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Web Content Accessibility Guidelines: Understanding WCAG 2.0
Posted September 21, 2015
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What You Need to Know
- Under the World Wide Web Consortium (W3C), the Web Accessibility Initiative (WAI) developed the Web Content Accessibility Guidelines (WCAG) 2.0 to produce standards and guidelines to make the web accessible for people with disabilities.
- WCAG 2.0 focuses on website content and structure.
- As a technical standard, WCAG 2.0 primarily establishes guidelines, mainly used by web content developers and tool developers to make websites accessible for people with disabilities.
The Web Content Accessibility Guidelines are the most current and comprehensive in a series of Web accessibility guidelines published by the World Wide Web Consortium (W3C), the primary international standards organization for the World Wide Web. These guidelines assist developers in making content accessible, not only for individuals with disabilities but for all users.
The goals of WCAG are to:
- Connect the world through common information technology and user experience standards
- Provide best-practices for multiple types of devices and software
- Continually evolve and adapt through frequent review and community support
Getting to Know WCAG 2.0
WCAG 2.0 Hierarchy
- Principles: 4
- Guidelines: 12
- Testable Success Criteria: 61
- Priority Conformance Levels: A (25), AA (13), AAA (23)
- Techniques: 450+ (and growing)
For detailed criteria and a complete accessibility matrix, please visit the links provided in the sources list, below
Principles & Guidelines
- Perceivable: Information and user interface components must be presentable to users in ways they can perceive.
1.1. Provide text alternatives for any non-text content so that it can be changed into other forms people need, such as large print, braille, speech, symbols or simpler language.
1.2. Provide alternatives for time-based media.
1.3. Create content that can be presented in different ways (for example simpler layout) without losing information or structure.
1.4. Make it easier for users to see and hear content including separating foreground from background.
- Operable: User interface components and navigation must be operable.
2.1. Make all functionality available from a keyboard.
2.2. Provide users enough time to read and use the content.
2.3. Do not design content in a way that is known to cause seizures.
2.4. Provide ways to help users navigate, find content, and determine where they are.
- Understandable: Information and the operation of user interface must be understandable.
3.1. Make text content readable and understandable.
3.2. Make Web pages appear and operate in predictable ways.
3.3. Help users avoid and correct mistakes.
- Robust: Content must be robust enough that it can be interpreted reliably by a wide variety of user agents, including assistive technologies.
4.1. Maximize compatibility with current and future user agents, including assistive technologies.
Techniques are technology-specific (General, HTML, CSS, ARIA, etc.)
- Types include
Sufficient – minimum requirements
Advisory – additional improvements
Failure – often encountered mistakes
- Contents include
The Five Conformance Requirements
Number 1: Conformance Levels.
Level A is considered the minimum degree of accessibility and covers basic web accessibility. Level AA is considered the mid-range degree of accessibility and covers the most common barriers people with disabilities encounter on the web. The highest degree is Level AAA and is the uppermost level that can be reached for website accessibility.
The standard conformance degree is Level AA.
If you have conformance at a higher level, you will have conformance at the below levels. For example, if you comply with Level AAA, you also comply with Level AA and A and if you comply with Level AA, you also comply with Level A.
Number 2: Full Pages.
Full pages must conform to the conformance level. Parts of pages must not be excluded to meet conformance.
Number 3: The Complete Process.
If more than one page is part of a process that is needed to complete a product or activity, they must all meet the conformance level to the same degree. The only way that it is accessible, is if the web page meets the same or higher conformance level than the rest.
Number 4 & 5: Usability of Accessibility Supported Technologies
In short, web pages must be accessible to people using assistive technologies and user agents. If technology is used on the web page that is not accessibility supported, it must not block or create barriers for technology that is accessibility supported.
The Department of Justice & WCAG 2.0
The U.S. Department of Justice has reached settlements with places of public accommodation to have their websites use the guidelines set forth in WCAG 2.0 to become compliant with the Americans with Disabilities Act. This can be seen in their settlement agreements with higher and k-12 educational organizations, as well as counties and towns. Consistently, the DOJ has demonstrated that they are enforcing website accessibility and using WCAG 2.0 standards to do so.
An Internationally Accepted Standard
Around the world, other countries are introducing website accessibility laws that reference the use of WCAG 2.0 Standards. WCAG 2.0 has become a global standard for website accessibility.
WCAG is quickly being embraced as the international standard and has been directly referenced or adopted by 14 countries and the European Union. Australia, Canada, France, Germany, Hong Kong, India, Ireland, Japan, Netherlands, New Zealand, Norway, Spain, and the United Kingdom use or base their laws off WCAG 2.0 for website accessibility.
There are countless references on the web, that provide great detail on the many nuances of WCAG. Start with the materials to below, if you are just getting to know the guidelines.
World Wide Web Consortium
Introduction to WCAG
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