Technique F41:Failure of Success Criterion 2.2.1, 2.2.4, and 3.2.5 due to using meta refresh to reload the page
Applicability
HTML and XHTML
This technique relates to:
- 2.2.1: Timing Adjustable (Failure)
- 2.2.4: Interruptions (Failure)
- 3.2.5: Change on Request (Failure)
Description
meta http-equiv of refresh is often used to periodically refresh pages or to redirect users to another page. If the time interval is too short, and there is no way to turn auto-refresh off, people who are blind will not have enough time to make their screen readers read the page before the page refreshes unexpectedly and causes the screen reader to begin reading at the top. Sighted users may also be disoriented by the unexpected refresh.
Examples
Example 1
This is a deprecated example that changes the user's page at regular intervals. Content developers should not use this technique to simulate "push" technology. Developers cannot predict how much time a user will require to read a page; premature refresh can disorient users. Content developers should avoid periodic refresh and allow users to choose when they want the latest information. (The number in the content attribute is the refresh interval in seconds.)
<html xmlns="http://www.w3.org/1999/xhtml" lang="en"> <head> <title>HTML Techniques for WCAG 2.0</title> <meta http-equiv="refresh" content="60" /> </head> <body> ... </body> </html>
Tests
Procedure
For a page that uses meta http-equiv="refresh"
:
- Check that the numerical value for seconds until refresh in the
content attribute is present. - Check that the numerical value for seconds until refresh in the
content attribute is less than one or greater than 72,000. - Check if the page qualifies for Real-time or Essential Exceptions in Success Criterion 2.2.1 Timing Adjustable.
- Check if the user is provided an opportunity to turn off, extend, or adjust the timing of the page refresh.
- Check if the page does not refresh after the duration specified in the
content attribute.
Expected Results
- If checks #1-5 are false then this failure condition applies and content fails Success Criteria 2.2.1.
- If checks #1, #2, #4, and #5 are false, this failure condition applies and the content fails Success Criterion 2.2.4.
- If checks #1 and #4 are false then this failure condition applies and content fails Success Criterion 3.2.5.