Thursday, September 29, 2005

Accessibility Compliance

What is Accessibility Compliance?

As was mentioned in the previous discussion on code compliance, there is some substantial overlap between code and accessibility compliance. However, the one distinction is that code compliance is more geared toward coding a webpage in a way that it will be functional for all methods of viewing it, and accessibility deals more with ensuring that it is easily comprehensible by all people viewing it.

The common association with accessibilty standards is that these are for viewers with disabilities. That is not wholly accurate, but it is part of what they are for. Overall, you want to create your site in a way that you do not alienate your visitors due to either technical or physical limitations. For technical limitation, think of how your website would be viewed by someone using an alternative method of accessing the Internet (such as a small cell phone or PDA display, or even an in-vehicle dash display). For physical limitations, you should keep in mind that millions of people accessing the Internet are disabled in some way. An easy comparison is that your business would not be considered respectable if you didn't allow for handicap access ramps, or other accomodations for those with limitations, so why would you consider doing that with your online business presentation.

These standards are, most certainly, considered something that is not only proper etiquette for a website to use, but also extremely good for business. However, U.S. government websites are now required to make their websites accessible, and anyone who plans to work as a web developer in any sector or sub-sector of the U.S. government should make certain they understand how to make a site accessible.

The Web Accessibility Initiative (WAI) which is a large subgroup of the W3C. When you are dealing with creating a webpage(site) that follows the standards set by the WAI, you will be following the Web Content Accessbility Guidelines (WCAG). The current standards set for WCAG is version 1.0 and contains 14 general principles of accessible web design. Keep in mind that these are just categories, and there are many elements within each.

14 General Principles of for WCAG 1.0
  1. Provide equivalent alternatives to auditory and visual content. (ex: using alternative text for images that don't display)
  2. Don't rely on color alone. (making sure that there is proper color use, and that the site is still understandable if it was all black & white)
  3. Use markup and style sheets and do so properly. (this goes along with code compliance & separating design from code)
  4. Clarify natural language usage. (indicating the site language in code, and explaining any abbreviations)
  5. Create tables that transform gracefully. (use tables for tabular data mostly, and make sure to lable your tables using headers and footers to describe what they are)
  6. Ensure that pages featuring new technologies transform gracefully. (make sure that your page still is understandable without all the frills - like scripts and flash)
  7. Ensure user control of time-sensitive content changes. (anything that is active on your page - like scrolling or blinking or sound - should be able to be turned off by the user)
  8. Ensure direct accessibility of embedded user interfaces. (again, making sure your site layout follows guidelines)
  9. Design for device-independence. (take into account that users may be using various methods to access your site, and provide alternate ways to get to information - like shortcuts and links)
  10. Use interim solutions. (Don't wait, start changing your site now.)
  11. Use W3C technologies and guidelines. (Be sure to use the current coding standards.)
  12. Provide context and orientation information. (ex: Clearly lable your page and data sections - especially if you use frames.)
  13. Provide clear navigation mechanisms. (ex: Use a consistent navigation layout for your whole site - not putting the links on the left on one page, then the right on the next.)
  14. Ensure that documents are clear and simple. (Keep your information relavant, and use language that is understandable by your readers.)
Now, as I said above, there are subaspects to each, and those will be addressed in a later article. However, if you want to jump ahead you can take a look at the full page explanation of the WCAG 1.0 list of 14 needed aspects.

The 3 Priority Levels & Conformance
Each of the 14 guidelines has checkpoints within it. For instance, let me give you an example of one of the checkpoints for the first guideline.
Guideline 1. Provide equivalent alternatives to auditory and visual content.
Checkpoint 1.1. Provide a text equivalent for every non-text element (e.g., via "alt", "longdesc", or in element content). This includes: images, graphical representations of text (including symbols), image map regions, animations (e.g., animated GIFs), applets and programmatic objects, ascii art, frames, scripts, images used as list bullets, spacers, graphical buttons, sounds (played with or without user interaction), stand-alone audio files, audio tracks of video, and video.
Priority Level: 1

Each checkpoint is assigned a specific priority. There are 3 levels of priorities possible for each checkpoint.
  • Priority 1 : A Web content developer must satisfy this checkpoint. Otherwise, one or more groups will find it impossible to access information in the document. Satisfying this checkpoint is a basic requirement for some groups to be able to use Web documents.
  • Priority 2: A Web content developer should satisfy this checkpoint. Otherwise, one or more groups will find it difficult to access information in the document. Satisfying this checkpoint will remove significant barriers to accessing Web documents.
  • Priority 3: A Web content developer may address this checkpoint. Otherwise, one or more groups will find it somewhat difficult to access information in the document. Satisfying this checkpoint will improve access to Web documents.
Now, based on whether or not you followed each of the checkpoints for the 14 guidelines, and which priorities you completed, your website may lay claim to a certain level of conformance. If you've seen websites with a little button that says 'AA' or 'AAA' then you will understand where that comes from in the following list.
  • Conformance Level "A": All Priority 1 checkpoints are satisfied.
  • Conformance Level "AA": All Priority 1 and 2 checkpoints are satisfied.
  • Conformance Level "AAA": all Priority 1, 2, and 3 checkpoints are satisfied.
So, overall, you want to aim for following the conformance to the highest level that you can. Aiming for 'A' is a minimum. You want to always aim for the 'Triple-A' ranking.

~Nicole

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