Delayed refresh under 20 hours must not be used
How to Fix the Problem
Either remove the http-equiv="refresh"
attribute from each
meta
element in which it is present or increase the refresh time
to be greater than 20 hours.
To modify this example and make it accessible, remove the
http-equiv="refresh"
attribute from the
meta
element.
Bad Example
<meta http-equiv="refresh" content="10" url="http://www.yourdomain.com/index.html">
If the purpose of the <meta>
element is to refresh the
page, this should be handled through JavaScript. Furthermore, additional
scripting should be used to provide users the ability to pause the refresh,
extend the time between refreshes, or to turn the refresh off entirely.
For more information, see Timed Content in the Dynamic Content section of the HTML and CSS Accessibility course.
Why it Matters
Since users do not expect a page to refresh automatically, such refreshing can be disorienting. Refreshing also moves the programmatic focus back to the top of the page, away from where the user had it. Such resetting is frustrating for users.
Redirection and page refresh through the use of the
<meta>
element is problematic for users with disabilities
in many ways. The primary reason why redirects and refreshes are problematic
is that the user has no control over when the redirect or refresh occurs. If
the purpose of the <meta>
element is to redirect the user
to a new location, server-side means should be employed instead of
client-side. Content that moves or auto-updates can be a barrier to anyone who
has trouble reading the stationary text as quickly as well as to anyone who
has trouble tracking moving objects. It can also cause problems for screen
readers.
Rule Description
The document must not use <meta http-equiv="refresh">
with
a refresh time of less than 20 hours because it can prevent control over when
the refresh occurs for users with disabilities.
The Algorithm (in simple terms)
Checks for the presence of the http-equiv="refresh"
attribute on
the meta
elements with a content
value less than 20
hours.