A good starting point is Aaron Leventhal's article
Software Accessibility - Where Are We Today?.
which discusses the progress that has been made in two decades of work on making computers
accessible. As for why we should make the web accessible, there are several
possible answers:
Scott McNealy, CEO of Sun Microsystems, makes an essentially economic argument:
It doesn't take a visionary to know building accessibility into the desktop is the right thing
to do for your business environment. Making accessibility a reality provides users with disabilities
a higher quality computing experience. It levels the playing field for your most important
commodity - your employees. Since the
Americans with Disabilities Act of 1990 (ADA)
requires workplaces which engage in interstate commerce and have more than 15 employees to
avoid discriminating against disabled employees, better computer accessibility will increase employee
productivity in most contemporary workplaces.
The trend to widespread commercial use of handheld devices to access the
web has created a demand for pages that look good on a small screen. Often
these look good to screenreaders too.
Lorelle VanFossen's
design guidelines for photographers shows the effects of
different screen sizes (including PDAs), fonts, and colors.
Web designers often mistakenly assume that
designing for people with disabilities means giving up multimedia and the "latest" design tools (and fads).
Standards, Laws and Guidelines
The World Wide Web Consortium's
Web Accessibility Initiative has guidelines for
web content authors
and authoring tool developers. W3C is considered
the world's standard setting organization for the web.
The U.S. government's requirement that it's information technology be accessible is known as
Section 508. This refers to a specific section of the
1998 Rehabilitation Act.
Many other countries have similar legisltion.
While the U.S. law does not apply to corporate or individual
webpages, the European Union is moving towards requiring universal web access with it's 2002 resolution.
The United Kingdom's requirement of web accessibility for all webpages stimulated
entrepeneurial web design activitiy.
The U. S. National Instructional
Materials Accessibility Standard (
NIMAS) guides the production and electronic
distribution of digital versions of textbooks and other instructional materials so they can be
more easily converted to accessible formats, including braille and text-to-speech.
Apple was the first company in the industry to support disability access. Their products are described at
http://www.apple.com/accessibility/.
Apple has integrated a
magnifier
and spoken interface in Os X.
Microsoft's site is
http://www.microsoft.com/enable/.
Adobe
provides free accessibility tools for reading .pdf files.
Macromedia flash now allows users of their authoring tools to create
accessibe flash.
Adobe's best practices whitepapers for
pdf
authors make it clear that the toolmakers cannot
create an accessible web without the participation of content producers.
Designing for accessibility takes time, which makes it expensive unless
toolmakers integrate accessibility into the main functions of
their tools instead of making it an option. Until accessible standards become easy to use
and the default option for document authoring tools, much web content will remail inaccessible.
Non-Governmental Organizations
As an example of the many partnerships bewteen technology companies and
advocacy organizations for the disabled, the American Foundation for the Blind has been working with Adobe
to improve
the accessibility of pdf documents. However many creaters of pdfs scan in an image of text
(rather than text itself) which cannot be read with screenreaders. Optical Character Readers can read
pages and images of text allowed, but often cannot handle the crooked and blurred pages that result
from hurried scans of documents into pdf.
Until recently, accessibility in linux involved a great deal of work for users.
A HOWTO was available,
a mailing list and archives were maintained by the BLINUX Project,
and a full-featured (though complicated) text to speech interface was available through the
Emacspeak audio desktop for Linux.
More recently, an accessibility project was supported by Sun for the
Gnome Desktop.
Gnome Desktop development is continuing with the Orca and
LSR projects.
The popular ubuntu linux distribution includes
accessibility features very similar to
those available for Windows and Os X..
Web Browsers
A 2005 list of web browsers and screen readers
designed for persons with disabilities
shows the diversity of clients available for the disabled. The World Wide Web Consortium is
currently working on
Accessibility Guidelines
for the next generation of browsers and readers.
The Mozilla organization has a project to make it's firefox
web browser and other products more accessible, as seen in this
presentation. As cloud computing develops, more accessibility solutions like the University of
Washington's WebAnywhere project are likely to emerge. It offers a free, cross-platform,
and widely available spoken web.
Multimedia Content
Boston's WGBH is considered an outstanding model of accessible web design. It's National Center fpr Accessible Media
offers information about making streaming, animation and intereactive web content accessible.
Technological Innovation for Physical Disability Access
Physically impaired computer users use a variety of hardware interfaces to meet their needs.
Examples are Origin Instruments' headmouse and
single switch input device
Videos of people using single switch controls are distributed via YouTube
by Assistiveware.
Hardware developers
have adapted the computer mouse to control the
hand tremors that affect many people with chronic illnesses or be worn as
headgear.
The trend to widespread commercial use of handheld devices to access the
web has created a demand for pages that look good on a small screen. Often
these look good to screenreaders too.
Lorelle VanFossen's
design guidelines for photographers shows the effects of
different screen sizes (including PDAs), fonts, and colors.
Web designers often mistakenly assume that
designing for people with disabilities means giving up multimedia and the "latest" design tools (and fads).
Multimedia pages can be accessible, as these examples show:
BT.com maintains a page of
Developers Tools to help web designers create images that most "colorblind"
people can distinguish. The 256 color websafe palette is also good
for people using a variety of older monitors.
Visicheck's online simulator lets you see how images will look to color deficient people. Other tools are available at
For
VisiBone's site.
The Ishihara Test for Color Blindness
will let you see if you are one of the 8 % of men or < 1 % of women who are.
Verify Your Page
Writing your web pages to meet universal standards is one of the best ways to ensure accessibility. Pages written to work
with only one browser do not usually work well with screen readers
and other accessible technologies.
IBM's
aDesigner tool lets you see what your web pages will look like under a variety of different
vision conditions including blindness, low vision, and three varieties of color deficiency.
To see if your pages are standard HTML,
you can validate them with the Worldwide Web Consortium's
Tidy tool, which can be downloaded from Sourceforge for most operating systems. The online version of the
Cynthia Says tool can be used to validate a few pages.
the World Wide Web Consortium's
Web Content Accessibility Guidelines 1.0 or the U. S. government's Section 508 compliance.
Use a Text-Only Browser
Text-only browsers such as lynx can be used as a tool to see what someone using a screen reader would hear.
It can be installed on Windows machines, where it runs in a DOS shell, or can be run from unix, linux, or
Mac Os X machines.
From a unix shell at the College of Computer Science type the command
lynx www.ccs.neu.edu/home/perrolle/access/webdesign.html
to look at this page. Or you can use DJ Deloria's lynx viewer.
He also offers an online tool to test what your page would look like in
older browsers.
