The needs that Web accessibility aims to address include:
Visual: Visual impairments including blindness, various common types of low vision and poor eyesight, various types of color 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;
Auditory: Deafness or hearing impairments, including individuals who are hard of hearing;
Seizures: Photoepileptic seizures caused by visual strobe or flashing effects.
Cognitive/Intellectual: 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
Individuals living with a disability use assistive technologies such as the following to enable and assist web browsing:
Screen reader software, which can read out, using synthesized 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 computer (used by blind and vision impaired users).
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 Braille keyboard.
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
All about: 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.
On 11 December 2008, the WAI released the WCAG 2.0 as a Recommendation. WCAG 2.0 aims to be up to date and more technology neutral.
Criticism of WAI guidelines
For a general criticism of the W3C process, read Putting the user at the heart of the W3C process. There was a formal objection to WCAG's original claim that WCAG 2.0 will address requirements for people with learning disabilities and cognitive limitations headed by Lisa Seeman and signed by 40 organisations and people. In articles such as WCAG 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.
Other guidelines
Canada
Canada has the Common Look and Feel Standards requiring federal government internet websites to meet Web Content Accessibility Guidelines (WCAG) 1.0 Checkpoints Priorities 1 and 2 (Double A conformance level). The standards have existed since 2000 and were updated in 2007.
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.
Spain
In Spain, UNE 139803 is the norm entrusted to regulate web accessibility. This standard is based on Web Content Accessibility Guidelines 1.0.
Sweden
In Sweden, Verva, the Swedish Administrative Development Agency is responsible for a set of guidelines for Swedish public sector web sites. Through the guidelines, Web accessibility is presented as an integral part of the overall development process and not as a separate issue.
The Swedish guidelines contain criteria which cover the entire lifecycle of a website; from its conception to the publication of live web content. These criteria address several areas which should be considered, including:
accessibility
usability
web standards
privacy issues
information architecture
developing content for the web
Content Management Systems (CMS) / authoring tools selection.
development of web content for mobile devices.
An English translation was released in April 2008: Swedish National Guidelines for Public Sector Websites
The translation is based on the latest version of Guidelines which was released in 2006.
United Kingdom
In December 2010, the BSI (British Standards Institute) released the standard BS 8878:2010 Web accessibility. Code of practice. This standard effectively supersedes PAS 78 (pub. 2006). PAS 78, produced by the The Disability Rights Commission and British Standards Institution, provided guidance to organisations in how to go about commissioning an accessible website from a design agency. It describes what is expected from websites to comply with the UK Disability Discrimination Act 1995 (DDA), making websites accessible to and usable by disabled people.
BS 8878:2010 Web accessibility - Code of Practice. The standard has been designed to introduce non-technical professionals to improved accessibility, usability and user experience for disabled and older people. It will be especially beneficial to anyone new to this subject as it gives guidance on process, rather than on technical and design issues. BS 8878 is consistent with the Equality Act 2010 and is referenced in the UK government’s e-Accessibility Action Plan as the basis of updated advice on developing accessible online services. It includes recommendations for:
Involving disabled people in the development process and using automated tools to assist with accessibility testing
The management of the guidance and process for upholding existing accessibility guidelines and specifications.
BS 8878 is intended for anyone responsible for the policies covering web product creation within their organization, and governance against those policies (e.g. Chief Executive Officers, Managing Directors, Headteachers, ICT managers). It would also assist:
People responsible for promoting and supporting equality and inclusion initiatives within an organization (e.g. Human Resource (HR) managers or those responsible for Corporate Social Responsibility - CSR).
Procurement managers (e.g. those responsible for procuring web products or the tools to create them such as content production systems or virtual learning environments).
Web production teams (e.g. product owners, project managers, technical architects and web developers, designers, usability and accessibility engineers, test engineers).
People with responsibility for creating or shaping online content (e.g. website editors, marketing managers, web content authors).
People who create web production, testing or validation tools.
People who write and deliver training courses in web production, design or coding.
Other audiences that might also be interested in this British Standard include:
Assistive technology creators, vendors and trainers who need insights into how their technologies impact on the production of accessible web products.
Those disabled and older people whose web accessibility needs the Standard aims to support and present.
Japan
Web Content Accessibility Guidelines in Japan was established in 2004 as JIS (Japanese Industrial Standards) X 8341-3. JIS X 8341-3 will be revised within 2009 by adopting WCAG 2.0. New version will have the same 4 principles, 12 guidelines, and 61 success criteria as WCAG 2.0 has.
Essential Components of Web Accessibility
In order for the web to be accessible, 7 components must be included:
the content on Web pages must be natural information (text, images, and sound),
Web browsers and media players,
assistive technologies,
users' knowledge and experience using the Web,
developers,
authoring tools
evaluation tools
These components interact with each other to create an environment that is accessible to people with disabilities.
Web developers usually use authoring tools and evaluation tools to create Web content.
People ("users") use Web browsers, media players, assistive technologies or other "user agents" to get and interact with the content."
Guidelines for Different Components
Authoring Tool Accessibility Guidelines (ATAG)
ATAG contains 28 checkpoints that provide guidance on:
producing accessible output that meets standards and guidelines
promoting the content author for accessibility-related information
providing ways of checking and correcting inaccessible content
integrating accessibility in the overall look and feel
making the authoring tool itself accessible to people with disabilities
Web Content Accessibility Guidelines (WCAG)
All about: Web Content Accessibility Guidelines
WCAG 1.0: 14 guidelines that are general principles of accessible design
WCAG 2.0: 12 principal guidelines
User Agent Accessibility Guidelines (UAAG)
UAAG contains a comprehensive set of checkpoints that cover:
access to all content
user control over how content is rendered
user control over the user interface
standard programming interfaces
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.
Australia
In 2000, an Australian blind man won a court case against the Sydney Organizing 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.
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.
United Kingdom
In the UK, the Equality Act 2010 does not refer explicitly to website accessibility, but makes it illegal to discriminate against people with disabilities. The Act applies to anyone providing a service; public, private and voluntary sectors. The Code of Practice: Rights of Access - Goods, Facilities, Services and Premises document[8] published by the government's Equality and Human 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.
Website accessibility audits
A growing number of organizations, 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.
Accessible Web applications and WAI-ARIA
For a Web page to be accessible all important semantics about the page's functionality must be available so that assistive technology can understand and process the content and adapt it for the user. However as content becomes more and more complex, the standard HTML tags and attributes become inadequate in providing semantic reliably. Modern Web applications often apply scripts to elements to control their functionality and to enable them to act as a control or other dynamic component. These custom components or widgets do not provide a way to convey semantic information to the user agent. WAI-ARIA (Accessible Rich Internet Applications) is a specification published by the World Wide Web Consortium that specifies how to increase the accessibility of dynamic content and user interface components developed with Ajax, HTML, JavaScript and related technologies. ARIA enables accessibility by enabling the author to provide all the semantics to fully describe its supported behaviour. It also allows each element can expose its current states and properties and its relationships between other elements. Accessibility problems with the focus and tab index are also corrected.
All about: Ajax (programming), ARPANET, Austpac, Berners-Lee, Bulletin board system, CYCLADES, Data communication, DCN, Digital divide, Dot-com bubble, E-mail, FidoNet, History of the Internet, History of the World Wide Web, Internet, Internet2, IBM Systems Network Architecture, Internet access worldwide, ICANN, Internet Assigned Numbers Authority, Internet capitalization conventions, Internet Engineering Task Force, Internet governance, InterNIC, Internet Protocol Suite, IPSANET, Len Kleinrock, Leonard Kleinrock, Mobile Web, National Physical Laboratory UK, NSFNet, Packet switching, Packet-switched network, PARC Universal Packet, RAND, Search engine (computing), Simple Mail Transfer Protocol, Sociology of the Internet, Telenet, Tymnet, Usenet, UUCP, Web standards, World Wide Web, X.25, Xerox Network Systems
No comments:
Post a Comment