Making The Web Accessible

Leading the Web to its full potential.
Good design is accessible design
Charles McCathieNevile -- charles@w3.org
This talk will be available online from next week:
http://www.w3.org/Talks
Overview
- Why accessibility?
- W3C and WAI
- Principles of accessible design
- Quick Tips, Guidelines and more
- Fix this! - a sample site
- Resources to get started
- Questions.
I. Why Accessibility?
- People
- Design
- Market
- Law
People: Doors opened by the Web
- Web is fastest-adopted technology in history
- Displacing traditional sources of information and interaction
- Web is becoming a key resource for:
- news, information, commerce
- classroom education, distance learning
- job searching, workplace interaction
- civic participation
People: Access for all
People: Barriers to Access
Many users may be operating in contexts very different from your own:
- They may not be able to see, hear, move, or may not be able to process
some types of information easily or at all.
- They may have difficulty reading or comprehending text.
- They may not have or be able to use a keyboard or mouse.
- They may not speak or understand fluently the language in which content
is written or spoken.
Design: Functional Requirements
Similar functional requirements for able-bodied users in other
environments:
- Eyes-busy/Hands-busy environment: voice output
- Noisy/Silent environment: captioning.
- Low bandwidth: alternatives to images, video, etc.
- Voice browsing: voice input/output
- They may have a text-only screen, a small screen, or a slow Internet
connection.
- They may be in a situation where their eyes, ears, or hands are busy or
interfered with (e.g., driving to work, working in a loud environment,
etc.).
- Mobile access: limited screen area, screen magnifier
Design: Device Independence
- Device-independent design is accessible/universal design.
- Separate structure from presentation and reach mobile devices, Web-TV,
kiosks, search engines, etc.
- Different learning styles; low literacy levels; second-language
access
- Easier site maintenance (e.g., style sheets shared, caching).
Design: Graceful Transformation
Market
- 10-20% of the population in most countries have disabilities. Some
affect Web access.
- Temporary disabilities such as RSI, holiday accidents can affect a very
small company.
- Aging populations (lower vision, hearing, mobility).
- Lots of mobile access users to come!
Law
Refer to WAI Policies Reference
list.
- Australia
- Canada
- Denmark
- France
- Ireland
- Portugal
- United Kingdom
- United States
II. W3C and WAI
- World Wide Web Consortium (W3C)
- W3C hosts the Web Accessibility Initiative (WAI)
- partnership of industry, disability organizations, access research
centers, government
- major sponsors include:
US, European and Canadian governments, IBM/Lotus, Microsoft, Bell
Atlantic
What WAI does
- Accessibility Guidelines:
- Review W3C specifications for accessibility
- Evaluation and Repair Tools
- Education and outreach: Quick
Tips, Movie, ...
- Coordination of Research
III. Principles of Accessible Design
Principles that appear in all three Guidelines:
- Device independence (input and output)
- Graceful transformation
- Alternative equivalent and Metadata
- Context, Orientation, and Notification
- Navigation
- Documentation
Techniques are implementation suggestions, issues, and language-specific
details
Standards and conventions:
- Allow assistive technologies access
- Interoperability promotes accessibility
- Validate or Crash-and-Burn: Don't ignore important information
(ecommerce, contracts, medical decisions).
- Credible design: Well-written pages build confidence in content.
- Innovate new functionalities, but use standard channels since people and
tools rely on them.
IV. Quick Tips, Guidelines and more
WAI produces a range of materials
- W3C Recommendations
- "Technical standards". The Guidelines
- Reference Notes
- Discussion papers on specific technologies - CSS, SMIL, ...
- Education materials
- Quick Tips, flyers, Curriculum ...
- Education resources
- Getting started, Policy
reference, ...
- Images & animations. Use the
alt attribute to describe the function of each visual.
- Image maps. Use client-side
MAP
and text for hotspots.
- Multimedia. Provide captioning and transcripts
of audio, and descriptions of video.
- Hypertext links. Use text that makes sense
when read out of context. For example, avoid "click here."
- Page organization. Use headings, lists, and
consistent structure. Use CSS for layout and style where
possible.
- Graphs & charts. Summarize or use the
longdesc attribute.
- Scripts, applets, & plug-ins. Provide
alternative content in case active features are inaccessible or
unsupported.
- Frames. Use
NOFRAMES and
meaningful titles.
- Tables. Make line by line reading sensible.
Summarize.
- Check your work. Validate. Use tools,
checklist, and guidelines at http://www.w3.org/TR/WAI-WEBCONTENT.
Web Content Accessibility Guidelines
http://www.w3.org/TR/WAI-WEBCONTENT
- W3C Recommendation, WCAG
1.0
- Has a companion Techniques
document.
- Explains to Web site designers how to make accessible Web sites
- Nearly one year old
- Foundation for Authoring Tool & User Agent Accessibility
Guidelines
- Has 14 guidelines, 60+ checkpoints
- Priority/conformance model re-used in ATAG & UAAG
- Comprehensive document, but with simplified checklist

WCAG - hit and myth
Web Content Guidelines are...
- Techniques document in current development
- Modularised by technology (HTML, SVG, SMIL, etc)
- Updating according to deployment
- Browser support increasing
- Guidelines will also evolve
- Generalise for wider range of use - XML, Graphics, etc
- Increase the amount of information in Techniques document
- Using the same process - collaboration of industry, users, expert
research
WCAG hit and myth
Web Content Guidelines are not...
- Requiring text only
- Prohibiting colourful, media-rich pages
- Written solely for english in the USA
- Based on what is easy. (They are based on what is
necessary.)
Authoring Tool Accessibility Guidelines
http://www.w3.org/TR/WAI-AUTOOLS
- All tools for Web Content - images, HTML, database systems, word
processors...
- Both: generation of accessible content and
accessibility of the environment.
- Same Priority, Guidelines, Checkpoints, organization as Web Content
- Companion Techniques document with examples, references, etc
- Evaluations of Authoring software
- W3C Recommendation February 2000
The Authoring Tool Guidelines
- Support all accessibility features of W3C recommendations
- Generate standard markup
- Make sure that no accessibility content is missing
- Provide Methods of checking and correcting inaccessible content
- Integrate accessibility solutions into the overall "look and feel"
- Promote accessibility in help and documentation
- Make the Tool Accessible
Authoring Tools - building the future
- Working with developers
- Have begun evaluating tools
- Building tools, templates, techniques
User Agent Accessibility Guidelines
http://www.w3.org/TR/WAI-USERAGENT
- Emphasis for version 1.0 on common graphic browsers, HTML
- Some focus on mobile devices, multimedia players, ...
- Same Priority, Guidelines, Checkpoints, and Techniques organization
- Looking at:
- Accessible UI, control over style
- Orientation and access to document structure
- Visibility of accessibility information and controls
- Compatibility with assistive technology
- Final release: early Summer 2000 (now a Proposed
Recommendation)
V. Fix this!
While fictional, this page accurately illustrates common practices.
Some things to think about generally:
- Illustrate with images
- Validate!!
- Make large groups of links "skippable"
Fix 1: Ensure Scripts are accessible
- Content must not rely on scripts to provide information.
- Use markup instead of scripts when possible.
- Don't prevent access through browser-sniffing.
Make other scripts accessible:
<a href="javascript:popout('miles')" onmouseover="highlight()">
<img src="blood.gif" alt="earn miles - donate blood"></a>
Becomes
<a href="miles" target="_blank" onfocus="highlight()"
onmouseover="highlight()"><img src="blood.gif" alt="earn miles - donate blood"></a>
Related Checkpoints: WCAG 6.3, 6.4, UAAG 9.1
Improved example
Fix 2: Provide equivalent alternatives
Since text can be rendered visually, as speech, or as braille it helps many
users.
In HTML, provide short functional equivalent text with the "alt"
attribute:
<IMG ... alt="Navigation Bar..." >
<IMG ... alt="Advertising Information" >
<AREA ... alt="More Articles" >
<AREA ... alt="Health Topics" >
Provide content for applets:
<applet code="Lake.class">
<param name="image" content="lh.gif">
<img src="lh.gif" alt="Latest News">
</applet>
Provide long descriptions for complex content (charts, graphs, etc.)
Related Checkpoints: WCAG 1.1, 6.3 ATAG 3.1, 3.3, 3.5
Improved example
Fix 3: Make frames accessible
To provide navigation alternatives, assign titles to frames and add a
"noframes" alternative:
<FRAME ... name="TOC"
title="Table of Contents" >
<FRAME ... name="Home"
title="Home Page" >
<NOFRAMES>
<BODY>
<P><a href="a"><img src="vnav.gif" border=0 usemap="#map" alt="Navigation Bar..."></a>
...
</BODY>
</NOFRAMES>
Related checkpoint: WCAG 12.1
Improved example
Fix 4: Specify colours appropriately
Specify all colours for a colour scheme. If only a background is given it
might be the same as user-specified defaults for a foreground.
Ensure specified colours have sufficient contrast to be read.
body background=bg.gif
becomes
body background="bg.gif" bgcolor="#8e0851" text="white" link="3fa" vlink="5f5"
Don't forget images!
Related Checkpoint: WCAG
2.2
Improved example
Fix 5: Use meaningful link text
To provide information about link targets to users who surf link text only,
write:
<A href="a">
Coping With Asthma's Relentless Attacks</A>
instead of:
Coping With Asthma's Relentless
Attacks:<A HREF="a">Click Here</A>
Related checkpoint: WCAG 13.1
Improved example
Fix 6: Add structure
To convey a logical model other than visually, use markup correctly. For
example:
<B>9 May 1999</B> <IMG src="l1.gif">
becomes:
<H1>9 May 1999
<IMG src="l1.gif" alt="Latest News"></H1>
Related checkpoints: WCAG 3.5, 3.6, ATAG 3.2
Improved example
Fix 7: Use style sheets
- Use CSS instead of background image as color
- Replace text in images with real text.
- Use a style sheet instead of
FONT element / inline
styles
Related checkpoints: WCAG 3.1, 3.3, UAAG 4.17
A much more accessible version
VI. Resources to Get Started
Get Involved!
- Ensure that your Web sites are accessible
- Promote your commitment to accessibility
- Partner with W3C/WAI in promoting awareness
- Demand tools that support accessibility
- Distribute Quick Tips and other
accessibility information
- Participate in development of guidelines
- Join the Protocols and Formats Working Group
VI. Questions and discussion
W3C presentations are archived online at http://www.w3.org/Talks