Extended time typically refers to allowing a test-taker or employee extra time to complete a test or training. Because the ADA does not require employers to lower production standards, extended time does not usually mean allowing an employee more time to perform a job function.
The amount of extended time should be correlated to the disability or limitations. Common examples of extended time for test-taking include: time and a half, double time, and unlimited time. For learning a new job or task, the amount of extended time is usually whatever time is needed, up to the point the extension creates an undue hardship.
For more information regarding testing accommodation, see JAN's A to Z by Topic: Testing Accommodations