Accessibility

							          Accessibility
Hugh Lunnon, Jo Castle and
          Aidan McGinley
What is Accessibility?
An accessible product or service is one
 which can be used by all its intended
 users
Accessibility is most commonly discussed
 in relation to people with disabilities
Accessibility barriers occur when the
 design of the technology fails to allow for
 the variations in users' abilities.
Accessibility goals
 All users are able to perceive and understand
  the controls, instructions and outputs
 All users are able to reach and manipulate the
  controls, inputs and outputs
 The user interface is consistent across functions,
  devices and repeated use
 For users who still cannot use the service, an
  equivalent alternative service is available
Web Accessibility
 Web sites and applications
  that people with disabilities can perceive, understand,
   navigate, and interact with;
 Web browsers and media players
  that can be used effectively by people with disabilities,
   and
  that work well with assistive technologies that some
   people with disabilities use to access the Web;
 Web authoring tools, and evolving Web
  technologies
  that support production of accessible Web content and
   Web sites, and that can be used effectively by people
   with disabilities.
Impact of the Web on People with
Disabilities
 The Web is becoming a key resource for:
    news, information, commerce, entertainment,
    classroom education, distance learning,
    job searching, workplace interaction,
    civic participation, government services.
 It is displacing traditional sources of information and
  interaction --
    schools, libraries, print materials, discourse of the workplace;
    some of the traditional resources were accessible; some not.
 An accessible Web means unprecedented access to
  information for people with disabilities.
Web Accessibility is a Cross-Disability
Issue
 Examples of design requirements for people with different kinds of
  disabilities include:
 Visual:
     described graphics or video;
     well marked-up tables or frames;
     keyboard support, screen reader compatibility;
 Hearing:
     captioning for audio, supplemental illustration;
 Physical, Speech:
     keyboard or single-switch support;
     alternatives for speech input on voice portals;
 Cognitive, Neurological:
     consistent navigation, appropriate language level;
     illustration; no flickering or strobing designs
Accessibility Contributes to Universal
Design (Design for All)
 Accessible Web design can contribute to better design for other users:
 Multi-modality (support for visual, auditory, tactile access) benefits users of:
     mobile phones with small display screens, Web-TV, kiosks.
 Multi-modality increases usability of Web sites in different situations:
       low bandwidth (images are slow to download);
       noisy environments (difficult to hear the audio);
       screen-glare (difficult to see the screen);
       driving (eyes and hands are "busy").
 Redundant text/audio/video can support:
     different learning styles; low literacy levels; second-language access.
 Style sheets can support:
     more efficient page transmission and site maintenance.
 Captioning of audio files supports:
     better machine indexing of content; faster searching of content.
Tips for Accessible Websites
 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
Tips for Checking the Accessibility of
Your Website
 Turn off graphics & sounds
 Check the contrast by viewing the page in
  greyscale
 Turn off style sheets
 Turn off scripts, applets, or other programmatic
  objects
 Use the largest font size allowed by a browser
 Use Text based browser like Lynx
  (http://lynx.browser.org)
Designing Accessible User Interfaces

Points to consider
  Obstacles to Accessibility
  Impact on system design
  Access Technologies
Design guidelines
  Overview
  Examples
  Issues and Trade-offs
Design Guidelines
Obstacles to Accessibility

Disabilities
  Visual impairments & blindness
  Hearing
  Cognitive
  Physical
  Neurological
Obstacles to Accessibility (2)
Technological
  Lack of technological updates
  Slow processing times
Environmental
  Noisy surroundings
  Non-hands free environment
Other
  e.g. Not operating in the users natural language
Impact on System Design

Problem: Encountered when sites are:
  Mainly text-based
  Mainly graphics-based
  Provide information in purely audible format
  Rely on certain hardware usage
  Rely on up-to-date technology
  Have fixed text and colour schemes
Impact on System Design

Solution:




 PROVIDE ALTERNATIVES!
Access Technologies
Alternative methods of system input/output
  Screen magnifiers
  Screen readers/Speech synthesizers
  Braille devices
  Alternative keyboards
  Speech recognition software
Work with these when designing user
 interface & content
Design Guidelines

Main Aims
  Highlight different user contexts
  Show alternative ways of expressing content
  Ensure graceful transformation
  Show ways to increase ease of navigation and
   understanding
Design Guidelines (taken from W3C)
1. ‘Provide alternatives to auditory & visual
   content’
2. ‘Don’t rely on colour’
3. ‘Use mark-up & style sheets & do so properly’
4. ‘Clarify natural language usage’
5. ‘Create tables that transform gracefully’
6. ‘Ensure that pages featuring new technologies
   transform gracefully’
7. ‘Ensure control of time sensitive content
   changes’
Provide alternatives to auditory & visual
content
 Serve same
  purpose as original
  format
   Textual descriptions
    of images and
    navigation buttons/
    charts and diagrams
   Textual descriptions
    of auditory content
   Non-textual
    equivalents
Design Guidelines (taken from W3C)
1. ‘Provide alternatives to auditory & visual
   content’
2. ‘Don’t rely on colour’
3. ‘Use mark-up & style sheets & do so properly’
4. ‘Clarify natural language usage’
5. ‘Create tables that transform gracefully’
6. ‘Ensure that pages featuring new technologies
   transform gracefully’
7. ‘Ensure control of time sensitive content
   changes’
Ensure control of time sensitive content
   changes
 Moving
 Blinking
 Scrolling
 Auto-updating content
Ensure control of time sensitive content
changes
 Moving                   As yet user agents do
 Blinking                  not provide control
 Scrolling                 mechanisms for this
                            kind of feature
 Auto-updating content

 Distracting
 Hard to read/interact
  with
Design Guidelines (taken from W3C)
1. ‘Provide alternatives to auditory & visual
   content’
2. ‘Don’t rely on colour’
3. ‘Use mark-up & style sheets & do so properly’
4. ‘Clarify natural language usage’
5. ‘Create tables that transform gracefully’
6. ‘Ensure that pages featuring new technologies
   transform gracefully’
7. ‘Ensure control of time sensitive content
   changes’
Design Guidelines (taken from W3C)
8. Ensure direct accessibility of embedded
    user interfaces
9. Design for device independance
10. Use interim solutions
11. Use W3C technologies & guidelines
12. Provide context & orientation information
13. Provide clear navigation mechanisms
14. Ensure documents are clear & simple
Design Guidelines

Main points
  Provide alternative ways of expressing
   information
  Do not rely on any one format/ technology
  Work with existing access technology
  Make everything as clear and simple as
   possible
Issues & Tradeoffs

Trade offs of guideline compliance
  3) Sacrifice flexibility of mark up language
  6) Limitations on use of new technologies
  11) Non-W3C technology = PDF
  14) Increased standardisation of web =
   decreased innovation and design
Issues & Tradeoffs

 Issues
   7) and 10) Responsibility Issues
   If many alternatives are provided, all must be
    updated
   Can be time consuming and costly to
    implement accessibility
      More costly to add to an existing site than
       develop in from start
   Improved visitor experience
   Increased Customer Base
Solutions
Solutions
 Website Assessment
  Lynx
  Booby


 Accessibility helpers
Tesco.com




 First link on a text browser is to Tesco Access
 Text-based site for slow connections, old
  browsers and people with accessibility issues
 Fully opened by lynx, very few issues with bobby
news.bbc.co.uk
 Another site with a text-
  only link at the top
 Also has a ‘skip to main
  content’ link
   Lessens problems with visual
    impairments and the browsing
    paradigm
 Allows non-sited people to
  view news as well as sited
  people
Betsie
 BBC also has Betsie
    BBC Education Text to
     Speech Internet Enhancer
    Turns any browser into a
     hi-visibility, customisable,
     text-only browser
    BBC sites optimised for
     betsie
    Changeable font, size,
     colours and so on.
    Screen reader
     enhancements
Panasonic myCinema@home




 Very good looking site
 Absolutely NOTHING for text-only browser
     Not even ‘this site will not work without internet explorer’
     Very poor page – visually impaired user wouldn’t know if it had simply not
      finished loading or was broken
 Other pages have long, standard header
     16 pages of header on lynx before any detail
     User not sure whether or not the page has moved on from the last one.
Denon.co.uk
 Site inaccessible due to
  imagemap
    Text-only browser can
     open frames with some
     success
    However the main links
     are contained within an
     imagemap with no
     alternative text
    Site written by a German
     company, so all errors
     (site does not support
     frames, 404 and so on)
     are in German
Things to remember

Text-only pages
Check site with bobby and a text-only
 browser
Alternative text for images
Even if your product is unsuitable for a
 visually impaired person (DVDs, books),
 they might be buying for someone else
If in doubt seek outside help
Software

Accessibility products often use MS
 standards to determine what is on the
 screen of an application
Problems arise with incompatibility
  Lotus notes compared to outlook
Ensure compatibility with Microsoft to help
 ease of use for a disabled person.
Accessibility Products

Several products available to help
 disabled people access the web better
  Screen readers
  Braille Displays
  Magnifying and high-contrast tools for those
   with low site
These all help, but only if a
 website/product allows it
Braille Displays




 Allow blind people to read what is on screen
 Hundreds of ‘pins’ rise and fall to represent what
  is on-screen in the form of braille
 Not cheap – typical setup costs in the region of
  £10,000
Dictation Software
Works by turning the text on-screen into
 synthesized voice
Needs no special hardware – simply a
 soundcard and a speaker/microphone
User can control the pc with verbal
 commands
Needs ‘training’ in order to work well
Several packages available at a
 reasonably low price – from £50
Conceptual model

Web is based on browse and explore
 conceptual model
This model is based on sight
Blind people will never be able to use the
 net as quickly as full-sighted people
Other models are more suited to lesser-
 sighted people – for instance command
 model
Conclusion
Web helps disabled people to achieve
 independence
Accessibility is important
Lots of design guidelines and help
 available
Keep all prospective users in mind
Some high-profile websites and software
 packages still have poor accessibility
Some products available to help
References
 Sites we used included:
    W3C (World Wide Web Consortium)
        (http://www.w3.org)
    Irish National Disability Authority
        (http://accessit.nda.ie)
    RNIB (Royal National Institute of the Blind)
        (http://rnib.org)
    Web Accessibility Initiative
        (http://www.w3c.org/WAI/)
    IBM able website
        (http://www.ibm.com/able)
    Lynx Text-Based web browser
        (http://lynx.browser.org/)
    Bobby webpage layout validator
        (http://bobby.cast.org)
    Betsie Website->text only translator
        (http://www.bbc.co.uk/education/betsie/)