How People With Disabilities Use the Web

Larry G. HullAccessibility 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 webScreen Magnification SoftwareScreen Reader Software Refreshable Braille DisplayVoice 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 livingUnable 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: HeadingsBulleted listsNumbered listsDefinition 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 iconsIncrease or decrease font size of Web

pages

Built-in Bifocals

• Trouble seeing things close up?

Turn on and use MagnifierOpens a floating windowEnlarges 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 SoundSentryGet visual warnings for system soundsUse Windows XP to display closed captions

Talk To Me

• Alert & audible notification problems?

Turn on and use NarratorConverts text and captions to speechNext 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 MouseKeysTransfer mouse functions to numeric

keypad

All Together Now

• Key Combinations Difficult?

Use StickyKeysPress keys sequentially not simultaneously

All Shook Up

• Tremors or stiff fingers?

Use FilterKeysIgnore brief or repeated keystrokesSlow down the repeat rate

Easy on the Eyes

• Indistinct or fuzzy images?

Choose screen resolutionChoose a high contrast color combination

to improve screen resolution

Turn on XP Accessibility

• Enabling Sticky KeysStart / Settings / Control Panel / AccessibilityIf accessibility icon is missing, install

accessory

• Enabling Mouse KeysStart / Settings / Control Panel / AccessibilityUses the Num Lock part of keyboard

Mouse Keys

Diagram Mapping Operations to Keys

Conclusion

• Design for users with disabilitiesUnderstand how people with disabilities

use the webEmploy 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