Using automated tools are a tremendous help in figuring out problematic code or color contrasts that just don’t feel like they are sufficient. However, your testing shouldn’t end there!
Similarly, don’t assume that a non-disabled person testing their site or application with assistive technologies is good enough. I’ve been asked by well-intentioned fellow non-disabled web designers, “Well, how can we get our hands on a screen reader to do testing?”
The best way to ensure your experience is as accessible as possible is to reach out to actual disabled users for testing.
This hit home for me when I watched Scott Mayer (Multiple Facets of Accessible Design – Scott Mayer presentation) demonstrate how blind users navigate both good and bad experiences via a screen reader.
For one, the speed at which the automated voice spoke was surprisingly rapid — and he even slowed it down for our benefit! Two, a sighted user trying their hand at a screen reader just isn’t the same as someone who is completely dependent on one and uses it day in and out.
Sure, a web surfer with hearing can plug their ears and watch a video, but afterwards, they can simply unplug them and go about their lives. A deaf user doesn’t have that luxury. You may think a pretend session gives you a glimpse into their world, but it doesn’t really.
Having access to disabled testers may be challenging depending on the resources in your area. There are some alternatives on the web, such as forums like the Accessify Forum, where you can post a site and ask for feedback.
The bottom line is that, whenever possible, you should use multiple avenues of testing for accessibility, the best being actual disabled users who could be part of your audience.