Accessibility

Think of your users.

Unit Goals

To have a working knowledge of accessibility issues and to know where to go for more information.

A Definition

Accessibility commonly refers to the activity of making applications highly usable for people with disabilities.

We’re interested here in web accessibility, which focuses on accessibility in web applications.

References

The most important and comprehensive site discussing Web Accessibility is the W3C's Web Accessibility Initiative (WAI). Their home page has a list of Resources, including introductions, tips, FAQs, guidelines, checklists and descriptions of techniques for making sites accessible.

The WAI

Of particular interest to Web Designers is the W3C's Web Content Accessibility Guidelines. This should be considered required reading. It describes 14 guidelines for making web content accessible:

  1. Provide equivalent alternatives to auditory and visual content.
  2. Don't rely on color alone.
  3. Use markup and style sheets and do so properly.
  4. Clarify natural language usage
  5. Create tables that transform gracefully.
  6. Ensure that pages featuring new technologies transform gracefully.
  7. Ensure user control of time-sensitive content changes.
  8. Ensure direct accessibility of embedded user interfaces.
  9. Design for device-independence
  10. Use interim solutions.
  11. Use W3C technologies and guidelines.
  12. Provide context and orientation information.
  13. Provide clear navigation mechanisms.
  14. Ensure that documents are clear and simple.

Under each guideline are several checkpoints. There are over 60 checkpoints in all. The W3C has published a prioritized list of these checkpoints. They are ranked as follows:

Priority 1 ("Must") Rules
If these aren't satisfied some users will not be able to access some information.
Priority 2 ("Should") Rules
If these aren't satisfied some users have difficulty accessing some information.
Priority 3 ("May") Rules
If these aren't satisfied some users will have a little difficulty access some information.

The W3C's checklist is excellent: you would be wise to read all these checkpoints (there are a few dozen!) and look at the associated implementation techniques that accompany them. (This could take upwards of 20 hours to read and study properly, even for experienced web designers, but is well worth it.)

ARIA

ARIA stands for Accessible Rich Internet Applications. Check out:

Exercise: Add some ARIA to an existing webapp of yours.

Who Has an Accessible Site?

You can certify yourself that you conform to W3C Accessibility Checkpoints and put a logo on your conforming pages. You can claim Level A (Priority 1 checkpoints met), Double-A (Priority 1 and 2 met) or Triple-A (Priority 1, 2, and 3 checkpoints met). If you use these logos you are responsible for actually meeting the checkpoints.

The ca.gov site has an entire section of their site detailing their conformance to accessibility requirements.

Neilsen on Accessibility

The Nielsen Norman Group has lots of articles on accessibility. These are required reading!

Exercise: Search the NN/g articles for more on accessibility. Note NN/g has been publishing online articles for decades!

More Resources

Here are some notes on teaching accessibility.

Like React? Here is the Accessibility Guide from the official React docs.

Summary

We’ve covered:

  • A definition of accessibility
  • The WAI
  • ARIA
  • Where to find more information