Accessibility according to Wikipedia describes the degree to which a system is usable by as many people as possible without modification. In particular, it is one of the attributes that should be tested for websites. Being visually-challenged affects more of your audience than you might think. Most know that up to 10% of men and up to 3% of women suffer from various degrees of color-blindness. With aging populations, more and more people have decreasing visual acuity. These factors may affect what part of your website's audience find the website satisfactory. The following post summarizes some of the issues related to Accessibility.
Accessibility now has increasing legal force behind its application. The following is a summary from Wikipedia:
In general, the UK has been a leader in this field. Two Cre8asite threads provided more detail:
In the US, the Section 508 of the Rehabilitation Act requires that federal agencies' web sites be accessible to people with disabilities.
In Australia, the Disability Discrimination Act 1992 was used successfully by a blind man in 2000 since the official website of the Sydney Olympic Games was not adequately accessible to blind users.
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.
UK Accessibility Report by the DRC
Web accessibility required by law in UK
There are teeth in this legislation as may be seen in a recent thread:
Class Action Suit: Blind vs Target, Blind can't "read" Target's site
Making sure that websites are accessible may be costly as shown in another thread: £100,000 to fix inaccessible site. There are some fundamental steps to take as set out in 10 Things you should know about Accessibility. At the same time, there can be other benefits as Andy Hagans suggested in High Accessibility Is Effective Search Engine Optimization.
To be aware of what is currently happening in this area, you may wish to check out the Accessify Forum. It has a specific Forum on Building and Testing. Although this is mostly on physical accessibility issues, it does cover web design as well. Another source is the Web Accessibility Portal. This includes a section on Tools and Software. Another source is the Web Accessibility Tool Consortium (WAT-C). There are also other tools to be found on the Web such as WebXACT. This is a free online service that lets you test single pages of web content for quality, accessibility, and privacy issues.
Accessibility is a very big topic, so some degree of caution is appropriate. That is highlighted in another thread: Why you shouldn't rely on Accessibility Checking Tools.
Given the size of the Accessibility topic, the Cross-Browser Device Accessibility Panel (CDAP) is unlikely to give a complete and thorough accessibility review of any given website. The thoroughness will depend on the time availability and goodwill of those volunteers who can usefully comment. It can be hoped that at least it will flag websites with significant problems. It will also make more people aware that Accessibility is an important issue that should not be neglected.
Edited by bwelford, 06 March 2006 - 08:52 PM.