Web Content Accessibility Guidelines 2.0 -- View 5 - Best Practice and Additional Notes Only

Best Practice Measures for Checkpoint 1.1

1. non-text content that can not be expressed in words has a text equivalent for all aspects that can be expressed in words.

2. a text document that merges all audio descriptions and captions into a collated script (that provides dialog, important sounds and important visual information in a single text document) is provided.

Best Practice Measures for Checkpoint 1.2

1. Editorial Note: This whole Checkpoint (1.2) needs reworking. Perhaps move some down from above, or limit the items above to just certain classes of content - and then put the rest of the coverage (for other types of content) here.

2. captions and audio descriptions are provided for all live broadcasts.

3. the presentation does not require the user to read captions and the visual presentation simultaneously in order to understand the content.

Best Practice Measures for Checkpoint 1.3

1. any information presented using color is also available without color and without having to interpret markup.[I#317]

2. any blinking content can be turned off.[I#325]

Best Practice Measures for Checkpoint 1.4

1. abbreviations and acronyms are clearly identified each time they occur if they collide with a word in the standard language that would also logically appear in the same case (e.g. all caps). (See also checkpoint 3.1) [I#341]

2. symbols such as diacritic marks that are found in standard usage of the natural language of the content, and that are necessary for unambiguous identification of words, are present or another standard mechanism for disambiguation is provided.

Best Practice Measures for Checkpoint 1.5

1. the structural emphases are chosen to be distinct on different major visual display types (e.g. black and white, small display, mono audio playback).

2. Content is constructed such that users can control the presentation of structural elements or the emphasis on the structure can be varied through alternate presentation formats.

Additional Notes for Checkpoint 1.5 (Informative)

1. for visual presentations, font variations, styles, size and white space can be used to emphasize structure.

2. color and graphics can be used to emphasize structure.

3. for auditory presentations, different voice characteristics and/sounds can be used for major headings, sections and other structural elements.

4. if content is targeted for a specific user group and the presentation of the structured content is not salient enough to meet the needs of your audience, additional graphics, colors, sounds, and other aspects of presentation can be used to emphasize the structure.

Best Practice Measures for Checkpoint 1.6

1. when text content is presented over a background image or pattern, the text is easily readable when the page is viewed in 256 grayscale.

   Editorial Note: this item may be moved or updated if the proposal for adding an extended checkpoint on color is accepted.

2. this item should read identically to the required item #2, except that it should say "in default presentation mode."

Editorial Note: The working group is seeking an algorithm that measures contrast in a way that is accurate and testable enough that we could include it in the guidelines. One algorithm, which comes from the Techniques For Accessibility Evaluation And Repair Tools document, is currently under consideration for inclusion in the techniques, but the group has not yet found something that is specific enough to be included at the guidelines level.

Best Practice Measures for Checkpoint 1.8

1. content can be perceived with no color vision

Best Practice Measures for Checkpoint 2.1

1. wherever a choice between event handlers is available and supported, the more abstract event is used.

Best Practice Measures for Checkpoint 2.2

1. any moving content can be frozen using the keyboard[I#325]

Best Practice Measures for Checkpoint 2.3

1. animation or other content does not visibly or purposely flicker between 3 and 49 Hz.

2. content that might create a problem has been tested [using XYZ tool]; only pages with unavoidable flicker remain and appropriate warnings along with a close alternative presentation have been provided for these pages.

Best Practice Measures for Checkpoint 2.4

1. the content has been reviewed, taking into account the following strategies for facilitating orientation and movement, applying them as appropriate.

   1. breaking up text into logical paragraphs

   2. providing hierarchical sections and titles, particularly for longer documents

   3. revealing important non-hierarchical relationships, such as cross-references, or the correspondence between header and data cells in a table, so that they are represented unambiguously in the markup or data model

   4. dividing very large works into sections and or chapters with logical labels

   5. others?

2. information is provided that would allow an assistive technology to determine at least one logical, linear reading order.

3. diagrams are constructed in a fashion so that they have structure that can be accessed by the user.

4. where possible, logical tab order has been created.[I#319]

Best Practice Measures for Checkpoint 2.5

1. where possible, the user is allowed to select from a list of options as well as to generate input text directly

2. errors are identified specifically and suggestions for correction are provided where possible

3. checks for misspelled words are applied and correct spellings are suggested when text entry is required.

4. where consequences are significant and time-response is not important, one of the following is true

   1. actions are reversible

   2. where not reversible, actions are checked for errors in advance

   3. where not reversible, and not checkable, a confirmation is asked before acceptance

Best Practice Measures for Checkpoint 3.1

Best Practice Measures for Checkpoint 3.2

1. a list is provided on the page or home page of URIs to cascading dictionaries that can or should be used to define abbreviations or acronyms.[I#350]

2. the content has been reviewed, taking into account the following strategies for determining the definition of abbreviations and acronyms, applying them as appropriate.

   1. provide a definition or link (with the first occurrence) of phrases, words, acronyms, and abbreviations specific to a particular community.

   2. provide a summary for relationships that may not be obvious from analyzing the structure of a table but that may be apparent in a visual rendering of the table.

   3. if contracted forms of words are used such that they are ambiguous, provide semantic markup to make words unique and interpretable.

Best Practice Measures for Checkpoint 3.3

1. the content has been reviewed, taking into account the strategies for evaluating the complexity of the content, applying them as appropriate.

Additional Notes for Checkpoint 3.3 (Informative)

Strategies for evaluating the complexity of the content include:

1. use of sentence structures that increase understanding

   • such as active voice in languages where this form helps convey information

2. length of noun phrases

   • strings of no more than three or four nouns are easiest to understand

3. clarity of reference with pronouns and anaphoric expressions (these refer back to something already said in the text)

   • example of potential ambiguity: "Scientists study monkeys. They eat bananas."

4. correct use of conjunction forms and adverbs to make explicit the relationship between phrases or parts of the text

   • such as "and," "but," "furthermore," "not only"

5. complexity of verb tenses

   • do the tenses used in a document seem overly complicated?

6. intelligibility of verb phrases

7. familiarity of idioms or slang

8. logic in the order and flow of information

9. consequences of ambiguity or abstraction

10. improved readability of vertical lists might offer in place of long paragraphs of information

11. use of summaries to aid understanding

12. thoroughness in the explanation of instructions or required actions

13. consistency in the use of names and labels

14. clarity where the document:

    • addresses users

    • explains choices and options

    • labels options to get more information

    • instructs users how to modify selections in critical functions (such as how to delete an item from a shopping cart)

15. application of:

    • proper markup to highlight key information

    • goal-action structure for menu prompts

    • default settings (and the ease in re-establishing them)

    • two-step "select and confirm" processes to reduce accidental selections for critical functions

    • calculation assistance to reduce the need to calculate

16. testing with potential users for ease of accessibility

17. use of a controlled language

18. providing support for conversion into symbolic languages

19. adding non-text content to the site for key pages or sections specifically to make the site more understandable by users who cannot understand the text only version of the site.

Best Practice Measures for Checkpoint 3.4

1. user can select a different location for navigation elements in the layout of the page.[I#352]

2. the content has been reviewed, taking into account common ideas for making content consistent and predictable, applying them as appropriate.

Additional Notes for Checkpoint 3.4 (Informative)

1. common ideas for making content consistent and predictable indclude:

   1. place navigation bars in a consistent location whenever possible

   2. similar layout for user interface components should be used for sections or whole site

   3. similar user interface components should be labeled with similar terminology

   4. use headers consistently

   5. use templates for consistent presentation of sections or whole site

   6. pages with similar function should have similar appearance and layout

   7. controls that look or sound the same should be designed to act the same

   8. conventions likely to be familiar to the user should be followed

   9. unusual user interface features or behaviors that are likely to confuse the first-time user should be described to the user before they are encountered

   10. allow the user to select different page layout templates for presentation of pages. (e.g. 3 column, linear, adding extra orientation or navigation elements, etc.) [I#353]

Best Practice Measures for Checkpoint 4.1

1. Same as item #1 above, without the exception for backward compatibility.

Best Practice Measures for Checkpoint 4.2

1. accessibility conventions of the markup or programming language (API's or specific markup) are used [I#331]

2. the interface has been tested using a variety of assistive technologies and preferably real people with disabilities who use assistive technologies to determine that those assistive technologies are able to access all information on the page or hidden within the page.

Best Practice Measures for Checkpoint 4.3

1. a list of technologies and features, support for which is required in order for the content to be operable, has been determined and is documented in metadata and / or a policy statement associated with the content.

2. technologies and features on the required list are available in at least two independently-developed implementations. (it is preferable that the technologies used for the implementations have been supported for at least one prior version of the software)