How People With Disabilities Use

spectacularscarecrowAI and Robotics

Nov 17, 2013 (3 years and 8 months ago)

56 views

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


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


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


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


Lost or damaged limb(s)

Cerebral palsy


Muscular dystrophy

Multiple sclerosis


Spina bifida

Arthritis



Parkinson's

Essential Tremor


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 "puff
-
and
-
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