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[Draft] WCAG 2.0 Quick Reference

A customizable list of WCAG 2.0 requirements (success criteria) and techniques

Introduction

See the Overview of WCAG 2.0 Documents for an introduction to Web Content Accessibility Guidelines (WCAG) 2.0 and supporting documents.

This Quick Reference is based on the 17 May 2007 WCAG 2.0 draft. It lists all of the requirements (called "success criteria") in WCAG 2.0, along with techniques to meet the requirements. You can customize this Quick Reference to list only the information that you are interested in.

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  • The [Understanding Guideline x] and [Understanding Success Criterion x.x.x] links take you to the relevant section of the Understanding WCAG 2.0 document, which explains the intent of the guidelines and success criteria; provides examples and techniques; and describes how they help people with different disabilities.

Note that all techniques are informative. The "sufficient techniques" listed below are considered sufficient by the WCAG Working Group to meet the success criteria. However, it is not necessary to use these particular techniques. If techniques are used other than those listed by the Working Group, then some other method for establishing the technique's ability to meet the success criteria would be needed. In addition to the 'sufficient techniques', there are also advisory techniques that go beyond WCAG 2.0's requirements. Even content that completely conforms to WCAG will not be fully accessible to every person with a disability, especially people with language, learning, and cognitive disabilities, or multiple severe disabilities. Anyone can submit new techniques to the Working Group at any time. Please see Important New Terms Used in WCAG 2.0 for more information about sufficient techniques and advisory techniques.

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Table of Contents

WCAG 2.0 Quick Reference

Guideline 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 Understanding Guideline 1.1

1.1.1 Non-text Content: All non-text content has a text alternative that presents equivalent information, except for the situations listed below. (Level A)Understanding Success Criterion 1.1.1

  • Controls-Input: If non-text content is a control or accepts user input, then it has a name that describes its purpose. (See also Guideline 4.1.)

  • Media, Test, Sensory: If non-text content is multimedia , live audio-only or live video-only content, a test or exercise that must be presented in non-text format , or primarily intended to create a specific sensory experience , then text alternatives at least identify the non-text content with a descriptive text label. (For multimedia, see also Guideline 1.2.)

  • CAPTCHA: If the purpose of 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 in different modalities are provided to accommodate different disabilities.

  • Decoration, Formatting, Invisible: If non-text content is pure decoration, or used only for visual formatting, or if it is not presented to users, then it is implemented such that it can be ignored by assistive technology.

Sufficient Techniques for 1.1.1 (for the technologies you checked above)
Situation A: If a short description can serve the same purpose and present the same information as the non-text content:

  1. G94: Providing short text alternative for non-text content that serves the same purpose and presents the same information as the non-text content using a short text alternative technique listed below

Situation B: If a short description can not serve the same purpose and present the same information as the non-text content (e.g. a chart or diagram):

  1. G95: Providing short text alternatives that provide a brief description of the non-text content using a short text alternative technique listed below AND one of the following techniques for long description:

Situation C: If non-text content is a control or accepts user input:

  1. G82: Providing a text alternative that identifies the purpose of the non-text content using a short text alternative technique listed below

  2. Using HTML form controls and links (future link)

  3. H44: Using label elements to associate text labels with form controls (HTML)

  4. H65: Using the title attribute to identify form controls when the label element cannot be used (HTML)

  5. Using (X)HTML according to spec (future link)

Situation D: If non-text content is multimedia; live audio-only or live video-only content; a test or exercise that must use a particular sense; or primarily intended to create a specific sensory experience:

  1. Providing a descriptive label using a short text alternative technique listed below

  2. G68: Providing a descriptive label that describes the purpose of live audio-only and live video-only content using a short text alternative technique listed below

  3. G100: Providing the accepted name or a descriptive name of the non-text content using a short text alternative technique listed below

Situation E: If non-text content is a CAPTCHA:

  1. G143: Providing a text alternative that describes the purpose of the CAPTCHA AND G144: Ensuring that the Web Page contains another CAPTCHA serving the same purpose using a different modality

Situation F: If the non-text content should be ignored by assistive technology:

  1. Implementing or marking the non-text content so that it will be ignored by assistive technology using one of the technology-specific techniques listed below

Short text alternative techniques for use in sufficient techniques above
Long text alternative techniques for use in sufficient techniques above
Common Failures for 1.1.1
Advisory Techniques for 1.1.1
General Techniques for Informative Non-Text Content (Advisory)

  • Identifying informative non-text content (future link)

  • Keeping short descriptions short (future link)

  • Describing images that include text (future link)

  • Providing a longer description of the non-text content where only a descriptive label is required using a technology-specific technique (for an accessibility-supported content technology) for long description listed above (future link)

General Techniques for Live Non-Text Content (Advisory)

  • Linking to textual information that provides comparable information (e.g. for a traffic Webcam, a municipality could provide a link to the text traffic report.) (future link)

  • Providing a transcript of a live audio only presentation after the fact (future link)

HTML Techniques (Advisory)

  • H46: Using noembed with embed (HTML)

  • Writing for browsers that do not support frame (future link)

  • Providing alternative content for iframe (future link)

  • Providing text and non-text alternatives for object (future link)

  • Not using long descriptions for iframe (future link)

  • Providing redundant text links for client-side image maps (future link)

CSS Techniques (Advisory)

  • Using CSS margin and padding rules instead of spacer images (future link)

  • Using CSS background, :before or :after rules for decorative images instead of img elements (future link)

  • Displaying empty table cells (future link)

Guideline 1.2: Provide synchronized alternatives for multimedia Understanding Guideline 1.2

1.2.1 Captions (Prerecorded): Captions are provided for prerecorded multimedia, except for multimedia alternatives to text that are clearly labeled as such. (Level A)Understanding Success Criterion 1.2.1

Sufficient Techniques for 1.2.1 (for the technologies you checked above)

  1. G93: Providing open (always visible) captions

  2. G87: Providing closed captions using any readily available media format that has a video player that supports closed captioning

  3. G87: Providing closed captions using any of the technology-specific techniques below

Common Failures for 1.2.1
Advisory Techniques for 1.2.1

  • Providing a note saying "No sound is used in this clip" for video-only clips (future link)

  • Using SMIL 1.0 to provide captions for all languages for which there are audio tracks (future link)

  • Using SMIL 2.0 to provide captions for all languages for which there are audio tracks (future link)

1.2.2 Audio Description or Full Text Alternative: Audio description of video, or a full text alternative for multimedia including any interaction , is provided for prerecorded multimedia. (Level A)Understanding Success Criterion 1.2.2

Note: For 1.2.2, 1.2.4, and 1.2.7, if all of the information in the video track is already provided in the audio track, no audio description is necessary.

Sufficient Techniques for 1.2.2 (for the technologies you checked above)

  1. G69: Providing a full multimedia text alternative including any interaction

  2. G78: Providing a sound track that includes audio description as the primary sound track

  3. G78: Providing a sound track that includes audio description AND associating it with the multimedia content using one of the following techniques:

  4. Providing audio description in its own sound track (future link) AND merging the description track with the original soundtrack of the multimedia content at runtime using one of the following techniques

    • Using SMIL 1.0 to merge a description track with sound track (future link)

    • Using SMIL 2.0 to merge a description track with sound track (future link)

Advisory Techniques for 1.2.2

  • Providing audio description in multiple languages in SMIL 1.0 (future link)

  • Providing audio description in multiple languages in SMIL 2.0 (future link)

1.2.3 Captions (Live): Captions are provided for live multimedia. (Level AA)Understanding Success Criterion 1.2.3

Note: If multimedia is completely computer generated, it is not live and is subject to the requirements for pre-recorded multimedia in WCAG 2.0.

Sufficient Techniques for 1.2.3 (for the technologies you checked above)

  1. G9: Creating captions for live multimedia AND G93: Providing open (always visible) captions

  2. G9: Creating captions for live multimedia AND G87: Providing closed captions using any readily available media format that has a video player that supports closed captioning

  3. G9: Creating captions for live multimedia AND G87: Providing closed captions using one of the following techniques:

Note: Captions may be generated using real-time text translation service.

1.2.4 Audio Description: Audio description of video is provided for prerecorded multimedia. (Level AA)Understanding Success Criterion 1.2.4

Sufficient Techniques for 1.2.4 (for the technologies you checked above)

  1. G78: Providing a sound track that includes audio description as the primary sound track

  2. G78: Providing a sound track that includes audio description AND associating it with the multimedia content using one of the following techniques:

  3. Providing audio description in its own sound track (future link) AND merging the description track with the original soundtrack of the multimedia content at runtime using one of the following techniques

    • Using SMIL 1.0 to merge a description track with sound track (future link)

    • Using SMIL 2.0 to merge a description track with sound track (future link)

Advisory Techniques for 1.2.4

  • Providing audio description in multiple languages in SMIL 1.0 (future link)

  • Providing audio description in multiple languages in SMIL 2.0 (future link)

Sufficient Techniques for 1.2.5 (for the technologies you checked above)

  1. G54: Including a sign language interpreter in the video stream

  2. Providing a new page that has the video with the sign language interpretation of the audio track (future link)

  3. G81: Providing a synchronized video of the sign language interpreter that can be displayed in a different viewport or overlaid on the image by the player using one of the following techniques

1.2.6 Audio Description (Extended): Extended audio description of video is provided for prerecorded multimedia. (Level AAA)Understanding Success Criterion 1.2.6

Sufficient Techniques for 1.2.6 (for the technologies you checked above)

  1. Providing a second version of the movie with extended audio descriptions during halted video segments (future link)

  2. G8: Creating an extended audio description for the multimedia content using one of the following techniques

Advisory Techniques for 1.2.6

  • Adding extended audio description in multiple languages in SMIL 1.0 (future link)

  • Adding extended audio description in multiple languages in SMIL 2.0 (future link)

1.2.7 Full Text Alternative: A full text alternative for multimedia including any interaction is provided for all prerecorded multimedia , except for multimedia alternatives to text that are clearly labeled as such . (Level AAA)Understanding Success Criterion 1.2.7

Sufficient Techniques for 1.2.7 (for the technologies you checked above)

  1. G69: Providing a full multimedia text alternative including any interaction using one of the following techniques

Advisory Techniques for 1.2.7

Guideline 1.3: Create content that can be presented in different ways (for example spoken aloud, simpler layout, etc.) without losing information or structure Understanding Guideline 1.3

1.3.1 Info and Relationships: Information and relationships conveyed through presentation can be programmatically determined or are available in text , and notification of changes to these is available to user agents, including assistive technologies. (Level A)Understanding Success Criterion 1.3.1

Sufficient Techniques for 1.3.1 (for the technologies you checked above)
Situation A: The technology provides semantic structure to make information and relationships conveyed through presentation programmatically determinable:

  1. G115: Using semantic elements to mark up structure AND H49: Using semantic markup to mark emphasized or special text (HTML)

  2. G117: Using text to convey information that is conveyed by variations in presentation of text

  3. Separating information and structure from presentation to enable modification of presentation without altering content (future link)

  4. Making information and relationships conveyed through presentation programmatically determinable using the following techniques:

Situation B: The technology in use does NOT provide the semantic structure to make the information and relationships conveyed through presentation programmatically determinable:

  1. G117: Using text to convey information that is conveyed by variations in presentation of text

  2. Making information and relationships conveyed through presentation programmatically determinable or available in text using the following techniques:

Common Failures for 1.3.1
Advisory Techniques for 1.3.1

1.3.2 Meaningful Sequence: When the sequence in which content is presented affects its meaning, a correct reading sequence can be programmatically determined and sequential navigation of interactive components is consistent with that sequence. (Level A)Understanding Success Criterion 1.3.2

Sufficient Techniques for 1.3.2 (for the technologies you checked above)

  1. G57: Ordering the content in a meaningful sequence for all the content in the Web page

  2. Marking sequences in the content as meaningful using one of the following techniques AND G57: Ordering the content in a meaningful sequence for those sequences

Common Failures for 1.3.2
Advisory Techniques for 1.3.2

  • Using left-justified text for languages that are written left to right and right-justified text for languages that are written right-to-left (future link)

  • Using appropriate justification for languages that are written right-to-left (future link)

  • Providing a link to linearized rendering (future link)

  • Providing a style switcher between style sheets that affect presentation order (future link)

1.3.3 Size, Shape, Location: Instructions provided for understanding and operating content do not rely on shape, size, visual location, or orientation of components. (Level A)Understanding Success Criterion 1.3.3

Sufficient Techniques for 1.3.3 (for the technologies you checked above)

  1. G96: Providing textual identification of items that otherwise rely only on shape and/or position to be understood

Common Failures for 1.3.3
Advisory Techniques for 1.3.3

  • Using an image with a text alternative for graphical symbols instead of a Unicode font glyph with the desired graphical appearance but different meaning (future link)

Guideline 1.4: Make it easier for people with disabilities to see and hear content including separating foreground from background Understanding Guideline 1.4

1.4.1 Use of Color: Any information that is conveyed by color differences is also simultaneously visually evident without the color differences. (Level A)Understanding Success Criterion 1.4.1

Sufficient Techniques for 1.4.1 (for the technologies you checked above)
Situation A: If the color of particular words is used to indicate information:

  1. G14: Ensuring that color-encoded information is also available in text

  2. G122: Including a text cue whenever color cues are used

  3. Ensuring that when text color is used to convey information, the text style is visually differentiated without color (future link)

Situation B: If color is used within an image to convey information:

  1. G111: Using color and pattern

  2. G14: Ensuring that color-encoded information is also available in text

Common Failures for 1.4.1
Advisory Techniques for 1.4.1

  • Conveying information redundantly using color (future link)

  • Changing the background color or border of the element with focus (future link)

1.4.2 Audio Turnoff: If any audio plays automatically for more than 3 seconds, either a mechanism is available to pause or stop the audio, or a mechanism is available to control audio volume which can be set independently of the system volume. (Level A)Understanding Success Criterion 1.4.2

Sufficient Techniques for 1.4.2 (for the technologies you checked above)

  1. G60: Playing a sound that turns off automatically within three seconds

  2. Playing sounds only on user request (future link)

  3. Providing a control near the top of the Web page that turns off sounds that play automatically (future link)

  4. Providing a user interface control to pause or stop multimedia (future link)

Common Failures for 1.4.2
Advisory Techniques for 1.4.2

  • Providing a sitewide preference to turn off audio in addition to providing a control near the top of the Web page that turns off sounds that play automatically (future link)

1.4.3 Contrast (Minimum): Text (and images of text) have a contrast ratio of at least 5:1, except if the text is pure decoration. Larger-scale text or images of text can have a contrast ratio of 3:1. (Level AA)Understanding Success Criterion 1.4.3

Sufficient Techniques for 1.4.3 (for the technologies you checked above)
Situation A: text is less than 18 point if not bold and less than 14 point if bold

  1. G18: Ensuring that a contrast ratio of at least 5:1 exists between text and background behind the text

  2. H21: Not specifying background color, not specifying text color, and not using CSS that changes those defaults (HTML)

Situation B: text is as least 18 point if not bold and at least 14 point if bold

  1. G145: Ensuring that a contrast ratio of at least 3:1 exists between text and background behind the text

  2. H21: Not specifying background color, not specifying text color, and not using CSS that changes those defaults (HTML)

Common Failures for 1.4.3
Advisory Techniques for 1.4.3

  • Using a higher contrast value for text that is over a patterned background (future link)

  • Creating foreground and background contrast (future link)

  • Using a light pastel background rather than a white background behind black text (future link)

  • Using Unicode text and style sheets instead of images of text (future link)

  • Using a higher contrast values for lines in diagrams (future link)

  • Using greater contrast level for red-black text/background combinations

  • Using colors that are composed predominantly of mid spectral components for the light and spectral extremes (blue and red wavelengths) for the dark

1.4.4 Resize text: Visually rendered text can be resized without assistive technology up to 200 percent and down to 50 percent without loss of content or functionality. (Level AA)Understanding Success Criterion 1.4.4

Sufficient Techniques for 1.4.4 (for the technologies you checked above)

  1. G142: Using a technology that has commonly-available user agents that support zoom

  2. Ensuring that text containers resize when the text resizes AND using measurements that are relative to other measurements in the content by using one or more of the following techniques:

  3. Providing controls on the Web page that incrementally change the size of the text (future link)

  4. Providing options within the content to switch between layouts that use a variety of font sizes (future link)

Common Failures for 1.4.4
Advisory Techniques for 1.4.4

  • Providing large fonts by default (future link)

  • Avoiding the use of text in raster images (future link)

  • Using page-percent for container sizes (future link)

  • Avoiding scaling font sizes smaller than the user-agent default (future link)

    Note: The author won't actually know the font size, but should avoid percentage scaling that results in less than 100%

  • Avoiding justified text (future link)

  • Providing sufficient inter-line and inter-column spacing (future link)

1.4.5 Contrast (Enhanced): Text (and images of text) have a contrast ratio of at least 7:1, except if the text is pure decoration. Larger-scale text or images of text can have a contrast ratio of 5:1. (Level AAA)Understanding Success Criterion 1.4.5

Sufficient Techniques for 1.4.5 (for the technologies you checked above)
Situation A: text is less than 18 point if not bold and less than 14 point if bold

  1. G17: Ensuring that a contrast ratio of at least 7:1 exists between text and background behind the text

  2. H21: Not specifying background color, not specifying text color, and not using CSS that changes those defaults (HTML)

Situation B: text is as least 18 point if not bold and at least 14 point if bold

  1. G18: Ensuring that a contrast ratio of at least 5:1 exists between text and background behind the text

  2. H21: Not specifying background color, not specifying text color, and not using CSS that changes those defaults (HTML)

Common Failures for 1.4.5
Advisory Techniques for 1.4.5

  • Using a higher contrast value for text that is over a patterned background (future link)

  • Using Unicode text and style sheets instead of images of text (future link)

  • Using a light pastel background rather than a white background behind black text (future link)

  • Using a higher contrast values for lines in diagrams (future link)

  • Using greater contrast level for red-black text/background combinations

  • Using colors that are composed predominantly of mid spectral components for the light and spectral extremes (blue and red wavelengths) for the dark

1.4.6 Low or No Background Audio: Audio content that contains speech in the foreground does not contain background sounds, background sounds can be turned off, or background sounds are at least 20 decibels lower than the foreground speech content, with the exception of occasional sound effects. (Level AAA)Understanding Success Criterion 1.4.6

Note: Background sound that meets this requirement will be approximately one quarter as loud as the foreground speech content.

Sufficient Techniques for 1.4.6 (for the technologies you checked above)

  1. G56: Mixing audio files so that non-speech sounds are at least 20 decibels lower than the speech audio content

  2. Not including audio content (future link)

Advisory Techniques for 1.4.6

  • Providing a way for users to adjust auditory levels of foreground and background sound independently (future link)

1.4.7 Resize and Wrap: Visually rendered text can be resized without assistive technology up to 200 percent and down to 50 percent without loss of content or functionality and in a way that does not require the user to scroll horizontally. (Level AAA)Understanding Success Criterion 1.4.7

Sufficient Techniques for 1.4.7 (for the technologies you checked above)

  1. G146: Using liquid layout AND ensuring that text containers resize when the text resizes AND using measurements that are relative to other measurements in the content by using one or more of the following techniques:

  2. Providing options within the content to switch between layouts that use a variety of font sizes (future link)

  3. Using single-column layouts (future link)

Common Failures for 1.4.7
Advisory Techniques for 1.4.7

  • Providing large fonts by default (future link)

  • Avoiding the use of text in raster images (future link)

  • Using page-percent for container sizes (future link)

  • Avoiding scaling font sizes smaller than the user-agent default (future link)

    Note: The author won't actually know the font size, but should avoid percentage scaling that results in less than 100%

  • Avoiding justified text (future link)

  • Providing sufficient inter-line and inter-column spacing (future link)

Guideline 2.1: Make all functionality available from a keyboard Understanding Guideline 2.1

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)Understanding Success Criterion 2.1.1

Note 1: This exception relates to the underlying function, not the input technique. For example, if using handwriting to enter text, the input technique (handwriting) requires path dependent input but the underlying function (text input) does not.

Note 2: This does not forbid and should not discourage providing mouse input or other input methods in addition to keyboard operation.

Sufficient Techniques for 2.1.1 (for the technologies you checked above)

  1. G21: Ensuring that users are not trapped in content AND ensuring keyboard control by using one of the following techniques.

    • Using HTML form controls and links (future link)

  2. G21: Ensuring that users are not trapped in content AND G90: Providing keyboard-triggered event handlers using one of the following techniques:

Common Failures for 2.1.1
Advisory Techniques for 2.1.1

  • Providing keyboard access to important links and form controls (future link)

  • Using unique letter combinations to begin each item of a list (future link)

  • Choosing the most abstract event handler (future link)

  • Using the onactivate event (future link)

  • Avoiding use of common user-agent keyboard commands for other purposes (future link)

2.1.2 Keyboard (No Exception): All functionality of the content is operable through a keyboard interface without requiring specific timings for individual keystrokes. (Level AAA)Understanding Success Criterion 2.1.2

Sufficient Techniques for 2.1.2 (for the technologies you checked above)

  1. No additional techniques exist for this Success Criterion. Follow techniques for Success Criterion 2.1.1. If that is not possible because there is a requirement for analog, time-dependent input, then it is not possible to meet this Level AAA Success Criterion.

Guideline 2.2: Provide users with disabilities enough time to read and use content Understanding Guideline 2.2

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

  • 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, "hit any key"), 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 part of an activity where timing is essential (for example, time-based testing) and time limits can not be extended further without invalidating the activity.

Sufficient Techniques for 2.2.1 (for the technologies you checked above)
Situation A: If there are session time limits:

  1. G133: Providing a checkbox on the first page of a multipart form that allows users to ask for longer session time limit or no session time limit

Situation B: If a time limit is controlled by a script on the page:

  1. Providing a way for the user to turn the time limit off (future link)

  2. Providing the user with a means to set the time limit to 10 times the default time limit (future link)

  3. SCR16: Providing a script that warns the user a time limit is about to expire (Scripting) AND SCR1: Allowing the user to extend the default time limit (Scripting)

Common Failures for 2.2.1
Advisory Techniques for 2.2.1

  • Using a script to poll the server and notify a user if a time limit is present (future link)

  1. G11: Creating content that blinks for less than 3 seconds

  2. Using a technology to include blinking content that can be turned off via the user agent (future link)

  3. Using a control in the Web page that stops blinking content (future link) using one of the following techniques:

  • Providing a mechanism to stop all content that blinks within a Web page (future link)

  • Providing the user with a means to stop moving content even if it stops automatically within 3 seconds (future link)

2.2.3 Pausing: Moving, blinking, scrolling, or auto-updating information can be paused by the user unless it is part of an activity where timing or movement is essential. Moving content that is pure decoration can be stopped by the user. (Level AA)Understanding Success Criterion 2.2.3

Sufficient Techniques for 2.2.3 (for the technologies you checked above)

  1. G4: Allowing the content to be paused and restarted from where it was stopped

  2. Using script to scroll content, and providing a mechanism to pause it (future link)

  3. Allowing purely decorative content to be stopped (future link)

Common Failures for 2.2.3

2.2.4 Timing: Timing is not an essential part of the event or activity presented by the content, except for non-interactive multimedia and real-time events. (Level AAA)Understanding Success Criterion 2.2.4

Sufficient Techniques for 2.2.4 (for the technologies you checked above)

  1. G5: Allowing users to complete an activity without any time limit

2.2.5 Interruptions: Interruptions, such as updated content, can be postponed or suppressed by the user, except interruptions involving an emergency. (Level AAA)Understanding Success Criterion 2.2.5

Sufficient Techniques for 2.2.5 (for the technologies you checked above)

  1. G75: Providing a mechanism to postpone any updating of content

  2. Allowing users to request updates instead of automatically updating content (future link)

  3. SCR14: Using scripts to make nonessential alerts optional (Scripting)

Common Failures for 2.2.5

2.2.6 Re-authenticating: When an authenticated session expires, the user can continue the activity without loss of data after re-authenticating. (Level AAA)Understanding Success Criterion 2.2.6

Sufficient Techniques for 2.2.6 (for the technologies you checked above)

  1. Providing options to continue without loss of data using one of the following techniques:

Note: Refer to Techniques for Addressing Success Criterion 2.2.1 for techniques related to providing notifications about time limits.

Common Failures for 2.2.6

Guideline 2.3: Do not create content that is known to cause seizures Understanding Guideline 2.3

2.3.1 Three Flashes or Below Threshold: Content does 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)Understanding Success Criterion 2.3.1

Sufficient Techniques for 2.3.1 (for the technologies you checked above)
Situation A: Web content server over the Internet for general viewing

  1. Using all possible 341 x 256 pixel rectangles on 1024 x 768 pixel display to represent a 10 degree field of view at normal viewing distance AND G15: Ensuring that content does not violate the general flash threshold or red flash threshold

    Note: There is a tool that is available to carry out this test.

  2. G19: Ensuring that no component of the content flashes more than three times in any 1-second period

Situation B: Web content designed for a specific large-scale display where size and viewing distance is known

  1. Using actual viewing distance to calculate a 10 degree field of view in pixels AND G15: Ensuring that content does not violate the general flash threshold or red flash threshold

    Note: There is a tool that is available to carry out this test.

  2. G19: Ensuring that no component of the content flashes more than three times in any 1-second period

Advisory Techniques for 2.3.1

  • Reducing contrast for any flashing content (future link)

  • Avoiding fully saturated reds for any flashing content (future link)

  • Reducing the number of flashes even if they do not violate thresholds (future link)

  • Providing a mechanism to suppress any flashing content before it begins (future link)

2.3.2 Three Flashes: Content does not contain anything that flashes more than three times in any one second period. (Level AAA)Understanding Success Criterion 2.3.2

Sufficient Techniques for 2.3.2 (for the technologies you checked above)

  1. G19: Ensuring that no component of the content flashes more than three times in any 1-second period

Advisory Techniques for 2.3.2

  • Reducing contrast for any flashing content (future link)

  • Avoiding fully saturated reds for any flashing content (future link)

  • Reducing the number of flashes even if they don't violate thresholds (future link)

  1. Creating links to skip blocks of repeated material using one of the following techniques:

  2. Grouping blocks of repeated material in a way that can be skipped, using one of the following techniques:

  1. G88: Providing descriptive titles for Web pages AND associating a title with a Web page using one of the following techniques:

  1. G59: Placing the interactive elements in an order that follows sequences and relationships within the content

  2. Giving focus to elements in an order that follows sequences and relationships within the content using one of the following techniques:

  1. G91: Providing link text that describes the purpose of a link

  2. G53: Identifying the purpose of a link using link text combined with the text of the enclosing sentence

  3. Providing a supplemental description of the purpose of a link using one of the following techniques:

  4. Identifying the purpose of a link using link text combined with programmatically determined link context using one of the following techniques:

  1. Using two or more of the following techniques:

  1. G130: Providing descriptive headings