Timed Events
In general, time limits should not be imposed on activities unless the activity by its nature requires a time limit.
Some users with disabilities may need more time to complete an activity that has a time limit on it.
- People with physical disabilities often need more time to react, to type and to complete activities.
- People with low vision need more time to locate things on screen and to read.
- People who are blind and using screen readers may need more time to understand screen layouts, to find information and to operate controls.
- People who have cognitive or language limitations need more time to read and to understand.
- People who are deaf and communicate in sign language may need more time to read information printed in text (which may be a second language for some).
- In circumstances where a sign-language interpreter may be relating audio content to a user who is deaf, control over time limits is also important.
- People with reading disabilities, cognitive limitations, and learning disabilities who may need more time to read or comprehend information can have additional time to read the information by pausing the content.
Accessible Time Limit Implementations
There are options for handling time limits in accessible ways. You can allow the user to
- turn off the time limit
- adjust the time limit to a length at least 10 times the original length
- extend the time limit at least 10 times, and allow the user at least 20 seconds each time to respond to the prompt through a simple action, like pressing the space bar, to extend the time
Exceptions to the Time Limit Requirement
There are also exceptions to the time limit rule. A time limit is allowed if it is
- a required part of a real-time event and no alternative is possible (like an auction)
- essential and extending the time limit would invalidate the activity
- longer than 20 hours
What is an example of removing a time limit that invalidates the activity?
An on-line ticket-purchasing site gives the user two minutes to confirm a purchase before the seats are returned to the general pool. Because tickets on such sites can sell out quickly, holding a ticket longer than that may invalidate the nature of the site, so this is a case in which the timing is essential and cannot be extended without invalidating the activity. However, the site does move as much of the process out of the time-critical period as possible, for instance allowing users to provide necessary information like name, payment method, etc., before entering the time-critical stage.
Further Reading
- Understanding Timing Adjustable Requirements (WCAG) from which much of this document was based on