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In order to design and create accessible Web sites
it would be useful to define exactly what an accessible Web site actually is.
This will
provide Web developers with a number of useful design guidelines and constraints.
Most countries cite ‘WCAG AA’ as the legal benchmark
in their definition of Web accessibility, the one main exception being the
United States which has provided its’ own guidelines, namely Section
508 of the Rehabilitation Act of 1973. For example, the European Union (EU)
recently passed EU
Law Parliament Resolution (2002)0325 regarding the Accessibility of Public
Web Sites. This was adopted on 13th June 2002.
In note 31 of the resolution the EU has stressed that, for Web sites to be
accessible, it is essential that they are ‘WCAG AA’ compliant.
In other words Priority 2 of the Web Content
Accessibility Guidelines (WCAG) guidelines must be fully implemented. EU legislation
is legally binding on UK courts and therefore should be taken as the legal
definition of Web Accessibility in the UK. Please seek professional legal advice
if you require clarification of the legal situation, both in the UK and elsewhere.
What does 'WCAG AA' or 'Section 508'
actually mean? There are numerous working definitions of Web accessibility
which attempt to
shed some
light
on the subject.
The Open
Training and Education Network,
the largest provider of distance education and training in Australia,
defines an accessible Web site as one in which
‘all users can easily
enter and navigate the site, access all of the information, and use all the
interactive features provided’.
Section
508 of the US Rehabilitation Act 1973 states that a Web site is accessible
when ‘individuals with disabilities can access and use them as effectively
as people who don’t have disabilities’.
The Making Connections
Unit, based in Glasgow Caledonian University in Scotland,
consider four definitions although they actually recommend number 4. An
Accessible
Web site is one that will be: -
- accessible to everyone
- accessible to the intended audience - though perhaps not accessible
to other groups
- accessible to disabled people
- accessible to machines first, and people second.
The definition with perhaps the most authority was written by Chuck
Letourneau,
the man who co-chaired the working group which developed the W3C's Web
Content Accessibility Guideline Recommendation 1.0, the de facto international
standard
for the design of accessible Web sites, and also co-authored the online
training Curriculum for the Web
Content Accessibility Guidelines 1.0.
Letourneau describes Web accessibility thus: - ‘anyone using any
kind of Web browsing technology must be able to visit any site and get a
full and complete
understanding of the information contained there, as well as have the full
and complete ability to interact with the site’.
We will consider a number of key terms derived from Letourneau's definition
of Web accessibility.
'Anyone’
‘ Anyone’ means every person regardless of their sex,
race, age, nationality or ability - from people having the full range of visual,
aural, physical
and cognitive
skills and abilities to those who are limited in one, or more, of them.
‘Any Web Browsing Technology’
Evolt lists
more than 110 different Web browsers, many with numerous
versions.
This
figure includes text-only browsers such as Lynx, speech browsers such
as the IBM Homepage Reader and the Cast E-Reader, as well as
the more popular browsers such as Internet Explorer, Netscape and
Opera.
Web pages can also be viewed by various other devices including screen readers
such as Dolphin Supernova, Personal Digital Assistants (PDA’s), Java
and WAP (Wireless Application Protocol) phones, Web and interactive TV, and
there is even an Internet
fridge.
To comply with Letourneau's accessible Web site definition, pages should be
viewable on all of these devices.
‘Any Site’
‘Any site’ means literally any and all sites.
Some Web developers argue that their site has been created for a specific
group of people and therefore it is not necessary for it to be
accessible . This argument fails on three counts, not counting any
legal ramifications.
- any member of the intended
audience may become disabled at a future time
- disabled users
wishing to join
this selected group are prevented from doing so
- disabled users
who may be interested in the subject matter are prevented from accessing
the
information.
‘Full and Complete Understanding’
There are approximately 6,800 spoken languages with a further 41,000
distinct dialects. The content of the vast majority of Web sites
is written in just one language - English.
For many English is not their first language yet, to comply
with Letourneau's definition of Web accessibility, all Web pages must be fully
and completely understandable to them.
Some sites now use automatic language translation programs. For example,
Google now offer
their search engine Web site in 53 languages and users can set their
user interface preference in one of 88 different languages. Google
also offer a Web page translation service in 12 languages. Unfortunately
the resulting
translations are not always totally accurate and can be confusing.
Even
assuming a visitor is viewing a page written in their native language
there is no guarantee that full understanding will follow. For example, many
academics tend to write using lots of jargon. The words may be English but
the concepts can be
difficult to follow. Web page authors must ensure that their content
is as understandable
as possible.
‘Full and Complete Ability to Interact’
Many Web pages include elements which the user is expected to interact with.
This could include elements such as an online quiz,
an application form or a drag and drop exercise. All users should be able to
fully complete
these activities.
For example, a drag and drop exercise may involve the user dragging various
items from one side of the computer screen and placing them in selected locations
in another part of the screen. This assumes that the user can actually see
the screen and can use a mouse. In order to comply with disability legislation
the exercise must be created so that a visually or physically disabled user
can complete it using alternative methods.
Is it possible to comply with Letourneau's
definition?
Is it really possible to create a site that anyone can use using any kind
of Web browsing technology and get a full and complete understanding of the
site?
In my opinion, the answer is no. There are simply too many variables.
For example,
there are 41,000 different languages and more than 110 different
Internet browsers. Are we seriously expecting Web developers
to create 41,000 different versions of every page and to then test those
pages in every conceivable browser at every conceivable screen resolution?
If we
add another variable, the numbers lose meaning. For example, it is impossible
to estimate the number of different disabilities that people may have and
some people suffer from multiple disabilities.
The implications are that any one individual could sue an organisation
because they could not access a particular Web site despite the best efforts
of the Web developer.
In my opinion, the Web developer has a better chance of complying with disability
legislation if they take a different approach to the problem. The clue to the
solution lies in the fourth definition of Web accessibility put forward by
the Making
Connections Unit, namely, that
an accessible Web site is one which is ‘accessible to machines first,
and people second’.
The one thing that all Internet users have in common is that they must use
some form of Web browser, whether that be an old version of Netscape,
a PDA, or the latest Java enabled telephone. If Web pages could be constructed
in such a way that they would work on all browsers, the Web developer can reduce
the variables considerably.
The answer lies in coding pages in XHTML using
a strict DTD. Strict XHTML is intended to work on all browsers and is fully
backwards, and forwards, compatible.
Strict XHTML does not allow deprecated tags or elements. Pages must be marked-up
correctly resulting in ‘well formed’ documents. The latest
Web browsing technologies require documents to be well formed because they
cannot
interpret badly marked-up documents - they don't have the processing power.
XHTML forces you to code "well-formed" documents
which work in all browsers and are backwards compatible.
Summary
Almost by definition a Web page which is validated to XHTML 1.0 Strict will
display correctly on any and all Web browsers. If Web pages are coded using
XHTML, in conjunction with CSS, the user can format the Web pages to suit
their own preferences. The Web developer therefore need only worry about the
actual
page content.
This approach must give the Web developer a fighting chance in their quest
to create accessible Web pages. |
