You should take care that your website is not "unreasonably difficult" for a disabled person to use. That is not only a good thing in itself, but a legal requirement under the Disability Discrimination Act (DDA). The law doesn't make clear exactly what standards have to be met, and it's not been tested in court yet, but there are various guidelines for Web Accessibility with which you should comply.
They cover things like...
- Making sure that all images have alternate text descriptions for screen reader programs (as used by the visually impaired) to detect.
- Ensuring high colour contrast between text and background
- Ensuring your pages have a technically correct markup structure so that when all display styles are removed, the 'hierarchy' of the page - its heading, subheadings and body text - is clear
A good, quick, simple test (if you are using a suitable browser with suitable facilities) is to select a page, turn display of images off, and turn off all 'stylesheets' (that is, view the page with no page styles applied). The resulting page will look very dull, but it should be properly laid out, the missing images should be explained appropriately and the structure of the page content should be clear. If it isn't, you have a problem. (Note that if you have used one of those drop-down, fly-out etc. menu systems, you may find the results of this little test rather interesting...)
The Web Accessibility Initiative (WAI) has produced guidelines for various levels of compliance which are generally accepted and recognised. (The British Standards Institute's own guide - PAS 78 - refers extensively to WAI.) There are various free tools which can test your pages against the WAI guidelines. If you use them, interpret the results carefully - at first glance the results can sometimes look scary even for a 'good' page.
If you think you have a problem with accessibility, you may have reached the point where you need to talk to an expert. Choosing the right Technology can prevent most accessibility problems from arising in the first place.
Last updated: July 2008