Transcript Presentation - CF Conf Central

How People With Disabilities Use
the Web
Larry G. Hull
Accessibility Engineer
Video: Know Your Users
• Web Accessibility From the Users
Viewpoint
• California State University, Fresno
• http://www.csufresno.edu/webaccess
•
Note: video is open captioned
Video Content
• Users with disabilities demonstrate and
discuss the tools they use and the
problems they face accessing the web
Screen Magnification Software
Screen Reader Software
Refreshable Braille Display
Voice Recognition Software
Objectives
• Know the major disability types
• Become aware of the perspectives of
individuals with disabilities
• Understand how people with disabilities
use the web
Screen Magnification Tips - 1
• Text high in contrast against
background
• Don’t use drop shadows or blurry edges
• Don’t use script style or fancy fonts
• Avoid scrolling or moving text
Screen Magnification Tips - 2
• Use standard menu locations
(Left menus work especially well)
• Avoid overly large images
• Don’t use soft-focus or blurry images
Screen Reader Tips - 1
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Include a skip menu link at top of page
Add alt text for graphics
Title frames
Use label to identify entry boxes in
forms
• Limit the number of links on a page
Screen Reader Tips - 2
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Limit the number of links on a page
Don’t automate the selection of a link
Don’t automatically refresh a page
Be sure link text is descriptive. I.e., links
need to be understandable when read
separately from the page content
Screen Reader Tips - 3
• Don’t refer to buttons by their color or by
the image (e.g., green palm tree)
• Avoid pop up windows if possible
• Include a text warning that clicking a link
will open the page in a new window
• Provide a link (e.g., button) to close a
new window
Voice Recognition Tips - 1
• Alt text for menu buttons must match
the text on the button exactly
• Keep alt text short and simple
(does not conflict with screen reader tip
that links be descriptive)
• Links must be visible, not requiring a
mouse roll over to be seen
Voice Recognition Tips - 2
• Place navigation links and forms at the
top of the page so they are visible
without scrolling
(provide a jump to content, a skip menu)
• Limit scrolling by avoiding long pages
(or provide a table of contents with links
that jump to content not visible)
Visual Disabilities
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Blindness
Legally Blind
Low Vision
Color Blindness
Do you use assistive technology to
overcome a visual disability?
Hearing Disabilities
The web is a visual medium...or is it?
• Video, audio, and multimedia content is
becoming more and more common
• Captioned audio is unfortunately still
almost nonexistent on the web
• Provide transcripts for audio clips
• Provide synchronous captioning for
video clips
Motor Disabilities
Spinal cord injury
Cerebral palsy
Multiple sclerosis
Arthritis
Essential Tremor
Lost or damaged limb(s)
Muscular dystrophy
Spina bifida
Parkinson's
Lou Gehrig's Disease
Key Motor Disabilities Concepts - 1
• Users may not be able to use a mouse
Make all functions available from keyboard
• Users may not be able to control the
mouse or the keyboard well
Make pages error-tolerant (e.g. ask "are
you sure you want to delete this file?")
Do not create small links or moving links
Key Motor Disabilities Concepts - 2
• Voice-activated software can replicate
mouse movement, but not as efficiently
as keyboard functionality
Make all functions available from the
keyboard
• Users may become fatigued using "puffand-sip" or similar technologies
Provide (visible) skip over menus or other
lengthy content
Cognitive Disabilities
• Someone with a cognitive disability has
greater difficulty with one or more types
of mental tasks
• Learning disabilities
• Dyslexia
• Attention Deficit Hyperactivity Disorder
• Brain injury
• Genetic diseases
Degrees of Cognitive Disabilities
• Profound cognitive disability
Needs assistance with nearly every aspect
of daily living
Unable to access much web content
• Less severe cognitive disabilities
(e.g., minor learning disorder)
May function quite adequately
Able to access well designed web content
Techniques for Effective
Communication - 1
• Keep site navigation simple, clear and
consistent
• Create structure in documents adding:
 Headings
Bulleted lists
Numbered lists
Definition lists
Techniques for Effective
Communication - 2
• Highlight by changing font, adding style,
or using background (rollover) color
• Simplify layouts as much as possible
- but no simpler
• Keep navigational schemes as
consistent as possible
Techniques for Effective
Communication - 3
• Group textual information under logical
headings
• Organize information in manageable
"chunks."
• Where appropriate, supplement text
with illustrations or other media, and
vice versa
Don’t forget to provide alt text and
transcripts as needed
Awkward Age of Computing
• As U.S. population ages, the number of
people with impairments is increasing
• Technology can mitigate the effects of
their changing physical abilities
• Windows XP accessibility features
www.microsoft.com/enable/aging/tips.aspx
A Screen Too Far
• Can't see text and objects clearly?
Use large icons
Increase or decrease font size of Web
pages
Built-in Bifocals
• Trouble seeing things close up?
Turn on and use Magnifier
Opens a floating window
Enlarges different parts of the screen
Lights, Camera, Action
• Dexterity issues slowing things down?
Use speech recognition features
• Office XP
• Office 2003
Tune Out, Tune In
• Alert & audible notification problems?
Turn on SoundSentry
Get visual warnings for system sounds
Use Windows XP to display closed
captions
Talk To Me
• Alert & audible notification problems?
Turn on and use Narrator
Converts text and captions to speech
Next step: screen reader
Cursor in a Haystack
• Search for cursor or mouse pointer?
Use Cursor Options to change cursor size,
appearance, width, color, or blink rate
Use Control Panel mouse setting to modify
pointer
Loosing Your Grip
• Mouse pointer control problems?
Use MouseKeys
Transfer mouse functions to numeric
keypad
All Together Now
• Key Combinations Difficult?
Use StickyKeys
Press keys sequentially not simultaneously
All Shook Up
• Tremors or stiff fingers?
Use FilterKeys
Ignore brief or repeated keystrokes
Slow down the repeat rate
Easy on the Eyes
• Indistinct or fuzzy images?
Choose screen resolution
Choose a high contrast color combination
to improve screen resolution
Turn on XP Accessibility
• Enabling Sticky Keys
Start / Settings / Control Panel / Accessibility
If accessibility icon is missing, install
accessory
• Enabling Mouse Keys
Start / Settings / Control Panel / Accessibility
Uses the Num Lock part of keyboard
Mouse Keys
Diagram Mapping Operations to Keys
Conclusion
• Design for users with disabilities
Understand how people with disabilities
use the web
Employ relatively simple techniques that
increase accessibility
• Result is a more usable web site for all
• As always, there are specific issues and
problems that can also be addressed