Web Accessibility Basics

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Web Accessibility Basics

• Jim Doran
• Johns Hopkins University

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What is Web Accessibility?

• The power of the Web is in its universality.
  Access by everyone regardless of disability is an
  essential aspect. -- Tim Berners-Lee, W3C
  Director and inventor of the World Wide Web

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Making Accessible Sites

• The web was designed to be used without a mouse
  and without eyes (if necessary).
• We are either making new web sites, or updating
  old web sites.

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Why bother at all?

• Legal Obligation
• People with Disabilities make up about 15 of the
  population
• More efficient and can save money
• Its actually better for people WITHOUT
  disabilities

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Types of Disabilities

• Deaf, hard-of-hearing, hearing-impaired
• Blind, visually-impaired, low-vision
• Mobility-impaired
• Learning-disabled

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Types of Assistive Technologies

• Screen readers, Braille displays
• Keyboard guards and overlays
• Slow keys and onscreen keyboards
• Replacement mice (foot switches, gigantic
  trackballs)
• Switches and scanning software (blow straws, knee
  triggers)
• Captioning (audio descriptions)

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The Rules

• Web Content Accessibility Guidelines WCAG
  authored by the W3s Web Accessibility
  Initiative, or WAI, has been adapted by much of
  the European Union and is the legal standard in
  many countries.
• See http//www.w3.org/WAI/

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WCAG Priority Levels

• Priority 1
• A Web content developer must satisfy this
  checkpoint. Otherwise, one or more groups will
  find it impossible to access information in the
  document. Satisfying this checkpoint is a basic
  requirement for some groups to be able to use Web
  documents.
• Priority 2
• A Web content developer should satisfy this
  checkpoint. Otherwise, one or more groups will
  find it difficult to access information in the
  document. Satisfying this checkpoint will remove
  significant barriers to accessing Web documents.
• Priority 3
• A Web content developer may address this
  checkpoint. Otherwise, one or more groups will
  find it somewhat difficult to access information
  in the document. Satisfying this checkpoint will
  improve access to Web documents.
  (http//www.w3.org/TR/WAI-WEBCONTENT/full-checklis
  t.html)

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WCAG Versions

• WCAG 1.0, WCAG 2.0

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Section 508

• Part of Rehabilitation Act of 1973, intended to
  end discrimination against people with
  disabilities.
• Section 508 became law on June 21, 2001.
• Equal or Equivalent Access to Everyone
• Based on WCAG priority level 1

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Which should we use???

• That depends.
• Lets compare

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Thoughts

• Some responsibility lies with the user to have
  up-to-date tools and resources.
• 100 Accessibility is not always possible
• Everyone uses the web/user agents/technology
  differently
• Equivalency is the goal
• Common sense is required
• This is an iterative process

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Testing for Accessibility

• Testing requires a combination of software tools
  (algorithmic) AND human judgment (judgment).
• What about usability? Dont make me Think.

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Software

• Watchfires Bobby
• InFocus from SSB Technologies 1795 for corporate
  customers
• The LIFT Machine from UsableNet 999
• WebKing from Parasoft
• WebXM from Watchfire
• More at Jim Thatchers site and here

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Tools of our trade

• Firefox Web Developer by Chris Pederick
• Html Validate by Marc Gueury
• DreamWeaver CS3
• http//validator.w3.org/
• http//jigsaw.w3.org/css-validator/
• http//www.cynthiasays.com/
• JAWS

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Web Standards

• Standards are repeatable, measurable and testable
  specifications that can be used as normative
  technical requirements.
• On to part two CSS basics