[DRAFT] How to Transition Your Web Site from WCAG 1.0 to WCAG 2.0
Note: This old draft has been superseded. A more
recent draft is available, and the final version will be available from
the WCAG Overview.
Note: This document is a draft in development,
and should not be referenced or quoted under any circumstances.
$Date: 2008/11/21 14:02:34 $ changelog]
Page Contents
- Introduction
- Step 1. Learn the Basic Differences
- Step 2. Define Your Conformance Parameters
- Step 3. Analyze How the WCAG 2.0 Technical Requirements Apply
- Step 4. Evaluate How Your Site Meets WCAG 2.0
- Step 5. Plan and implement Changes to Your Site
- Step 6. Update any Internal Guidance and monitor updates (find better heading)
[changelog: Review the approach of the document so that the primary focus is Step 3 with the introduction covering 1 and 2]
Introduction
This document provides key steps for designers, developers, and project managers transitioning Web sites from Web Content Accessibility Guidelines (WCAG) 1.0 to WCAG 2.0. [See the Benefits of Transitioning to WCAG 2.0 for...]
The accessibility work that you did for WCAG 1.0 will be useful for meeting WCAG 2.0. In most cases only minimal work will be needed to transition to WCAG 2.0. Sites that meet WCAG 1.0 will already be a long way to fulfilling WCAG 2.0 and should not require significant changes in order to meet to WCAG 2.0.
[changelog: WCAG 2.0 builds on wcag 1.0. WCAG 2.0 is backwards compatible with WCAG 1.0, meaning that it is possible to update your Web site in a way that will meet both.] WCAG 2.0 builds on WCAG 1.0 and is backwards compatible with WCAG 1.0. If your site is required to meet WCAG 1.0, you may choose to update it to meet both WCAG 1.0 and WCAG 2.0.
[changelog: Add an image of a venn diagram to show the overlaps and differences of WCAG 1.0 and 2.0]
[The following steps... @@... links to documents that provide additional guidance for each step.]
[changelog: Review the approach of the document so that the primary focus is Step 3 with the introduction covering 1 and 2]
Step 1. Learn the Basic Differences
Resource: Overview of WCAG 2.0 Documents
Read the Overview of WCAG 2.0 Documents to learn how WCAG 2.0 differs from WCAG 1.0 in approach and terminology, such as "Checkpoints" and "Priority" in WCAG 1.0, versus "Success Criteria" and "Levels" in WCAG 2.0.
Note: What we refer to as "requirements" in this document include the WCAG 1.0 Checkpoints and the WCAG 2.0 Success Criteria.
Step 2. [Decide | Decare | Understand | Know | Re-examine Your Conformance Levels | Define Your Conformance Parameters]
Resource: WCAG 2.0 Conformance
Note: The WCAG 2.0 conformance [model|scheme] is
being significantly revised; it will be available in 2007.
Read WCAG 2.0 Conformance to learn:
- The 3 levels of Success Criteria in the WCAG 2.0 conformance scheme.
- How the technologies that are relied upon and technologies that are used but not relied upon within your site impact conformance.
- How conformance claims can be scoped.
[changelog: Look at the first full sentence and edit it to audience for whom the conformance level is already defined] In order to know which WCAG 2.0 requirements you need to meet, first you need to define your target conformance level.
Your conformance level might be impacted by regulations for your country, region, or type of organization. For example, you may be required to meet Level 1 and Level 2 Success Criteria, called "Double-A (AA)". Legal and Policy Factors in Developing a Web Accessibility Business Case for Your Organization and International Policies Relating to Web Accessibility help determine what requirements apply to your organization.
If your organization already has an accessibility policy that is updated to WCAG 2.0, the conformance level is probably included in it. If you don't have an accessibility policy, [changelog: make stronger you may be interested in] the Developing Organizational Policies on Web Accessibility document. For those who have a policy referencing WCAG 1.0, WAI plans to provide a document in the future with guidance on transitioning Web accessibility policies from WCAG 1.0 to WCAG 2.0.
Step 3. Analyze How the WCAG 2.0 Technical Requirements Apply to Your Site
Resources:
- WCAG 2.0 Quick Reference
- Understanding WCAG 2.0
- Techniques for WCAG 2.0
- Comparison of WCAG 1.0 Checkpoints to WCAG 2.0
Note: While the basic information in these documents is complete, some deatils are changing. Revised documents will be published in 2007.
[changelog: Remove "customize" and use something that highlights that the Quick Ref documents helps you "identify"] You can customize the WCAG 2.0 Quick Reference to list the Success Criteria that applies to your selected conformance level and the technologies that your site uses.
One way to approach analyzing the WCAG 2.0 requirements is to first review the WCAG 2.0 requirements that relate to WCAG 1.0, and then the new WCAG 2.0 requirements. As shown in the Comparison of WCAG 1.0 Checkpoints to WCAG 2.0, there is not a direct one-to-one mapping between WCAG 1.0 Checkpoints and WCAG 2.0 Success Criteria.
3.1. Check WCAG 1.0 Checkpoints that Relate to WCAG 2.0 Success Criteria
[changelog: 3.1 - 3.2: Look at either breaking down the sections to re-worded headings and examples or, headings, sentence explanation and sidebar examples.]
[Key questions to ask your self are: @@]
- Does your site already meet WCAG 2.0 requirements that are
similar to WCAG 1.0 requirements?
Some WCAG 2.0 Success Criteria are similar to WCAG 1.0 Checkpoints; for example, the WCAG 1.0 Checkpoint 1.1 "Provide a text equivalent for every non-text element" is similar to the WCAG 2.0 Success Criteria for Guideline 1.1 "Provide text alternatives for all non-text content". You may already meet the WCAG 2.0 requirements that are similar to WCAG 1.0. [changelog: look at the use of the text equivalents as an example to see if there is another possible alternative]
- [changelog: Simplify the heading along the lines of "Are there
requirements in WCAG 1.0 that your site no longer needs to meet"]
Are there requirements in WCAG 1.0 that your site didn't meet,
that it no longer needs to meet in WCAG 2.0
Some requirements from WCAG 1.0 are now no longer required in WCAG 2.0; for example, WCAG 1.0 Checkpoint 10.5 "Until user agents (including assistive technologies) render adjacent links distinctly, include non-link, printable characters (surrounded by spaces) between adjacent links." Note that most of the requirements from WCAG 1.0 that are no longer required for 2.0 are still beneficial and suggested as "Advisory Techniques".
- Are there requirements in WCAG 1.0 that your site didn't meet,
that it does meet in WCAG 2.0?
Some WCAG 2.0 requirements provide more flexibility and [design freedom] than WCAG 1.0. For example, WCAG 1.0 Checkpoint 7.1 "Until user agents allow users to control flickering, avoid causing the screen to flicker" prohibited many kinds of movement in Web pages. WCAG 2.0 allows more movement within defined parameters, such as in Success Criteria 2.3.1 and 2.3.2. You may be able to meet the more relaxed WCAG 2.0 requirements even though your site did not meet the related WCAG 1.0 requirements.
- Do WCAG 2.0 requirements have more specific Success Criteria
that you need to address?
Some WCAG 2.0 requirements are more specific than the related requirements in 1.0, primarily to make them more testable. For example, WCAG 1.0 Checkpoint 2.2 "Ensure that foreground and background color combinations provide sufficient contrast" is vague, whereas WCAG 2.0 Success Criterion 1.4.1 "Text or diagrams, and their background, have a luminosity contrast ratio of at least 5:1" is very specific. You may need to make revisions to meet more specific WCAG 2.0 Success Criteria.
3.2. Check New WCAG 2.0 Success Criteria
WCAG 2.0 Success Criteria that are not closely related to 1.0 Checkpoints are listed at the bottom of Comparison of WCAG 1.0 Checkpoints to WCAG 2.0. [Key questions to ask are:]
- Which new WCAG 2.0 Success Criteria are already implemented in
your site?
You might already meet new 2.0 requirements. For example, many sites designed for accessibility will already meet Success Criterion 1.3.5 "Information required to understand and operate content does not rely on shape, size, visual location, or orientation of components".
- Which new WCAG 2.0 Success Criteria are not implemented in your
site?
There may be some new WCAG 2.0 requirements that you don't fully meet. For example, there are additional requirements relating to error handling such as Success Criterion 2.5.1 "If an input error is detected, the error is identified and described to the user in text".
Step 4. Evaluate How Your Site Meets WCAG 2.0
[changelog: Consider if any of the information from 4 and 5 is relevant.]
Resources:
- Evaluating Web Sites for Accessibility Suite, particularly Conformance Evaluation of Web Sites for Accessibility
- Evaluating to Identify the Issues section of Improving the Accessibility of Your Web Site
- [WCAG 2.0 Quick Reference]
- [Understanding WCAG 2.0]
Step 5. Plan and Implement Changes to Your Site
Resources:
- [WCAG 2.0 Quick Reference]
- [Techniques for WCAG 2.0]
- [Understanding WCAG 2.0]
- Implementation Plan for Web Accessibility
- Optimizing Your Retrofitting section and Prioritizing the Repairs section of Improving the Accessibility of Your Web Site
Step 6. Update Internal Guidance
[changelog: Consider if any of the information from 4 and 5 is relevant.]
Resource: Techniques for WCAG 2.0
Update your internal Web development templates, guidance, [styles guides], processes, and such, based on the changes you made when updating your site to WCAG 2.0. For example, [@@??].
Periodically check if there are new techniques and best practices that you want to incorporate into your internal guidance. While the WCAG 2.0 technical standard itself is a stable document that will not change once it is completed, the Techniques for WCAG 2.0 is a supporting resource that can be updated. As technology develops, it will be [updated|enhanced] with additional tips, techniques, and best practices.
When Techniques for WCAG 2.0 is updated, we will announce it on the WAI home page and the WAI Interest Group (IG) mailing list. To get WAI announcements, you can subscribe to the following: