The Section 508 standard uses the exact language of WCAG 1.0 Checkpoint 1.1 without “This includes” of WCAG 1.1.

The picture is complicated by the role of such extensions to HTML in WCAG 1.0 compared to that in Section 508. For the former the pages must be usable with scripts and applets turned off or not supported. This makes the importance of the “text equivalent” much greater for WCAG compliance compared with Section 508. For section 508 these extensions must be accessible (see Paragraphs 1194.22 (l) and 1194.22 (m)). Jim Hatcher

WCAG 2.0 Guidline 1.1 clarifies the text equivalent issue over WCAG 1.1 in two ways.

1. It does not have a list of includes, leaving this guideline open to new technology.
2. It does include a list of excluded situations, but again leaves the specific technology open for future advances. The exclusions are:
   • Controls, Input: If non-text content is a control or accepts user input, then it has a name that describes its purpose. (Refer to Guideline 4.1 for additional requirements for controls and content that accepts user input.)
   • Time-Based Media: If non-text content is time-based media, then text alternatives at least provide descriptive identification of the non-text content. (Refer to Guideline 1.2 for additional requirements for media.)
   • Test: If non-text content is a test or exercise that would be invalid if presented in text, then text alternatives at least provide descriptive identification of the non-text content.
   • Sensory: If non-text content is primarily intended to create a specific sensory experience, then text alternatives at least provide descriptive identification of the non-text content.
   • CAPTCHA: If the purpose non-text content is to confirm that content is being accessed by a person rather than a computer, then text alternatives that identify and describe the purpose of the non-text content are provided, and alternative forms of CAPTCHA using output modes for different types of sensory perception are provided to accommodate different disabilities.
   • Decoration, Formatting, Invisible: If non-text content is pure decoration, is used only for visual formatting, or is not presented to users, then it is implemented in a way that it can be ignored by assistive technology.

Audio or Video Only

Generally covered in 1.4 but not specifically mentioned

1.2.1 Audio-only and Video-only (Prerecorded): For prerecorded audio-only and prerecorded video-only media, the following are true, except when the audio or video is a media alternative for text and is clearly labeled as such: (Level A)

• Prerecorded Audio-only: An alternative for time-based media is provided that presents equivalent information for prerecorded audio-only content.
• Prerecorded Video-only: Either an alternative for time-based media or an audio track is provided that presents equivalent information for prerecorded video-only content.

Not in Section 508 or WCAG 1

Generally covered in 1194.22 (b). but not specifically mentioned

Auditory description

1.3 Until user agents can automatically read aloud the text equivalent of a visual track, provide an auditory description of the important information of the visual track of a multimedia presentation.

1.2.3 An alternative for time-based media or audio description of the prerecorded video content is provided for synchronized media, except when the media is a media alternative for text and is clearly labeled as such. (Level A)

Not specifically in Section 508. WCAG 2 is more specific than WCAG 1

Generally covered in 1194.22 (b). but not specifically mentioned

Auditory description (prerecorded)

1.4 For any time-based multimedia presentation (e.g., a movie or animation), synchronize equivalent alternatives (e.g., captions or auditory descriptions of the visual track) with the presentation.

1.2.5 Audio Description (Prerecorded): Audio description is provided for all prerecorded video content in synchronized media. (Level AA)

Not specifically covered in Section 508 or WCAG 1

Generally covered in 1194.22 (b). but not specifically mentioned

Extended Audio Description (prerecorded)

Generally covered in 1.4 but not specifically mentioned

1.2.7 Extended Audio Description (Prerecorded): Where pauses in foreground audio are insufficient to allow audio descriptions to convey the sense of the video, extended audio description is provided for all prerecorded video content in synchronized media. (Level AAA)

Not specifically covered in Section 508 or WCAG 1

Generally covered in 1194.22 (b). but not specifically mentioned

Audio Only (Live)

Generally covered in 1.4 but not specifically mentioned

1.2.9 Audio-only (Live): An alternative for time-based media that presents equivalent information for live audio-only content is provided. (Level AAA)

Not specifically covered in Section 508 or WCAG 1

Generally covered in 1194.22 (b). but not specifically mentioned

Adaptable

Guideline 1.3 Create content that can be presented in different ways (for example simpler layout) without losing information or structure.

Not in Section 508 or WCAG 1

Meaningful Sequence

1.3.2 When the sequence in which content is presented affects its meaning, a correct reading sequence can be programmatically determined. (Level A)

Not in Section 508 or WCAG 1

The purpose of this guideline is to ensure that all information is available in a form that can be perceived by all users. For example, spoken aloud, or presented in a simpler visual layout . If all of the information is available in a form that can be determined by software, then it can be presented to users in different ways (visually, audibly, tactilely etc.). If information is embedded in a particular presentation in such a way that the structure and information cannot be programmatically determined by the assistive technology, then it cannot be rendered in other formats as needed by the user.

Guideline 1.3.1, while isn’t long or complex, replaces a significant amount of WCAG 1. WCAG 1 focused on the application of specific technology (eg. use of table headers and complex tables.) , while WCAG 2 lists general concepts and leaves the technology up to the developer.

Color

2.1 Ensure that all information conveyed with color is also available without color, for example from context or markup.

1.4.1 Use of Color: Color is not used as the only visual means of conveying information, indicating an action, prompting a response, or distinguishing a visual element. (Level A)

Very similar

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.

Minimum Contrast

2.2 Ensure that foreground and background color combinations provide sufficient contrast when viewed by someone having color deficits or when viewed on a black and white screen.

1.4.3 Contrast (Minimum): The visual presentation of text and images of text has a contrast ratio of at least 4.5:1, except for the following: (Level AA)

• Large Text: Large-scale text and images of large-scale text have a contrast ratio of at least 3:1;
• Incidental: Text or images of text that are part of an inactive user interface component, that are pure decoration, that are not visible to anyone, or that are part of a picture that contains significant other visual content, have no contrast requirement.
• Logotypes: Text that is part of a logo or brand name has no minimum contrast requirement

Not in Section 508. WCAG 1 and 2 are similar in intent, but WCAG 2 improves upon WCAG 1 by making identifying a specific testable ratio and by identifying exceptions to the rule.

Images of text

1.4.5 Images of Text: If the technologies being used can achieve the visual presentation, text is used to convey information rather than images of text except for the following: (Level AA)

• Customizable: The image of text can be visually customized to the user’s requirements;
• Essential: A particular presentation of text is essential to the information being conveyed.

Note: Logotypes (text that is part of a logo or brand name) are considered essential.

Not in Section 508 or WCAG 1

Low or no background audio

1.4.7 Low or No Background Audio: For prerecorded audio-only content that (1) contains primarily speech in the foreground, (2) is not an audio CAPTCHA or audio logo, and (3) is not vocalization intended to be primarily musical expression such as singing or rapping, at least one of the following is true: (Level AAA)

• No Background: The audio does not contain background sounds.
• Turn Off: The background sounds can be turned off.
• 20 dB: The background sounds are at least 20 decibels lower than the foreground speech content, with the exception of occasional sounds that last for only one or two seconds.Note: Per the definition of “decibel,” background sound that meets this requirement will be approximately four times quieter than the foreground speech content.

Not in Section 508 or WCAG 1

Images of Text

.

1.4.9 Images of Text (No Exception): Images of text are only used for pure decoration or where a particular presentation of text is essential to the information being conveyed. (Level AAA) Note: Logotypes (text that is part of a logo or brand name) are considered essential.

Not in Section 508 or WCAG 1

keyboard-only access

2.1.1 Keyboard: All functionality of the content is operable through a keyboard interface without requiring specific timings for individual keystrokes, except where the underlying function requires input that depends on the path of the user’s movement and not just the endpoints. (Level A)

Not in Section 508 or WCAG 1

Keyboard (No Exception)

2.1.3 Keyboard (No Exception): All functionality of the content is operable through a keyboard interface without requiring specific timings for individual keystrokes. (Level AAA)

Not in Section 508 or WCAG 1

Timing Adjustable

2.2.1 Timing Adjustable: For each time limit that is set by the content, at least one of the following is true: (Level A)

• Turn off: The user is allowed to turn off the time limit before encountering it; or
• Adjust: The user is allowed to adjust the time limit before encountering it over a wide range that is at least ten times the length of the default setting; or
• Extend: The user is warned before time expires and given at least 20 seconds to extend the time limit with a simple action (for example, “press the space bar”), and the user is allowed to extend the time limit at least ten times; or
• Real-time Exception: The time limit is a required part of a real-time event (for example, an auction), and no alternative to the time limit is possible; or
• Essential Exception: The time limit is essential and extending it would invalidate the activity; or
• 20 Hour Exception: The time limit is longer than 20 hours.

Not in Section 508 or WCAG 1

No timing

2.2.3 No Timing: Timing is not an essential part of the event or activity presented by the content, except for non-interactive synchronized media and real-time events. (Level AAA)

Not in Section 508 or WCAG 1

Re-authenticating

2.2.5 Re-authenticating: When an authenticated session expires, the user can continue the activity without loss of data after re-authenticating. (Level AAA)

Not in Section 508 or WCAG 1

Three flashes, below threshold

2.3.1 Three Flashes or Below Threshold: Web pages do not contain anything that flashes more than three times in any one second period, or the flash is below the general flash and red flash thresholds. (Level A)

Not in Section 508 or WCAG 1

clear navigation

Guideline 13. Provide clear navigation mechanisms.

Provide clear and consistent navigation mechanisms — orientation information, navigation bars, a site map, etc. — to increase the likelihood that a person will find what they are looking for at a site.

Guideline 2.4: Provide ways to help users navigate, find content, and determine where they are.

WCAG 1 and WCAG 2 are similar

Page title

Falls under the general category of Guideline 13. Provide clear navigation mechanisms, but has no specific mention of Page titles

2.4.2 Page Titled: Web pages have titles that describe topic or purpose. (Level A)

Not in Section 508 or specifically mentioned in WCAG 1

Link purpose

13.1 Clearly identify the target of each link. [Priority 2]

Link text should be meaningful enough to make sense when read out of context — either on its own or as part of a sequence of links. Link text should also be terse.

2.4.4 Link Purpose (In Context): The purpose of each link can be determined from the link text alone or from the link text together with its programmatically determined link context, except where the purpose of the link would be ambiguous to users in general. (Level A)

Not in Section 508. WCAG 1 and WCAG 2 are similar. WCAG 2 gives this a higher priority.

Headings and labels

2.4.6 Headings and Labels: Headings and labels describe topic or purpose. (Level AA)

Not in Section 508 or WCAG 1

Location

13.3 Provide information about the general layout of a site (e.g., a site map or table of contents). [Priority 2]

2.4.8 Location: Information about the user’s location within a set of Web pages is available. (Level AAA)

Not in Section 508. WCAG 1 suggests site information be available in the site, WCAG is more specific and requests location information be available on each page.

Section Headings

3.5 Use header elements to convey document structure and use them according to specification. [Priority 2]

For example, in HTML, use H2 to indicate a subsection of H1. Do not use headers for font effects.

2.4.10 Section Headings: Section headings are used to organize the content. (Level AAA)

Not in Section 508. WCAG 1 and WCAG 2 are similar.

Language of page

4.3 Identify the primary natural language of a document.. [Priority 1]

3.1.1 Language of Page: The default human language of each Web page can be programmatically determined. (Level A)

Not in Section 508. WCAG 1 and 2 are very similar.

Unusual words

4.2 Specify the expansion of each abbreviation or acronym in a document where it first occurs. [Priority 3]

3.1.3 Unusual Words: A mechanism is available for identifying specific definitions of words or phrases used in an unusual or restricted way, including idioms and jargon. (Level AAA)

Not in Section 508. WCAG 1 and 2 are somewhat similar, with WCAG 2 being more specific.

WCAG 1 is specific to one technology, while WCAG 2 is open to new technology.

Reading level

14.1 Use the clearest and simplest language appropriate for a site’s content. [Priority 1]

3.1.5 Reading Level: When text requires reading ability more advanced than the lower secondary education level after removal of proper names and titles, supplemental content, or a version that does not require reading ability more advanced than the lower secondary education level, is available. Level AAA)

Not in Section 508. WCAG 1 and 2 are somewhat similar, with WCAG 2 being more specific.

Predictable

Guideline 3.2: Make Web pages appear and operate in predictable ways.

Not in Section 508 or WCAG 1

On input

3.2.2 On Input: Changing the setting of any user interface component does not automatically cause a change of context unless the user has been advised of the behavior before using the component. (Level A)

Not in Section 508 or WCAG 1

Consistent identification

3.2.4 Consistent Identification: Components that have the same functionality within a set of Web pages are identified consistently. (Level AA)

Not in Section 508 or WCAG 1

Correct mistakes

Guideline 3.3: Help users avoid and correct mistakes.

Not in Section 508 or WCAG 1

Labels or Instructions

12.4 Associate labels explicitly with their controls. [Priority 2]

3.3.2 Labels or Instructions: Labels or instructions are provided when content requires user input. (Level A)

Not in Section 508. WCAG 2 is more specific than WCAG 1, and more open to advances in techniology.

Error Prevention (Legal, Financial, Data)

3.3.4 Error Prevention (Legal, Financial, Data): For Web pages that cause legal commitments or financial transactions for the user to occur, that modify or delete user-controllable data in data storage systems, or that submit user test responses, at least one of the following is true: (Level AA)

1. Reversible: Submissions are reversible.
2. Checked: Data entered by the user is checked for input errors and the user is provided an opportunity to correct them.
3. Confirmed: A mechanism is available for reviewing, confirming, and correcting information before finalizing the submission.

Not in Section 508 or WCAG 1

Error Prevention (All)

3.3.6 Error Prevention (All): For Web pages that require the user to submit information, at least one of the following is true: (Level AAA)

1. Reversible: Submissions are reversible.
2. Checked: Data entered by the user is checked for input errors and the user is provided an opportunity to correct them.
3. Confirmed: A mechanism is available for reviewing, confirming, and correcting information before finalizing the submission.

Not in Section 508 or WCAG 1

Parsing

3.2 Create documents that validate to published formal grammars. [Priority 2]

4.1.1 Parsing: In content implemented using markup languages, elements have complete start and end tags, elements are nested according to their specifications, elements do not contain duplicate attributes, and any IDs are unique, except where the specifications allow these features. (Level A)

Note:

• Avoiding deprecated features of W3C technologies (future link)
• Not displaying content that relies on technologies that are not accessibility-supported when the technology is turned off or not supported

Not in Section 508. WCAG 1 and WCAG 2 are similar, with WCAG 2 being more open to new technology, and being given a higher priority.