By: Nicky Danino

May 17th, 2002

Reader Rating: 8.5

If the World Wide Web is to ever become a truly universal medium, then changes have to be made to make it accessible to everyone. Nowadays, most television programmes have subtitles for deaf viewers, buildings are made accessible to wheelchair users, and books are recorded so that people can listen to them. Now it's time to apply these same principles to the Web!

Accessibility - Who Cares?

Accessibility simply means providing flexibility to accommodate each user's needs and preferences. In an Internet context, accessibility is making computer technology and Internet resources useful to more people than would otherwise be the case. We need Internet accessibility because it expands a Website's potential audience to the millions who are required to use alternative browsing technologies.

But even for people who do not have any specific physical or mental characteristics that affect computer use, it has been found that the adoption of universal design principles can:

• reduce fatigue,
• increase speed,
• decrease errors, and
• decrease learning time for all users.

In many ways, universal design addresses the larger issues of usability and makes things easier for everyone.

Get with the Guidelines

On May 5, 2000, the World Wide Web Consortium's (W3C) Web Accessibility Initiative published the Web Content Accessibility Guidelines 1.0, known as WCAG for short. The WCAG have been implemented on many sites and can be used very effectively to develop an accessible Website.

The Content Accessibility Guidelines designated as high priority items are:

1. provide equivalent alternatives to auditory and visual content


2. don't rely on colour alone


3. use mark-up and style sheets properly


4. clarify natural language use


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

Do-It-Yourself Accessibility

So how can you ensure that your Website is actually accessible? You have read the guidelines, made sure that you followed them as closely as possible, but how can you check them? Luckily, there are quite a few things that you can do.

Firstly, you can check the site yourself:

1. Turn off graphics


2. Turn off sounds


3. Check the contrast by viewing the page in greyscale


4. Turn off style sheets


5. Turn off scripts, applets, or other programmatic objects


6. Use the largest font size allowed by a browser


7. Resize the browser window


8. Select all text and copy it into a word processor to make sure it makes sense

Once you're satisfied that you've made your Website as usable as possible under these conditions, why not try using an automated accessibility tool? There's a number of free, easy-to-use tools out there that can help make sure your site complies with accessibility guidelines.

1. Bobby

www.cast.org/bobby [1]

The Web Content Accessibility Guidelines explain how to make multimedia content, such as images and video, more accessible to a wider audience, and Bobby checks for the accessibility issues described in these guidelines.

Bobby can provide automatic checks for only a limited number of accessibility problems. For instance, it's is useful for locating missing text alternatives to visuals and for checking for untidy HTML coding. But more is needed to ensure that a site is accessible to all users.

For example, Bobby can't evaluate a site for layout consistency, ease of navigation, provision of contextual and orientation information, or the use of clear and easy to understand language. Nor can the program check what a site will look like without graphics or colours, under different resolutions, or using different font sizes or through a text-only browser.

As such, Bobby produces a very large report, much of which consists of recommendations that the site's author conduct manual checks (which may actually turn out to be unnecessary).

2. A-Prompt

http://aprompt.snow.utoronto.ca/ [2]

A-Prompt is a stand-alone tool developed at the University of Toronto. Developers install the program on their own computer, and specify which file they would like to evaluate. The program then takes the user through a wizard-style succession of questions and answers, at the completion of which the file is updated to incorporate any changes the developer has made upon recommendation by the software.

Although A-Prompt makes recommendations based on sound principles, the actual changes to the file are made by the developer, so this person still needs to have a solid understanding of the underlying principles of accessibility.

3. Lift Online

http://www.usablenet.com/ [3]

LIFT (UsableNet, 2000) is a core semantic analysis technology that's packaged in several forms by UsableNet to meet various developer and tester needs.

It was first released in April, 2000 as a usability analyser, but naturally progressed to include accessibility over the past year. Basically LIFT is a software Web analysis engine that can be applied in several ways.

A Web-based trial is available (at the UsableNet home page), which will evaluate five pages starting at a specified URL (you can repeat that process with as many URLs as you want).

LIFT is also available for purchase as a Macromedia Dreamweaver product, which adds to Dreamweaver menus options that allow the developer to test for accessibility.

4. 508/W3C Accessibility Suite for Macromedia Dreamweaver and Dreamweaver UltraDev

This free extension was developed by UsableNet and offers developers the ability to check individual pages or even an entire site against a customizable set of accessibility guidelines.

The 508 Accessibility Suite offers a comprehensive set of tests similar to LIFT Online. Perhaps most important, it takes advantage of the authoring environment of Dreamweaver to point the Web content designer/developer to specific places on the page in need of revision.

5. The Wave

http://www.temple.edu/inst_disabilities/piat/wave/ [4]

The Wave is a tool that helps people perform those tasks that require human judgment (e.g. "Does this ALT text a functional equivalent for this image?" "Does this reading order make sense?").

The Wave:

• displays the ALT text of images, and higlights areas on the page for comparison with the images
• provides numbered arrows to show the linearized reading order
• shows the HTML equivalent (if any) provided for applets
• performs automatic checks (detects missing or suspicious ALT text)

However, at this time its fcuntionality far from covers all accessibility checkpoints.

6. HTML and CSS Validators

http://validator.w3.org/ [5]

http://jigsaw.w3.org/css-validator/ [6]

The HTML Validator and CSS Validator from the W3C are particularly helpful for advanced users. These free tools don't check for accessibility issues; rather, they check for the proper use of HTML and CSS.

This is mostly helpful for designers and developers who know HTML and CSS but not the relevant techniques that help improve accessibility. The HTML and CSS validators can spot incorrect coding and indicate possible solutions.

Accessibility Made Easy

Accessibility is no longer a nice-to-have -- it's essential to the Web's evolution. Validation should include a combination of automated and manual checks.

The automated tools look for apparent problems with the accessibility of a page, while the manual checking methods generally address the continuity and flow of content. But in all cases, the goal is to make information accessible to as many users in the target audience as possible. Don't let the rules get in the way of allowing all visitors to get the information they need, and sparing them the information they do not.

[1] http://www.cast.org/bobby
[2] http://aprompt.snow.utoronto.ca/
[3] http://www.usablenet.com/
[4] http://www.temple.edu/inst_disabilities/piat/wave/
[5] http://validator.w3.org/
[6] http://jigsaw.w3.org/css-validator/