Web accessibility

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Web accessibility refers to the practice of making Web pages accessible to people using a wide range of user agent software and devices, not just standard Web browsers. This is especially important for people with disabilities such as visual impairment. In order to access the Web, some users require special software or devices in addition to a standard web browser, or specially designed web browsers. Design for accessibility is a sub-category of good design for usability.

The needs that Web accessibility aims to address include:

Contents

[edit] Benefits of Web accessibility

Designing websites with accessibility in mind can often enhance usability for all users. Good design can also deliver easier access for automated software programs that read website content, such as search engines.

One important aspect of accessibility is to let people access content in their preferred way. This can also benefit all users not just those with disabilities: for example, some users may wish to adjust text sizes because they are using a very small display on a mobile phone, or may need to use keystrokes to control their computer because they do not have a mouse or prefer not to use one. Search engines generally cannot make much use of graphics.

Different sites will require different degrees of concern for accessibility. For example,

  • a site providing information specific to Attention-Deficit/Hyperactivity Disorder (ADHD) needs to be easily accessible by people with ADHD
  • a government site of general interest or a resource directory for people in crisis would need to take into account as many disabilities as possible in order to be available to all citizens.

Many people with partial visual impairments or dyslexia will want to change the colours of text or the background to make it easier to read. Users with dyslexia or ADHD will want to stop moving images on the screen because they are easily distracted. People with ADHD may also be confused or distracted by link-rich sites because they can have difficulty when presented with so many options.

For example, hyperlinks that can only be followed by clicking on them with a mouse are impossible to use for those who can only use a keyboard or screen reader to interact with their computer. Information provided only in audio format cannot be accessed by people who are deaf, and if provided only in graphic format information is invisible to people who are blind.

Designing sites in accordance with Web accessibility principles is necessary to enable access for all users.

A set of guidelines [1] and two accessible[2] web portals designed for people developing reading skills are peepo.com [3] — try typing a letter with your keyboard for more — and peepo.co.uk [4] with enhanced graphics, unique style controls and improved interactivity (requires SVG supported browser).

[edit] Technology

[edit] User agent devices

Most people access the Web using a Web browser on a computer. Other ways of accessing the Web include a Personal Digital Assistant (PDA) or a mobile phone. Search engines accessing Web content via a web spider are also common.

A wide range of techniques and technologies are available to facilitate Web access for people with disabilities, or for users in general. These can be divided into two (non-exclusive) classes: enabling technologies, which circumvent a major disability such as blindness; and assistive technologies for lesser impairments.

Enabling technologies include:

  • speech or voice browsers to read textual content aloud.
  • speech-recognition software that can accept spoken commands to the computer, or turn dictation into grammatically correct text.
  • The Braille terminal, 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 a Braille keyboard (either a conventional "QWERTY" type or one designed for the Braille system).

[edit] Assistive technologies

Main article: Assistive technology

In addition to dedicated Web content user agents, a wide range of assistive technologies is available to help people with computer accessibility. These technologies can greatly assist access to Web content for people with disabilities. Examples include:

  • Speech recognition software, which can be useful for those who have difficulty using a mouse or a keyboard.
  • Screen magnification software, which enlarges what is displayed on the computer monitor, making it easier to read for vision impaired users.
  • Keyboard overlays which can make typing easier and more accurate for those who have motor control difficulties.
  • 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 users).
  • Translation software to allow reading of websites in foreign languages especially for those who had been diagnosed to have a learning disability.

[edit] Machine-translation technology

Software which can automatically translate content from one natural language to another is called machine-translation software. This is exemplified by Alta Vista's Babel Fish, a Web site which can translate blocks of text or other Web pages back and forth between English and major European languages. These translations are generally imperfect. Commercial software packages which do a better job can be bought and installed locally on the user's personal computer.

However, in order for these technologies to be fully effective when users are browsing the Web, it is essential that websites are designed to be accessible. The quest for universal Web accessibility is an ongoing attempt to develop Web content so that it is accessible via all user-agent devices for all people.

[edit] The Web Accessibility Initiative (WAI)

Main article: Web Accessibility Initiative

The World Wide Web Consortium (W3C) introduced Web Accessibility Initiative (WAI) to develop Web accessibility guidelines and resources. It seek to provide support materials to help understand and implement Web accessibility.

[edit] Guidelines on accessible web design

[edit] Web Content Accessibility Guidelines

Main article: Web Content Accessibility Guidelines

In 1999 the WAI published the Web Content Accessibility Guidelines WCAG 1.0. These are generally accepted as the definitive guidelines on how to create accessible websites.

Since 2003, the WAI has been working on the second edition of these guidelines, the WCAG 2.0. This is currently at the Working Draft stage.

[edit] Other guidelines

[edit] Philippines

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.

[edit] United Kingdom

In the UK, the Disability Rights Commission (DRC) in collaboration with BSI have published Pas 78 which outlines good practice in commissioning accessible websites.

[edit] 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 discriminated against.

[edit] U.S.

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.

[edit] Australia

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.

[edit] Ireland

In Ireland, the Disability Act 2005 was supplemented with the National Disability Authority's 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.

[edit] United Kingdom

In the UK, the Disability Discrimination Act 1995 (DDA) does not refer explicitly to website accessibility, but makes it illegal to discrimate 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.

[edit] 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 these problems.

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.

[edit] See also

[edit] References

  • Thatcher, Jim, Cynthia Waddell, Shawn Henry, Sarah Swierenga, Mark Urban, Michael Burks, Paul Bohman (2003). Constructing Accessible Web Sites, Reprint, Apress (Previously by Glasshaus). ISBN 1-59059-148-8.
  • Slatin, John, Sharron Rush (2002). Maximum Accessibility: Making Your Web Site More Usable for Everyone. Addison-Wesley Professional. ISBN 0-201-77422-4.

[edit] External links

[edit] Standards and guidelines

[edit] Government regulations

[edit] Resources for users

[edit] Resources for designers

[edit] Web accessibility checkers

[edit] Disability/Impairment Simulators and Other Tools

[edit] Web browser accessibility features

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