Priority 1 / Level A

Submitted by Heinrich_Pick on Wed, 18/06/2008 - 17:15.

These are the requirements for Priority 1 / Level A:

Text Alternatives

  1. Controls, Input: If non-text content is a control or accepts user input, then it has a name that describes its purpose. Have a closer look at Buttons like a "send-button" informs or images /icons that indicate to start a function like a "search-icon" or link to an pdf staing "this lik will open the pdf".

  2. Pictures should have a short discription telling in one Sentance what is on the picture. In some cases it might be useful to have a longer discription, when the image is important to understand the text (but I suggest we do not try to achiev this)

  3. Charts (non-text only) need to have a short discription stating what this chart is about and a longer text telling what is in it.

  4. Charts (text) A table presents a list of times across the top row and a list of events in the first vertical column. The cell corresponding to the time of a particular event has a specific background color and diamond shaped glyph so it can be identified by color and shape.
  5. An on-line multi-page survey
    An on-line multi-page survey uses a link implemented as a green arrow icon placed in the lower right hand corner of the content to move from one survey page to the next. The arrow is clearly labeled with "Next" and the instructions state, "To move to the next section of the survey, select the green arrow icon labeled 'Next' in the lower right below the last survey question." This example uses both positioning, color and labeling to help identify the icon.
  6. Forms: An introducing text stating that a asterix indicates compulsory fields and, if so, are marked in (f.e.) red is recomended. Asteriks behind a field will determine by assistive technology. Also offer an programmatic assigned alternativ text or label to each field stating what is requiered and if compulsory (f.e. "required field first name").
    Espacially have a closer look how forms behave when the user try to sent/saved them with compulsory content missing. Are the missing content fields only indicated in red? Than we need to think about an alt-tag or label for this.

  7. CAPTCHA: provide text alternatives that identify and describe the purpose of the non-text content, and alternative forms of CAPTCHA using output modes for different types of sensory perception are provided to accommodate different disabilities.

    CAPTCHAs are a controversial topic in the accessibility community. .

    Because some users with disabilities will still not be able to access sites that meet the minimum requirements, the Working Group provides recommendations for additional steps. Organizations motivated to conform to WCAG should be aware of the importance of this topic and should go as far beyond the minimum requirements of the guidelines as possible. Additional recommended steps include:

    1. Providing more than two modalities of CAPTCHAs

    2. Providing access to a human customer service representative who can bypass CAPTCHA

    3. Not requiring CAPTCHAs for authorized users

  8. 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.

  9. Audio Control: If any audio on a Web page 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 independently from the overall system volume level.

  10. 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.

  11. No Keyboard Trap:If keyboard focus can be moved to a component of the page using a keyboard interface, then focus can be moved away from that component using only a keyboard interface, and, if it requires more than unmodified arrow or tab keys, the user is advised of the method for moving focus away. Example: A calendar widget allows users to add, remove or update items in their calendar using the keyboard. The controls in the widget are part of the tab order within the Web page, allowing users to tab through the controls in the widget as well as to any links or controls that follow.

  12. 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 >no alt-tag or empty alt-tag.

  13. Tests: If non-text content is a test or exercise that must be presented in non-text format, then text alternatives at least provide descriptive identification of the non-text content.

  14. 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. ...to be continued >>I suggest not to use non-text content to creat a specific sensory experience

Time Based Media
If we use Time based media such as video and audio this following is only relevant for Time based Media which is not an alternative to a text. >> If the TBM is off less relevance, as there is a text going with it, it can be labeled (labeling is important!) as such and we do not heve to do the following, if their is no text we do (podcast f.e.):

  1. Audio: a textalternative is provided that presents equivalent information.
  2. Video: either a text alternative or an audio track is provided that presents equivalent information.
    >> This is relevant for all our podcast f.e. The upload function for Audio and Video must have a text alternative descritpion field!
  3. Captions to the Video is provided. Captions not only include dialog, but identify who is speaking.

Adaptable

  1. Info and Relationships: Information, structure, and relationships conveyed through presentation can be programmatically determined or are available in text.
  2. Meaningful Sequence:When the sequence in which content is presented affects its meaning, a correct reading sequence can be programmatically determined.
  3. Sensory Characteristics: Instructions provided for understanding and operating content do not rely solely on sensory characteristics of components such as shape, size, visual location, orientation, or sound.
Timing Adjustable:

For each time limit that is set by the content, at least one of the following is true:

  1. Turn off: The user is allowed to turn off the time limit before encountering it; or
  2. 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
  3. 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
  4. 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
  5. Essential Exception: The time limit is essential and extending it would invalidate the activity; or
  6. 20 Hour Exception: The time limit is longer than 20 hours.

Note: This success criterion acts to ensure that changes in content or context as a result of a time limit will not occur unexpectedly, which could prevent users from completing tasks. While exceptions to Success Criterion 2.2.1 where timing is essential exist, guideline 2.2 in general limits changes in content to those places where there is no other option. This success criterion should be considered in conjunction with Success Criterion 3.2.1 which puts limits on changes of content or context as a result of user action.

Pause, Stop, Hide:

For moving, blinking, scrolling, or auto-updating information, all of the following are true:

  1. Moving, blinking, scrolling: For any moving, blinking or scrolling information that (1) starts automatically, (2) lasts more than five seconds, and (3) is presented in parallel with other content, there is a mechanism for the user to pause, stop, or hide it unless the movement, blinking, or scrolling is part of an activity where it is essential; and

  2. Auto-updating: For any auto-updating information that (1) starts automatically, (2) lasts more than five seconds, and (3) is presented in parallel with other content, there is a mechanism for the user to pause, stop, or hide it or to control the frequency of the update unless the auto-updating is part of an activity where it is essential.

    Note 1: For requirements related to flickering or flashing content, refer to Seizures.

    Note 2: Since any content that does not meet this success criterion can interfere with a user's ability to use the whole page, all content on the Web page (whether it is used to meet other success criteria or not) must meet this success criterion.

    Note 3: Content that is updated from a process, real-time or remote stream is not required to preserve or present information that is generated or received between the initiation of the pause and resuming presentation, as this may not be technically possible, and in many situations could be misleading to do so.

    Note 4: An animation that occurs as part of a preload phase or similar situation can be considered essential if interaction cannot occur during that phase for all users, and if not indicating progress could confuse users or cause them to think that content was frozen or broken.

Seizures
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.

Note: Since any content that does not meet this success criterion can interfere with a user's ability to use the whole page, all content on the Web page (whether it is used to meet other success criteria or not) must meet this success criterion.

Navigable
  1. Bypass Block
    A mechanism is available to bypass blocks of content that are repeated on multiple Web pages. Understanding Success Criterion
  2. Page Titeled
    Web pages have titles that describe topic or purpose.
  3. Focus Order:If a Web page can be navigated sequentially and the navigation sequences affect meaning or operation, focusable components receive focus in an order that preserves meaning and operability. Understanding Success Criterion >>f.e. on home the language select should be first. That we detect the language setting on loading the page could be useful so the site apears in the probably right language right away. How can we open the drop down?
  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.
Predictable

  1. On Focus:When any component receives focus, it does not initiate a change of context. Understanding Success Criterion

  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. Understanding Success Criterion

Input Assistance

  1. 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.
  2. Labels or instructions are provided when content requires user input.

Compatible

  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. Understanding Success Criterion

  2. Name, Role, Value: For all user user interface components (including but not limited to: form elements, links and components generated by scripts), the name and role can be programmatically determined; states, properties, and values that can be set by the user can be programmatically set; and notification of changes to these items is available to user agents, including assistive technologies. Understanding Success Criterion

Note: This two success criterion is primarily for Web authors who develop or script their own user interface components. For example, standard HTML controls already meet this success criterion when used according to specification.

 

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