Principles of Accessibility: Principle 2 - Operable
Defining WCAG 2.0 Level AA Guidelines
Principle 2 - Operable
Guideline 2.1 - Keyboard Accessible
Make all functionality available from a keyboard.
- 2.1.1 - Keyboard [A]
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. Understanding 2.1.1
- 2.1.2 - No Keyboard Trap [A]
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 or other standard exit methods, the user is advised of the method for moving focus away. Understanding 2.1.2
Guideline 2.2 - Enough Time
Provide users enough time to read and use content.
- 2.2.1 - Timing Adjustable [A]
For each time limit that is set by the content, at least one of the following is true:
- Turn off: The user is allowed to turn off the time limit before encountering it.
- 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.
- 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.
- 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.
- Essential Exception: The time limit is essential and extending it would invalidate the activity.
- 20 Hour Exception: The time limit is longer than 20 hours.
- 2.2.2 - Pause, Stop, Hide [A]
For moving, blinking, scrolling, or auto-updating information, all of the following are true:
- 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
- Auto-updating: For any auto-updating information that (1) starts automatically and (2) 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. Understanding 2.2.2
Guideline 2.3 - Seizures [A]
Do not design content in a way that is known to cause seizures.
- 2.3.1 - Three Flashes or Below Threshold [A]
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. Understanding 2.3.1
Guideline 2.4 - Navagable
Provide ways to help users navigate, find content, and determine where they are.
- 2.4.1 - Bypass Blocks [A]
A mechanism is available to bypass blocks of content that are repeated on multiple Web pages. Understanding 2.4.1
- 2.4.2 - Page Titled [A]
Web pages have titles that describe topic or purpose. Understanding 2.4.2
- 2.4.3 - Focus Order [A]
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 2.4.3
- 2.4.4 - Link Purpose [A]
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. Understanding 2.4.4
- 2.4.5 - Multiple Ways [AA]
More than one way is available to locate a Web page within a set of Web pages except where the Web Page is the result of, or a step in, a process. Understanding 2.4.5
- 2.4.6 - Heading and Labels [AA]
Headings and labels describe topic or purpose.Understanding 2.4.6
- 2.4.7 - Focus Visible [AA]
Any keyboard operable user interface has a mode of operation where the keyboard focus indicator is visible.Understanding 2.4.7