building for accessibility

Compatibility, as you've read, is a major theme of web production. In order to reach the widest possible audience, you have to build a site that will display appropriately on computers with different platforms, browsers, and connection speeds.

But along with technical disparities, it's important to consider the different physical needs of users. There are millions of sight- and hearing-impaired people online, who customize their browsers to compensate for their disabilities. With just a small amount of thought and effort, you can make your site accessible to them.

it's not just nice it's smart

In the real world, modifications made for the disabled usually help everyone. The ramps cut into curbs, for instance, make city sidewalks navigable for people in wheelchairs. But they also help bicyclists, rollerbladers, scooter-riders, suitcase-draggers, and pram-pushers get around with ease.

Similarly, the modifications you make to your site to help people who are blind or deaf will serve your entire audience and your bottom line. Most of the needed modifications involve improving annotations (such as offering short text descriptions of images) or structuring your site in a more logical manner, so it can be analyzed by a browser for the blind.

But these changes not only help disabled users, they also help ensure a clear, logical experience for everyone. In the process, they also make your site more accessible to search engines (important for building traffic) and more compatible with future applications, beyond the browser.

and in america, it's the law

If your site is for a U.S. government agency or an organization that receives government funds or contracts you're actually required by law to make it accessible to those with disabilities. In 1998, the Rehabilitation Act was amended, requiring federal agencies to make their information technology (including web sites) accessible to people with disabilities.

The implications are explained here: http://www.section508.gov.

accommodating disabled visitors

In order to make your site accessible, there are two main user groups to consider:

  • Sight-impaired users who navigate the web using a screen-reader (which reads the page aloud) or a braille browser (which prints out each page in braille).

  • Hearing-impaired users who make use of close-captioning technologies to translate audio material into text captions.

sight-impaired users The web poses obvious challenges for people who are sight-impaired. It's almost exclusively a visual medium, providing few tactile or audio clues to aid understanding. However, internet tools for the blind are quite sophisticated. By reading a page aloud or printing it out in braille they allow people to use the web without the benefit of sight. Unfortunately, there remain a few barriers to effective use.

Making your site accessible?

'Bobby' (checks your accessibility)

http://bobby.watchfire.com/

Web Accessibility Initiative

http://www.w3.org/wai

IBM Web Accessibility checklist

http://www.ibm.com/able/accessweb.html


3 challenges for the sight-impaired:

  1. Interpreting images. Images are often used to replace words on web sites. And if the site doesn't provide text equivalents for these images especially the ones used in navigation it can't be understood by a blind person. "The first rule for accessibility is providing a text equivalent for everything that's visual," says Matt Margolin, who's writing a book on the subject. "It's simple, but it takes time."

  2. Understanding page structure. Many sight-impaired users navigate pages with a screen reader, which calls out the headlines and subheads that divide a page. However, not all sites use headline tags to structure their pages; some rely on purely visual cues (like the font tag or images) and ignore document structure. These unstructured pages are difficult to interpret both by screen readers and other applications.

  3. Reading small text. Designers are often tempted to use a small font, because it saves space on the screen. But many people (not just the blind) struggle to read the tiny text on these sites. This can be addressed by using larger type or giving users different size options.

hearing-impaired users The web is still primarily a text-based medium, but as bandwidth and audio-compression have improved, some sites have moved toward a richer multimedia experience. If your site incorporates audio information, you should of course consider the needs of hearing-impaired users.

This is especially important in the arena of online learning, where audio and video often figure prominently into the educational experience.

2 challenges for the hearing impaired:

  1. Understanding what's being spoken in audio soundtracks or videos. They can't rely on reading lips, because the person speaking isn't always pictured, and poor video quality distorts mouth movements. This problem can be addressed by subtitles.

  2. Understanding non-verbal clues, such as a siren or the sound of a door slamming, in audio soundtracks or videos. These can be explained with captions (e.g. "A door slams in the background.")

5 easy fixes to make your site more accessible

  1. Offer a text description of each image. Every image on your site should have a brief text description of what's pictured (This is known as "alt" text.) Lots of images? Focus first on those used in navigation.

  2. Offer text-based navigation. What's true for regular images is especially true for navigation: Make sure you have a functional text equivalent for every navigational clue, including nav bars, image maps, icons, and buttons.

  3. Use stylesheets, not font tags. Both font tags and stylesheets can be used to change the appearance of words on a web page. But stylesheets also allow you to indicate what kind of text it is: Headline? Sub-head? Body text? And this context helps blind users navigate the page.

  4. Let users change the font size. To help people (especially seniors) read your site, offer the web-equivalent of a large-print edition. This is easier than ever, with stylesheets.

    graphics/183fig01.gif

    graphics/183fig02.gif

    Above: Wired News readers can choose between different sized text. Left: Tupperware.com offers a large-print version.

  5. Provide subtitles for audio. This is labor-intensive, but a do-it yourself captioning tool, called MAGpie, can help. It's offered for free by the National Center for Accessible Media: http://ncam.wgbh.org.


To evaluate how accessible your site is, try the free service, "Bobby" (http://bobby.watchfire.com). Margolin also recommends viewing your site with a text browser, like Lynx. "If your pages can be rendered in text, chances are really, really good they can be rendered using a braille browser or a screen reader."



The Unusually Useful Web Book
The Unusually Useful Web Book
ISBN: 0735712069
EAN: 2147483647
Year: 2006
Pages: 195
Authors: June Cohen

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