NVDA – a free, open source screen reader
Testing your work with a screen reader, especially if you’re building something that is more advanced than a basic info website, is likely to help you create a more accessible website.
The best thing is to have actual screen reader users test your work, but that isn’t always feasible to do on a day-to-day basis unless you happen to have a co-worker who uses a screen reader. So being able to do some testing on your own is pretty much a necessity.
There are several screen readers to choose from, but one that is particularly appealing is NVDA. It is free, open source, works with Firefox, and has support for WAI-ARIA. The catch is that NVDA is Windows only, so Mac users like myself will need to use virtual machine software like Parallels Desktop or VMWare Fusion to run it. I can live with that.
If you’re wondering why testing with Apple’s VoiceOver screen reader (which is shipped with Mac OS X) is not enough, there are a few reasons. One is that VoiceOver doesn’t have that great support for WAI-ARIA yet, another that it lacks some features that NVDA has, and a third that, just like testing with several different web browsers, it’s good to test with several different screen readers.
To start using NVDA, download the latest development snapshot and then read the NVDA User Guide.