Web Design & Development Guide
Web Content Accessibility Guidelines
Web accessibility refers to the practice of making
usable by people of all abilities and
disabilities. When sites are correctly designed, developed and edited,
all users can have equal access to information and functionality. For
example, when a site is coded with semantically meaningful HTML, with
textual equivalents provided for images and with links named
meaningfully, this helps blind users using text-to-speech software
and/or text-to-Braille hardware. When text and images are large and/or
enlargable, it is easier for users with poor sight to read and
understand the content. When links are underlined (or otherwise
differentiated) as well as coloured, this ensures that colour blind
users will be able to notice them. When clickable links and areas are
large, this helps users who cannot control a mouse with precision. When
pages are coded so that users can navigate by means of the keyboard
alone, or a single switch access device alone, this helps users who
cannot use a mouse or even a standard keyboard. When videos are closed
captioned or a sign language version is available, deaf and hard of
hearing users can understand video. When flashing effects are avoided or
made optional, users prone to seizures caused by these effects are not
put at risk. And when content is written in plain language and
illustrated with instructional diagrams and animations, users with
dyslexia and learning difficulties are better able to understand the content.
When sites are correctly built and maintained, all of these users can be
accommodated while not impacting on the usability of the site for
The needs that Web accessibility aims to address include:
Visual impairments including blindness, various common types of low vision
and poor eyesight, various types of colour blindness;
- Motor/Mobility: e.g. difficulty or inability to use the hands,
including tremors, muscle slowness, loss of fine muscle control, etc., due
to conditions such as
Parkinson's Disease, muscular dystrophy, cerebral palsy, stroke;
Deafness or hearing impairments, including individuals who are hard of
- Seizures: Photoepileptic
caused by visual strobe or flashing effects.
Developmental disabilities, learning disabilities (dyslexia, dyscalculia,
etc.), and cognitive disabilities of various origins, affecting memory, attention,
developmental "maturity," problem-solving and logic skills, etc.;
Assistive technologies used for web browsing
Disabled users use
assistive technologies such as the following to enable and assist web
Screen reader software, which can read out, using synthesised speech,
either selected elements of what is being displayed on the monitor (helpful
for users with reading or learning difficulties), or which can read out
everything that is happening on the PC (used by blind and vision impaired
Braille terminals, consisting of a Refreshable Braille display which renders
text as Braille characters (usually by means of raising pegs through holes
in a flat surface) and either a QWERTY or
Screen magnification software, which enlarges what is displayed on the
computer monitor, making it easier to read for vision impaired users.
Speech recognition software that can accept spoken commands to the
computer, or turn dictation into grammatically correct text - useful for
those who have difficulty using a mouse or a keyboard.
- Keyboard overlays which can make typing easier and more accurate for
those who have motor control difficulties.
Guidelines on accessible web design
Web Content Accessibility Guidelines
In 1999 the Web Accessibility Initiative, a project by the
World Wide Web Consortium (W3C), published the
Web Content Accessibility Guidelines
WCAG 1.0. In recent years, these have been widely accepted as the definitive
guidelines on how to create accessible websites.
Since 2003, the WAI has been working on the second edition of these
WCAG 2.0, which aim to be up to date and more technology neutral. This is
currently at the
Working Draft stage.
Criticism of WAI guidelines
In articles such as
WCAC 2.0: The new W3C guidelines evaluated,
To Hell with WCAG 2.0 and
Testability Costs Too Much, the WAI has been criticised for allowing WCAG
1.0 to get increasingly out of step with today's technologies and techniques for
creating and consuming web content, for the slow pace of development of WCAG
2.0, for making the new guidelines difficult to navigate and understand, and
other argued failings. In one attempt to provide guidelines that are designed to
be up to date, easier to understand, and more relevant and practical to typical
web development projects, Joe Clark's
WCAG Samurai project has published an unofficial set of errata to WCAG 1.0.
As part of the
Web Accessibility Initiatives in the Philippines, the government through the
National Council for the Welfare of Disabled Persons (NCWDP) board approved the
recommendation of forming an adhoc or core group of webmasters that will help in
the implementation of the Biwako Millennium Framework set by the UNESCAP.
The Philippines was also the place where the Interregional Seminar and
Regional Demonstration Workshop on Accessible Information and Communications
Technologies (ICT) to Persons with Disabilities was held where eleven countries
from Asia - Pacific were represented. The Manila Accessible Information and
Communications Technologies Design Recommendations was drafted and adopted in 2003.
In the UK, the Disability Rights Commission (DRC) in collaboration with BSI
have published Pas 78 which
outlines good practice in commissioning accessible websites.
Legally required web accessibility
A growing number of countries around the world have introduced legislation
which either directly addresses the need for websites and other forms of
communication to be accessible to people with disabilities, or which addresses
the more general requirement for people with disabilities not to be
In 2000, an
Australian blind man won a court case against the Sydney Organising Committee of
the Olympic Games (SOCOG). This was the first successful case under Disability
Discrimination Act 1992 because SOCOG had failed to make their official website,
Sydney Olympic Games, adequately accessible to blind users. The Human Rights
and Equal Opportunity Commission (HREOC) also published
World Wide Web Access: Disability Discrimination Act Advisory Notes. All
Governments in Australia also have policies and guidelines that require
accessible public websites; Vision Australia maintain a complete list of
Australian web accessibility policies.
Disability Act 2005 was supplemented with the National Disability
Code of Practice on Accessible Public Services in July 2006. It is a
practical guide to help all Government Departments and nearly 500 public bodies
to comply with their obligations under the Disability Act 2005.
In the UK, the Disability Discrimination Act 1995 (DDA) does not refer explicitly to
website accessibility, but makes it illegal to discriminate against people with
disabilities. The DDA applies to anyone providing a service; public, private and
voluntary sectors. The
Code of Practice: Rights of Access - Goods, Facilities, Services and Premises
document published by the government's
Disability Rights Commission to accompany the Act does refer explicitly to
websites as one of the "services to the public" which should be considered
covered by the Act.
In the U.S., the Section 508 of the Rehabilitation Act requires that Federal
agencies and their contractors give disabled employees and members of the public
access to information (including web sites) that is comparable to the access
available to others; the Americans with Disabilities Act of 1990 prohibits
discrimination on the basis of disability; and Section 225 of the
Telecommunications Act of 1996 requires suppliers to make telecommunications
products and services accessible unless not requiring significant difficulty or
expense. It is complicated, and dependent on case law, exactly how the latter
two apply to Web site accessibility.
On September 7, 2006, Judge
Marilyn Hall Patel ruled in National Federation of the Blind v. Target
Corporation that a retailer with a physical storefront may be sued if its
website is inaccessible to the blind. However, Judge Patel did not rule on the
merits of the plaintiff's case, which will be adjudicated at a later
Website accessibility audits
A growing number of organisations, companies and consultants offer website
accessibility audits. These audits, a type of
system testing, identify accessibility problems that exist within a website,
and provide advice and guidance on the steps that need to be taken to correct
A range of methods are used to audit websites for accessibility:
- Automated tools are available which can identify some of the problems
that are present.
- Expert technical reviewers, knowledgeable in web design technologies and
accessibility, can review a representative selection of pages and provide
detailed feedback and advice based on their findings.
- User testing, usually overseen by technical experts, involves setting
tasks for ordinary users to carry out on the website, and reviewing the
problems these users encounter as they try to carry out the tasks.
Each of these methods has its strengths and weaknesses:
- Automated tools can process many pages in a relatively short length of
time, but can only identify some of the accessibility problems that might be
present in the website.
- Technical expert review will identify many of the problems that exist,
but the process is time consuming, and many websites are too large to make
it possible for a person to review every page.
- User testing combines elements of usability and accessibility testing,
and is valuable for identifying problems that might otherwise be overlooked,
but needs to be used knowledgeably to avoid the risk of basing design
decisions on one user's preferences.
Ideally, a combination of methods should be used to assess the accessibility
of a website.
Thatcher, Jim; Cynthia Waddell, Shawn Henry, Sarah Swierenga, Mark Urban,
Michael Burks, Paul Bohman (2003). Constructing Accessible Web Sites,
Reprint, Apress (Previously by Glasshaus).
Slatin, John; Sharron Rush (2002). Maximum Accessibility: Making Your Web
Site More Usable for Everyone. Addison-Wesley Professional.
Standards and guidelines
Resources for users
Resources for designers
Web accessibility checkers
Disability/Impairment Simulators and Other Tools
Web browser accessibility features
Web development software
Web security exploits