Web Accessibility

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Web Accessibility
Rick Ells rells_at_cac.washington.edu UW Computing
Communications
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Disability Types

• The major categories of disability types are
• Visual
• blindness, low vision, color-blindness
• Hearing
• deafness
• Motor
• inability to use a mouse, slow response time,
  limited fine motor control
• Cognitive
• learning disabilities, distractibility, inability
  to remember or focus on large amounts of
  information
• From Introduction to Web Accessibilityhttp//www
  .webaim.org/intro/

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Who has disabilities?

• Visual impairment16 (27.4 million) of
  working-age adults have a mild visual difficulty
  or impairment, and 11 (18.5 million) of
  working-age adults have a severe
  visual difficulty or impairment.
• Dexterity impairment19 (31.7 million) of
  working-age adults have a mild dexterity
  difficulty or impairment, and 7 (12.0 million)
  of working-age adults have a severe dexterity
  difficulty or impairment.
• Hearing impairment19 (32.0 million) of
  working-age adults have a mild hearing
  difficulty or impairment, and 3 (4.3 million)
  of working-age adults have a severe hearing
  difficulty or impairment.
• From The Wide Range of Abilities and Its Impact
  on Computer Technology - A Research Study
  Commissioned by Microsoft Corporation and
  Conducted by Forrester Research, Inc., in 2003
  http//www.microsoft.com/enable/research/

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Web accessibility and the law

• 1973 Rehabilitation Act
• Prohibits discrimination on the basis of handicap
  by employers receiving federal contracts or in
  federally assisted programs
• 1990 Americans With Disabilities Act
• Prohibits discrimination on the basis of
  disability in employment, by governmental
  agencies, and in public accommodations
• 1998 Section 508 of the Rehabilitation Act
• Requires Federal departments and agencies to take
  into consideration accessibility when developing,
  procuring, or using electronic and information
  technology http//www.section508.gov/
• By 2001, all Federal Web sites complied with
  requirements

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Washington State and the UW

• UW has long standing policy of providing
  reasonable accommodation for the handicapped
• 2005 Washington State Department of Information
  Services sets guidelines based on Section 508 for
  government and educational Web siteshttp//isb.wa
  .gov/tools/webguide/accessibility.aspx

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Technologies and Strategies

• Assistive Technologies
• Alternative keyboards or switches
• Braille and refreshable braille
• Scanning software
• Screen magnifiers
• Screen readers
• Adaptive Strategies
• Speech recognition
• Speech synthesis
• Tabbing through structural elements
• Text browsers
• Visual notification
• Voice browsers
• From How People with Disabilities Use the Web
• http//www.w3.org/WAI/EO/Drafts/PWD-Use-Web/tools
  

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Device independence

• The Goal Access to a Unified Web from Any Device
  in Any Context by Anyone
• From Device Independencehttp//www.w3.org/2001/d
  i/

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Building in device independence

• Organize content in simple hierarchical structure
  (XML)
• Easier for each device to receive, interpret, and
  display
• Separate presentation from content (CSS)
• Allows separate presentation instructions for
  different devices
• Provide alternatives
• Example Text descriptions of graphics
• Define associations
• Examples Text with form fields, row and column
  labels

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Creating and using accessible content

From Essential Components of Web
Accessibilityhttp//www.w3.org/WAI/intro/componen
ts.php
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Guidelines and Standards

From Essential Components of Web
Accessibilityhttp//www.w3.org/WAI/intro/componen
ts.php
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Basic accessible design

• Keyboard navigable A person with poor sight, no
  sight, or limited dexterity cannot use a mouse.
• Standards-compliant Pages that adhere to
  standards are easier to design assistive and
  adaptive client programs for.
• Makes sense linearly Encountering a Web page
  with a voice browser is a linear process,
  progressing through the content in sequence or
  navigating by the structure of the content. A
  sighted person using a graphic browser can take
  in two-dimensional spatial arrangements of
  content and go directly to any visible part.
• Provides Alternatives Provide alternative text
  for people who cannot see graphics.
• Helps make connections When you can only hear a
  page, it can be hard to tell which text goes with
  which form field or which row and column a table
  cell is in. Simple labeling of text and form
  field pairs and of rows and columns enables
  assistive and adaptive programs to correctly
  present content relationships.
• Has no surprisesNo sudden pop-up windows or
  pages that take the reader away from the page
  they are reading. No links that cannot be tabbed
  to or evoked by pressing the return key.

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10 quick tips to make an accessible Web site

• Images animations Use the alt attribute to
  describe the function of each visual.
• Image maps. Use the client-side map and text for
  hotspots.
• Multimedia. Provide captioning and transcripts of
  audio, and descriptions of video.
• Hypertext links. Use text that makes sense when
  read out of context. For example, avoid "click
  here."
• Page organization. Use headings, lists, and
  consistent structure. Use CSS for layout and
  style where possible.
• Graphs charts. Summarize or use the longdesc
  attribute.
• Scripts, applets, plug-ins. Provide alternative
  content in case active features are inaccessible
  or unsupported.
• Frames. Use the noframes element and meaningful
  titles.
• Tables. Make line-by-line reading sensible.
  Summarize.
• Check your work. Validate. Use tools, checklist,
  and guidelines at http//www.w3.org/TR/WCAG
• From Quick Tips to Make Accessible Web Sites
• http//www.w3.org/WAI/References/QuickTips/Overvie
  w.php

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Poor form
From Creating accessible forms, WebAIM,
http//www.webaim.org/techniques/forms/
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Good form
From Creating accessible forms, WebAIM,
http//www.webaim.org/techniques/forms/
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Caption videos
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Is your Web page accessible?

• Check for standards-based, validated coding
• Evaluate keyboard navigability of the page
• Evaluate coding and page design
• Check for Section 508 compliance using WebXact
  (formerly known as Bobby)

From Accessibility Evaluation Procedure,
AccessibleWeb_at_U, http//www.washington.edu/comput
ing/accessible/accessibleweb/eval_proc.html
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Accessibility evaluation checklist

• Are frames appropriately titled?
• Are ALT tags present and sufficiently equivalent
  to the graphic content?
• Are form elements explicitly associated with
  labels?
• Is information in PDF available in other more
  accessible formats?
• Are all links and navigational elements present
  and contextually appropriate via the keyboard?
• Does the site avoid conveying meaning with color
  alone?
• Are data tables marked up as required?
• Is multimedia content captioned (or if audio
  only, transcribed)?
• Is flickering content avoided?
• Is a skip navigation link present if needed?
• Is the page functional when scripts are disabled?
  
• Is the page functional when style sheets are
  disabled?
• Does link text provide a reasonable description
  of the link target?
• If a page requires a timed response, can users
  request more time?
• From Web Accessibility Rubric, Terry Thompson,
  http//staff.washington.edu/tft/rubric.php

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A flood of new technologies
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Web application model
From Ajax A New Approach to Web
Applicationshttp//www.adaptivepath.com/publicati
ons/essays/archives/000385.php
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Dynamic content
From Ajax A New Approach to Web
Applicationshttp//www.adaptivepath.com/publicati
ons/essays/archives/000385.php
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The promise of better interaction
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Accessible Web applications

• Section 508 Tutorial  Developing Accessible
  SoftwareDemonstrating principles by developing a
  calculator in Visual Basichttp//www.access-board
  .gov/sec508/software-tutorial.htm
• Software Applications and Operating Systems
  (1194.21)Program features that must be contained
  in software for the product to meet Section 508
  standards. http//www.access-board.gov/sec508/gui
  de/1194.21.htm

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Dynamic content

• Accessible DHTML, Mozilla, accessible Web ap
  methods supported by FireFox 1.5 and WindowEyes
  5.5 http//www.mozilla.org/access/dhtml/
• DHTML Accessibility - Fixing the JavaScript
  Accessibility Problem, Rich Schwerdtfeger and
  Becky Gibson, IBM, http//www.csun.edu/cod/conf/20
  05/proceedings/2524.htm
• Client-side Scripting Techniques for WCAG 2.0,
  W3C, http//www.w3.org/TR/WCAG20-SCRIPT-TECHS/

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Is accessible design worth it?

• The handicapped are a valued part of the UW
  community and they are not going away.
• The UW has a national reputation of supporting
  and accommodating the handicapped.
• Your peer developers are already working on this
  problem (lots of opportunities for conferences
  and papers).
• The methods needed here are already common in
  other application software.
• Doing it right could avoid future hassles for the
  UW.
• You, or someone you love, may need adaptive or
  assistive technology someday.
• Its the human thing to do.