Let users extend time limits tenfold
G180 gives the reader a way to change a time limit at the beginning of their session, before any activity the clock applies to. W3C prefers a variable adjustment letting people set any value in the range. Fixed increments are the weaker alternative. This is a sufficient technique for 2.2.1 Timing Adjustable at Level A. W3C's test is the interesting part, because it proves the setting rather than finding it. Set the limit to ten times the default, start a timed action, then wait past the original limit and check that nothing expires until the new one runs out. That ten-times figure is not arbitrary. It runs through this whole family of timing techniques as W3C's working estimate of how much longer a task can take.
How we find it in an audit
Our reviewers find the setting first, then prove it. We set the longest option available, start the timed task, and wait out the original limit with a stopwatch running. A control that stores a preference the timeout code never reads is a common and entirely invisible failure, and the only way to catch it is to sit through the wait.
How affected users experience it
Time limits are set from an average, and everybody who is not average pays for it. Reading a page through speech takes longer. So does typing with a switch, tracking a form under magnification, or working out what a question means when processing takes effort. Being allowed to set the limit yourself, before you start, is the difference between a form you can finish and a form that throws your work away.
Passes vs. fails
Passes
Page one asks how much time you want per page, offering 20 minutes as the default, 60 minutes, or 200, and the choice applies to the whole application.
Fails
A visa application silently expires after 20 minutes per page, so slow typists lose everything on submission with no way to change the limit.
How this gets tested
The W3C publishes test rules that define what a checker looks for here.
- Meta element has no refresh delayA tool can check this
- Meta element has no refresh delay (no exception)A tool can check this
Other ways to satisfy this rule
11 guides on this site are filed under 2.2.1 Timing Adjustable. W3C lists this one as sufficient for that rule on its own. Implement it correctly, in a way your readers' software actually supports, and the rule is met.
- G4sufficientLet users pause moving content and resume it
- G133sufficientOffer longer session limits before forms begin
- G198sufficientLet users switch time limits off entirely
- SCR1sufficientLet users extend a script's time limit
- SCR16sufficientWarn users before a time limit runs out
- SCR33sufficientGive scrolling content a pause and a resume
This guide is our interpretation of W3C technique G180: Providing the user with a means to set the time limit to 10 times the default time limit. W3C publishes its techniques as guidance rather than as the standard, and says so on every one of them. The success criterion is what conformance is measured against, and a technique is one documented way to meet it.