hearing or deaf to operate a kiosk would also allow everyone else to use the kiosk in the shopping mall at Christmas time, where there is too much noise for the kiosk to be heard. A system which provided an alternative to speech control for those who cannot speak clearly would also be usable by everyone in a library, where speech is not allowed. Interfaces which are usable by individuals without fine pointing control would also be usable by individuals weari ng heavy winter gloves (or a space suit). Systems operable by little people can also be operated by children. Portable communication or information systems that can be operated by people who are blind can also be operated by people driving a car. (Try pi cking a seat on an airplane while driving a car, when the only way that available seats are shown as a picture of the airplane with pink seats for open seats and black seats for seats that are taken.)
Gregg C. Vanderheiden
Trace R&D Center
University of Wisconsin-Madison
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