Mapping Section 508 to WCAG 2.0

Wayne Dick and Tom Jewett

This is a summary of a presentation that we gave at the 2009 International Conference on Technology and Persons with Disabilities (CSUN), titled “How to Use W3C Guidelines to Achieve Legally Compliant Web Sites.” Also contained here, but not presented in that talk, is a listing of the suggested WCAG 2.0 techniques for each of the Section 508 paragraphs 1194.22 (a)–(p).

Introduction

At first glance, the new World-Wide Web Consortium (W3C) Web Content Accessibility Guidelines (WCAG) 2.0 may seem to be “just more work” for developers who believe that they are “only required” to meet legal standards such as Section 508 of the (United States) Rehabilitation Act. Fortunately, this is not the case. In fact, after carefully mapping Section 508 to WCAG 2.0, we believe that the two documents compliment each other:

The mapping strategy

We will illustrate our six-step process with the first criterion of Section 508, paragraph 1194.22 (a): “A text equivalent for every non-text element shall be provided (for example via alt or longdesc attributes, or in element content).”

  1. We state the need for this criterion: “Non textual information like pictures, graphs or charts cannot be perceived by many users. Assistive technology cannot identify a non-text element or recognize the meaning of a non-text element without textual content to describe it.”
  2. We identify what is needed for “equally effective access” under the criterion: “Text must be provided for non-text elements so that the identity and meaning can be conveyed by assistive technology in a mode that the user can perceive.”
  3. Now referencing WCAG 2.0, we identify one or more of the four principles (perceivable, operable, understandable, robust) that apply to this criterion; in this case Principle 1, Perceivable.
  4. From here, we follow the WCAG 2.0 structure to identify which guidelines apply to this criterion; in this case Guidelines 1.1, Text Alternatives and Guideline 1.3, Adaptable.
  5. We find that there are two success criteria in WCAG 2.0 that relate to the applicable guidelines: 1.1.1, Non-Text Content, and 1.3.3, Sensory Characteristics.
  6. Finally, we move from the normative portion of the WCAG to identify the specific sufficient techniques that developers may use to insure that their work is as accessible as it can be made with current technology.

The complete mapping of each Section 508 paragraph 1194.22 guideline in this form, excluding the techniques, was first developed by Wayne Dick in a paper entitled “Mapping Section 508 to WCAG 2.0 Level A.” (no longer on line)

Suggested techniques

The WCAG 2.0 techniques listed here represent only the authors' suggestions for each 508 checkpoint; they are re-arranged and in many cases paraphrased from the original documents. For each technique, the corresponding success criterion is listed in parentheses, e.g., (1.1.1), and linked to its description in the official W3C Recommendation. Please also see the W3C's How to Meet WCAG 2.0 page for detailed information on these and many more useful techniques.

Text alternatives

1194.22 (a) A text equivalent for every non-text element shall be provided (for example via alt or longdesc attributes, or in element content)

Multimedia

1194.22 (b) Equivalent alternatives for any multimedia presentation shall be synchronized with the presentation.

Color

1194.22 (c) Web pages shall be designed so that all information conveyed with color is also available without color, for example from context or markup.

Style sheets

1194.22 (d) Documents shall be organized so they are readable without requiring an associated style sheet.

Server-side image maps

1194.22 (e) Redundant text links shall be provided for each active region of a server-side image map.

Client-side image maps

1194.22 (f) Client-side image maps shall be provided instead of server-side image maps except where the regions cannot be defined with an available geometric shape.

Simple data tables

1194.22 (g) Row and column headers shall be identified for data tables.

Complex data tables

1194.22 (h) Markup shall be used to associate data cells and header cells for data tables that have two or more logical levels of row or column headers.

Frames

1194.22 (i) Frames shall be titled with text that facilitates frame identification and navigation.

Flicker

1194.22 (j) Pages shall be designed to avoid causing the screen to flicker with a frequency greater than 2 Hz and lower than 55 Hz.

Text-only

1194.22 (k) A text-only page, with equivalent information or functionality, shall be provided to make a web site comply with the provisions of this part, when compliance cannot be accomplished in any other way. The content of the text-only page shall be updated whenever the primary page changes.

Scripting

1194.22 (l) When pages utilize scripting languages to display content, or to create interface elements, the information provided by the script shall be identified with functional text that can be read by assistive technology.

Applets and plug-ins

1194.22 (m) When a web page requires that an applet, plug-in or other application be present on the client system to interpret page content, the page must provide a link to a plug-in or applet that complies with paragraphs 1194.21(a) through (l).

Forms

1194.22 (n) When electronic forms are designed to be completed on-line, the form shall allow people using assistive technology to access the information, field elements, and functionality required for completion and submission of the form, including all directions and cues.

Skip navigation

1194.22 (o) A method shall be provided that permits users to skip repetitive navigation links.

Timed response

1194.22 (p) When a timed response is required, the user shall be alerted and given sufficient time to indicate more time is required.

Strongly recommended

The following techniques have no specific counterpart in Section 508, but will complete a page's conformance with WCAG 2.0 Level A.