Architecting & Designing
for Accessibility
Misty McLaughlin
Information Architecture &
Design I
October 19, 2004
Accessibility
• Why and What
• Types of disabilities
• Assistive / adaptive technology
• Legislation, policy, standards
• Design techniques
• Testing, simulation and repair tools
• Opportunities to practice
Why?
• 20 million: Americans with disabilities that
seriously affect their use of the Web
• 50%: Americans over 65 with disabilities
• 500-750 million: People with disabilities
internationally
• $690 million: Annual cost to make federal
websites accessible
From “Who Are the Disabled?” and Maximum Accessibility
What is Accessibility?
Some Accessible Design Philosophy
Point of Cohesion
• Same information, same tasks
• Does not depend on a single sense or ability
Points of Contention
• Accessibility v. usability
• Is accessibility a patch or a fundamental
design consideration?
Formal Disabilities
•
•
•
•
Cognitive / learning
Auditory
Motor / physical
Speech
• Visual
- legal blindness
- impaired vision
- color blindness
Quasi-disabilities…
a.k.a. “Access Barriers”
• Slow internet
connection
• Old browser
• Missing plug-ins
• No speakers
• Small display (old
monitors, handheld
devices)
• No mouse
•
•
•
•
•
Age
Language issues
Noisy environment
Eyes or hands busy
Photosensitive
epilepsy
Assistive / Adaptive
Technology
As defined by the Assistive Technology Act of 1998:
“…any item, piece of equipment, or product system,
whether acquired commercially, modified, or
customized, that is used to increase, maintain, or
improve the functional capabilities of individuals
with disabilities.”
“…mediates and decodes the technology
for users with disabilities.”
“…make information devices more accessible.”
Assistive / Adaptive
Technology
Auditory
Closed captioning
Visual
Screen readers & magnifiers,
refreshable Braille display
Alternative keyboard layout &
mouse system
Slow-mo software
Special voice recognition
software
???
Motor /
physical
Speech
Cognitive /
learning
Accessibility Legislation
National
• Americans With Disabilities Act (ADA) – 1990
• Section 508 of the Vocational Rehabilitation Act –
1973
- Requires that electronic and information
technology developed, procured, maintained, or
used by the Federal government be accessible to
people with disabilities.
Statewide
• Chapter 206 of the Texas Administrative Code, the
“Access to Information” Law - 2002
Policy – In-house Rules
• UT Austin’s Web
Accessibility Policy
- Section 508 compliant
- Accessibility policy
link required
- Responsibility
- Testing &
Documentation
Standards
Checklists, guidelines, & practical info
• W3C’s WCAG (Web
Content
Accessibility
Guidelines)
– Over 60 checkpoints
– International
acceptance (EU,
Canada, Australia)
• Section 508 Guidelines
- Applies only to
federal agencies,
legally
- 16 checkpoints
- based on WCAG’s
most critical points
- objective &
measurable
From Maximum Accessibility
Design Considerations
Some rules
• “The ultimate error that any developer
of accessible applications can commit
is to modify the user’s environment.”
--John Paul Mueller, Accessibility for Everybody
• Graceful transformation,
understandability, navigability
--Web Content Accessibility Guidelines, W3C
Visual Style
Color
• Don’t use color to
convey primary
meaning
• High contrast
Font
•Sans-serif
•Relative font size
Images & Multimedia
• Provide a textequivalent to visual or
audio information (alttext or captions)
• If video, captions / alttext should be
synchronized
• Avoid flickering
“The Living Room Candidate,” American
Museum of the Moving Image
Simulation exercise for the non-disabled:
1) Turn your speakers off and watch.
2) Turn your monitor off and listen.
Markup
• Correct, structural
rather than fixed
markup
• Use CSS to control
page elements (but
don’t convey critical
info through CSS)
• Elastic, relative units
Avoid:
• Font tags, fixed pixel
sizes
Quality Content
•
•
•
•
Plain, readable language
Quality descriptions and link text
Clear referents
Avoid jargon and specialized language
unless your audience is insider-only
Can Use If You Do It
Carefully
Image Maps
Data tables
Don’t Do It If You
Can Help It
Images that blink or
flicker
Decontextualized
pop-ups
Graphs and charts
Scripts
Frames
Applets and plugins
Forms
From Maximum Accessibility
Tips
• 1-pixel accessibility
info at the top of your
page
•“Skip navigation” or
“skip to main content”
•Offer alternative stylesheet option
Testing, Simulation & Repair
• W3C’s Web
Accessibility Initiative
(WAI) - comprehensive
list
• * Accessibility Toolbar
(for IE) *
• Evaluating Web Site
Accessibility
(checklists, tips, and
more)
Simulation of www.utexas.edu
appearance for users with diabetic
retinothopy
Best Testing Tool
User testing
with groups
of users
who have
mixed
disabilities
Local Accessibility
Opportunities
• Accessibility Internet Rally
- AIR-Texas
- AIR-University
• UT’s Accessibility Institute
- Free training
- Accessibility research
- Site evaluation and user
testing
• Knowbility Accessible
Technology
- Community training
programs
- Annual accessibility
conference (free to UT
students, faculty & staff)
• Jim Thatcher, Accessibility
Consultant
- Free training
- Site evaluation
References
Clark, Joe. Building Accessible Websites. New Riders, 2002.
Slatin, John and Rush, Sharron. Maximum Accessibility: Making
Your Web Site More Usable for Everyone. Boston: AddisonWesley, 2003.
Mueller, John Paul. Accessibility for Everybody: Understanding
the Section 508 Accessibility Requirements. Berkeley: Apress,
2003.
Thatcher, Jim. Constructing Accessible Websites. San Francisco:
Apress, 2003.
Van Duyne, Douglas and Landay, James and Hong, Jason. The
Design of Sites: Patterns, Principles, and Processes for
Crafting a Customer-Centered Web Experience. Boston:
Addison-Wesley. 2002.
Accessibility Resources Online
Glossary
Toolbar
Resource Center
Course / tutorial
Questions?
Contact m.mclaughlin@mail.utexas.edu.