How People With Disabilities Use the Web Larry
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 üScreen Magnification Software üScreen Reader Software üRefreshable Braille Display üVoice 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 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 üMake all functions available from keyboard • Users may not be able to control the mouse or the keyboard well üMake pages error-tolerant (e. g. ask "are you sure you want to delete this file? ") üDo 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 üMake all functions available from the keyboard • Users may become fatigued using "puffand-sip" or similar technologies üProvide (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 üNeeds assistance with nearly every aspect of daily living üUnable to access much web content • Less severe cognitive disabilities (e. g. , minor learning disorder) üMay function quite adequately üAble to access well designed web content
Techniques for Effective Communication - 1 • Keep site navigation simple, clear and consistent • Create structure in documents adding: ü Headings üBulleted lists üNumbered lists üDefinition 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 üDon’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? üUse large icons üIncrease or decrease font size of Web pages
Built-in Bifocals • Trouble seeing things close up? üTurn on and use Magnifier üOpens a floating window üEnlarges different parts of the screen
Lights, Camera, Action • Dexterity issues slowing things down? üUse speech recognition features • Office XP • Office 2003
Tune Out, Tune In • Alert & audible notification problems? üTurn on Sound. Sentry üGet visual warnings for system sounds üUse Windows XP to display closed captions
Talk To Me • Alert & audible notification problems? üTurn on and use Narrator üConverts text and captions to speech üNext step: screen reader
Cursor in a Haystack • Search for cursor or mouse pointer? üUse Cursor Options to change cursor size, appearance, width, color, or blink rate üUse Control Panel mouse setting to modify pointer
Loosing Your Grip • Mouse pointer control problems? üUse Mouse. Keys üTransfer mouse functions to numeric keypad
All Together Now • Key Combinations Difficult? üUse Sticky. Keys üPress keys sequentially not simultaneously
All Shook Up • Tremors or stiff fingers? üUse Filter. Keys üIgnore brief or repeated keystrokes üSlow down the repeat rate
Easy on the Eyes • Indistinct or fuzzy images? üChoose screen resolution üChoose a high contrast color combination to improve screen resolution
Turn on XP Accessibility • Enabling Sticky Keys üStart / Settings / Control Panel / Accessibility üIf accessibility icon is missing, install accessory • Enabling Mouse Keys üStart / Settings / Control Panel / Accessibility üUses the Num Lock part of keyboard
Mouse Keys Diagram Mapping Operations to Keys
Conclusion • Design for users with disabilities üUnderstand how people with disabilities use the web üEmploy 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
- Slides: 35