Principle 3: Understandable

3.0: Principle 3: Understandable

Information and the operation of user interface must be understandable

3.1 : Readable-Make text content readable and understandable

Advisory Techniques for Guideline 3.1

  • Setting expectations about content in the page from uncontrolled sources
  • Providing sign language interpretation for all content
  • Using the clearest and simplest language appropriate for the content

3.1.1: Language of Page: (A)

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

Sufficient Techniques for 3.1.1 – Language of Page

1.Identifying default human language(s) using one of the following techniques:

3.1.2: Language of Parts: (AA)

The human language of each passage or phrase in the content can be programmatically determined except for proper names, technical terms, words of indeterminate language, and words or phrases that have become part of the vernacular of the immediately surrounding text. (Level AA)

3.1.3: Unusual Words: (AAA)

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)

3.1.4: Abbreviations: (AAA)

A mechanism for identifying the expanded form or meaning of abbreviations is available. (Level AAA)

3.1.5: Reading Level: (AAA)

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)

3.1.6: Pronunciation: (AAA)

A mechanism is available for identifying specific pronunciation of words where meaning of the words, in context, is ambiguous without knowing the pronunciation. (Level AAA

3.2 : Make Web pages appear and operate in predictable ways

Advisory Techniques for Guideline 3.2

Positioning labels to maximize predictability of relationships.

3.2.1: On Focus: (A)

When any component receives focus, it does not initiate a change of context. (Level A)

Sufficient Techniques for 3.2.1 – On Focus

1.G107: Using “activate” rather than “focus” as a trigger for changes of context.

3.2.2: On Input: (A)

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)

3.2.3: Consistent Navigation: (AA)

Navigational mechanisms that are repeated on multiple Web pages within a set of Web pages occur in the same relative order each time they are repeated, unless a change is initiated by the user. (Level AA)

3.2.4: Consistent Identification: (AA)

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

3.2.5: Change on Request: (AAA)

Changes of context are initiated only by user request or a mechanism is available to turn off such changes. (Level AAA)

3.3 :Input Assistance:

Help users avoid and correct mistakes.

3.3.1: Error Identification: (A)

If an input error is automatically detected, the item that is in error is identified and the error is described to the user in text. (Level A)

3.3.2: Labels or Instructions: (A)

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

Sufficient Techniques for 3.3.2 – Labels or Instructions

  • 1.G131: Providing descriptive labels AND one of the following:

3.3.3: Error Suggestion: (AA)

If an input error is automatically detected and suggestions for correction are known, then the suggestions are provided to the user, unless it would jeopardize the security or purpose of the content. (Level AA)

3.3.4: Error Prevention (Legal, Financial, Data): (AA)

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)

3.3.5: Help: (AAA)

Context-sensitive help is available. (Level AAA)

Sufficient Techniques for 3.3.5 – Help

Situation A: If a form requires text input:

  • 1.G71: Providing a help link on every Web page

3.3.6:Error Prevention (All): (AAA)

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.