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Ideas for functional and tech. requirement document.

From: Alan Cantor <acantor@oise.utoronto.ca>
Date: Fri, 9 Apr 1999 10:03:09 -0400 (EDT)
To: WAI Education & Outreach Working Group <w3c-wai-eo@w3.org>
Message-ID: <Pine.SOL.3.91.990409100155.19228B-100000@tortoise>
This is an excerpt from a chapter I wrote on accommodating people with 
disabilities in web-based training programs, to be published later this 
year. I present it to stimulate discussion on how we might organize the 
"Functional and Technical Requirements" document.

Alan

----

A primer on disability

What is disability?

People are not "disabled." A disability is a consequence of design flaws 
in the environment. Some individuals, due to accident, illness, or 
heredity, have difficulties performing -- or cannot perform -- certain 
tasks, such as moving their legs, seeing, hearing, talking, grasping or 
lifting. When these functional limitations are severe enough to adversely 
affect a person's performance, and the natural and human environments 
fail to accommodate their functional limitations, the individual is said 
to have a disability.

Barriers

People with disabilities face barriers that prevent them from realizing 
their full potential. Barriers may be physical, architectural, cultural, 
political, informational, or attitudinal. 

For people with disabilities in computer-based training programs, 
barriers frequently are due to poor planning or design. For example:

1. Most operating systems and software applications include 
poorly-designed features that compromise usability for people with 
certain disabilities.

2. Cyberspace is increasingly multi-media. This characteristic works to 
the advantage of people with disabilities who might not otherwise be able 
to perceive everything on a site. However, if web designers provide 
information in only one format (e.g., images without accompanying text), 
or optimize a site for one particular browser, some people may be unable 
to access all important information.

3. Access barriers result when web-designers do not consider all intended 
users. Making an accessible site is a matter of adhering to simple design 
principles.

Functional limitations

In addition to the barriers posed by poor design and planning, a person's 
functional limitations may make it physically hard to operate a keyboard 
or mouse, read a monitor or printout, or use other peripheral devices. 
Consider the functional limitations associated with seven different kinds 
of disability, and the effects of these limitations on an individual's 
ability to operate a computer:

Visual impairments

Visual impairments range from slightly reduced visual acuity to total 
blindness. A person with reduced visual acuity may have trouble reading 
the screen or distinguishing foreground text from background pattern on a 
web-page. People with more severe impairments rely on technologies that 
translate displayed text into synthesized speech, audible cues, or Braille.

Hearing impairments

Hearing impairments include problems distinguishing certain frequencies, 
sounds or words, ringing in the ears, and total deafness. A computer user 
who is hard of hearing or deaf may miss audible prompts, or not hear 
music and speech that are conveyed through the PC loudspeakers.

Mobility impairments

Mobility impairments include minor difficulties moving or coordinating a 
part of the body, muscle weakness, tremors, and in extreme cases, 
paralysis in one or more parts of the body. Mobility impairments can be 
congenital, such as Muscular Dystrophy; or acquired, such as tendinitis. 
Computer users who have upper-body mobility impairments may be unable to 
manipulate a mouse, press two keys on the keyboard simultaneously, or 
reach certain areas of a keyboard. Others may tend to hit several keys at 
once, or press keys inadvertently.

Cognitive impairments

Cognitive disabilities affect an individual's ability to think and 
reason. They are caused by genetic factors (e.g., Downs Syndrome), 
exposure to environmental toxins (as in Fetal Alcohol Syndrome), brain 
trauma, and psychiatric conditions. Cognitive impairments include memory 
loss, perceptual difficulties, and inability to concentrate. A person 
whose memory has been adversely affected by, say, a head injury, may be 
unable to recall the function of an icon or the menu on which a 
frequently-used command appears.

Learning disabilities

People with learning disabilities have average or above-average 
intelligence, but the ways they take in information, retain it, and 
express knowledge are affected. Learning disabilities affect reading 
comprehension, spelling, the mechanics of writing, manual dexterity, math 
computation, problem solving, processing speed, and the ability to 
organize space and manage time. Students in web-based training programs 
who have learning disabilities may have trouble reading or understanding 
printed materials, picking out pertinent information on a busy computer 
screen, or using a keyboard or mouse.

Seizure disorders

People with certain kinds of epilepsy may have seizures when exposed to a 
monitor that refreshes or a cursor that flashes at particular 
frequencies, or to sounds that repeat at certain rates.

Speech impairments

Speech difficulties do not usually affect one's ability to use a 
computer. In the future, speech impairments might affect computer use if 
voice input technologies become more usable, or if telephone and PC 
applications become fully integrated.

Accommodations for people with disabilities

Accommodations are bridges for overcoming design flaws in the environment 
and individual functional limitations. Accommodation is the process of 
modifying the environment to meet the needs of individuals who have 
difficulties performing tasks that many (perhaps most) other people can 
do. Accommodation involves removing or minimizing the adverse effects of 
barriers in the natural and human environments. These barriers prevent 
individuals with disabilities from achieving personal, educational, 
vocational and recreational goals. 

There are many ways to accommodate an individual in the home, workplace, 
library or classroom, including low-tech devices, spatial reorganization, 
work station modifications and building modifications (See Cantor 1996, 
1998a). In computer-based training programs, most accommodations are 
likely to be adaptive hardware and software.

Adaptive technologies for computer-based training programs

Thousands of hardware and software products are available that allow 
people to overcome design flaws in the environment and their functional 
limitations. Adaptive technologies fall into two broad categories: input 
devices and techniques, and output hardware and software.

Input devices and techniques

- Modified keyboards. Miniature and enlarged keyboards; on-screen 
keyboards operated by switches, eye blinks, puff-and-sip devices, or a 
mouse; adjustable and split keyboards.

- Mouse alternatives. Touch pads, track balls, and graphic tablets.

- Mouse emulators. Software that modifies the keyboard so that the 
numeric keypad (or other keys) can be used to move and click the mouse.

- Keyboard-only techniques. Methods for operating a PC using keyboard 
shortcuts and equivalents instead of a mouse.

- Speech recognition systems. Software and hardware for entering text or 
issuing commands by voice.

- Keyboard and mouse utilities. Software for adjusting the sensitivity 
and behaviour of the keyboard or mouse.

- Word prediction and word completion software. Keystroke-saving programs 
that generate a list of words (or expressions) in response to typing one 
or more letters. For example, typing "wo" displays a menu that includes 
"word," "word prediction," "work," and "would." The user selects the 
desired item from the menu by pressing a key or clicking the mouse.

- Abbreviation expansion software. Programs that instantly translate 
pre-defined codes into words or expressions. For example, typing "AES" 
yields "Abbreviation Expansion Software."

- Macro software. Programs that record a series of commands or 
keystrokes, and replay them by pressing a key or clicking the mouse.

Output hardware and software

- Display properties utilities. Software that alters the size, colour and 
contrast of information on the screen.

- Text-to-speech systems. Hardware and software that convert information 
displayed on the monitor into synthesized speech.

- Text-to-Braille systems. Hardware and software that convert information 
displayed on the monitor to Braille, either through a special printer or 
a refreshable display.

- Visual warning utilities. Software that converts auditory prompts into 
visual cues.

Each person's accommodation needs are unique, and the variations, even 
among people having similar functional limitations, are great. The most 
reliable way to determine an individual's accommodation needs is to ask. 
Assume that the person with a disability is the expert on his or her 
accommodation requirements.
Received on Friday, 9 April 1999 10:03:11 UTC

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