Birkbeck University of LondonBusiness Workshop

Web Accessibility for All Janet Billinge

© 2001-2007 Copyright Janet Billinge Includes some slides derived from Design for All

© Netskills, Quality Internet Training, University of Newcastle

Topics

Disability and the web Disability types Design considerations

Web standards and the law Strategies

Disability and the web

8.5 million adults registered disabled in the UK 14% of the population Not all disabilities affect web usage

2 million people are blind or visually impaired The web improves access to services for some

disabled users BUT few sites are fully accessible NO right answer to design problems as some

accessibility requirements conflict Understanding the problems is the first step

to better design

Disability Types

Disability Types Visual Hearing Motor Learning Cognitive Photo-epilepsy Technological

Visual Disability (1): Blind Screen readers [JAWS (Kyle video), IBM HPR,

Window Eyes…] Output speech and/or Braille (for deaf/blind) Interprets text only Keyboard only Navigate using list of headings, links…

Design considerations Well-structured HTML Text descriptions for non-text elements Link text that is meaningful out of context Keyboard only access and shortcut links to skip

navigation plus Tab/Shift Tab through links using JAWS Design pages that ‘linearise’ and have chunks of

content

Visual Disability (2) Low vision

Screen magnifiers - e.g. Zoom Text

Design considerations Avoid images including text High contrast between text

and background, images… Place images close to

associated text Avoid need to scroll

horizontally

Visual Disability (3) Colour blindness

Design considerations Do not rely on colour alone to

convey information

Hearing Disability Use of multimedia (audio/video)

increasing Sign-language users

English is a second language Design considerations

Text transcripts for audio Synchronous captioning for video Clear simple concise English

Motor Disability Accident, arthritis, ME, RSI, elderly… Alternative input devices

Ergonomic keyboard, tracker ball Mouth stick or head wand with keyboard Single-switch access, sip and puff switch Microphone & voice recognition software

Design Considerations Avoid need for fine motor skills Keyboard only access Links to skip navigation and chunks of content Take account of fatigue

Learning Disability: Dyslexia

15-20% of population Visual processing problems

Object recognition Visual concentration Over-sensitivity to light

Recognising and sequencing letter sounds Reduced reading speed Difficulties with spelling and writing

Short term memory and sequencing Easily lost in web sites Forget backwards navigation

Dyslexia: Design Considerations

Navigation - simple and intuitive Content - broken into chunks Text formatting

Use sans-serif fonts Avoid underlining or CAPITALISATION Avoid changes in text spacing (fonts, double-justify) Avoid use of bold/italic (even for headings)

Support text with supplemental images Page background

Enable user setting for background colour (lilac?) Avoid background images

Customisation via style sheets http://www.dyslexia.com/qaweb.htm

Cognitive Disability Accident, stroke, autism, dementia,

Downs syndrome… Problem of effective communication Design considerations

Clear, simple and consistent navigation Clear and simple writing Supplemental media (images,

audio/video…)

Photo-epilepsy Design considerations

Blinking and moving content Alert users before automatic

display

Technological Disability Older browsers don't support current

W3C recommendations HTML (accessibility features) Cascading Style Sheets (CSS)

Monitors Size and resolution

(640x480, 800x600, 1024x768) Monochrome

Slow modem connection Users may turn off images, multimedia… Reluctance to download large files, plug-ins…

Web standards and the law

Why bother with accessibility? Because you should - ethical, inclusiveness Because you can Because it will benefit you …

by including more potential clients/customers/students

by enhancing the "user experience" for everyone Because it’s a legal requirement

Disability Discrimination Act, 1995 Special Educational Needs and Disability Act

(SENDA), 2002

Usable and Accessible - what does this mean? Web pages should be usable AND accessible Usability:

"is the quality of a system that makes it easy to learn, easy to use, easy to remember, error tolerant, and subjectively pleasing".

Jakob Nielsen, www.useit.com 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 Web Usability is about happier and more efficient

users Accessibility is about increasing number of users

W3C Recommendations W3C Worldwide web consortium

co-ordinates development of web technologies develops specifications, guidelines, standards,

software and tools W3C Web Content Accessibility Guidelines

(WCAG) WCAG for beginners Fourteen guidelines organised into three priority

levels Priority 1 (Level A) MUST be met Priority 2 (Level AA) SHOULD be met Priority 3 (Level AAA) MAY be met

Overview of SENDA Disability is ‘physical or mental impairment

effecting ability to carry out normal day-to-day activities’

Discrimination occurs if disabled students have a substantial disadvantage. [May be justifiable in some circumstances - maintaining academic standards, cost…]

Organisations should make reasonable adjustments

Adjustments should be anticipatory UK Policies http://www.w3.org/WAI/Policy/#UK/

Legislation Around the World Most countries in Europe adopting

variants of WCAG U.S.A.

Adopted Section 508 Subset of WCAG, similar to Priority 1

Omits some WCAG guidelines Contains some additional guidelines Some guidelines are more specific

www.jimthatcher.com/sidebyside.htm

ISO Special Working Group on Accessibility Extending ISO/DIS 9241 ‘Ergonomics

of human-system interaction – Guidance on software accessibility’

SWAG Home Page Target publication date March 2007

British Standards and Accessibility PAS 78 Download ONE copy of Guide

to good practice in commissioning accessible websites from Disability Rights Commission or purchase PAS 78 from BSI Standards

Strategies

StrategiesA. Provide alternative text only site

Limited web experience Targets vision-impaired users Secondary sites may be poorly maintained

B. Dynamic conversion to text only Betsie (BBC Education Text to Speech Internet Enhanc

er) Free Perl script Still limited web experience; targets vision-impaired

users Needs good HTML

C. Design-for-all (Universal Design in U.S.A.) Normally preferred approach

Corporate strategy Develop an accessibility strategy consider:

New materials / legacy materials Corporate site / intranet and e-learning materials Restrictions / staff training

Plan your site Research user needs Design your site, keep design FLEXIBLE

Use advisory service TechDis http://www.techdis.ac.uk/

Usability/Accessibility testing Implement standards XHTML/CSS and WCAG

Summary

Accessible design is a legal requirement A wide range of disabilities affect web

usage Each disability has specific requirements Design-for-all strategy is recommended

where feasible W3C provide guidelines Everyone benefits from accessible

design!