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Web accessibility Web accessibility and Disability A Practical introduction Robin Christopherson and Curt Holst AbilityNet Adapting Technology • Changing Lives What is web accessibility? “ Web accessibility is about designing sites so as many people as possible can access them effectively and easily, independent of who they are or how they access the net “ Adapting Technology • Changing Lives Web standards Standards Web Content Accessibility Guidelines 1.0 Guidelines created in 1999 to explain how to make websites and intranets accessible to people with disabilities. They are prioritised into three levels: Priority Level 1 - 'Must' or level ‘A’ Minimum Priority Level 2 - 'Should', or level ‘Double-A’ Good practice Priority Level 3 - 'Ought' or level ‘Triple-A’ Best practice Adapting Technology • Changing Lives Who does it affect? 9.8 million people in the UK have a disability under the DDA. The groups that have specific Issues with web and intranet accessibility are: Vision impairment Hearing impairment Motor difficulties Cognitive impairments and literacy ~ Many have more than one disability Adapting Technology • Changing Lives Vision As a very visual medium, the Web presents unique problems to the millions who have low, restricted or no vision. There are 4 broad categories of vision impairment: Colour blindness – red/green impairment most common Mild vision impairment – larger font size, colours Moderate vision impairment – screen magnification, colours Blind/severe vision impairment – screen readers Adapting Technology • Changing Lives Mild vision impairments – Adjust the Browser Adapting Technology • Changing Lives Magnification software Adapting Technology • Changing Lives Key guidelines for mild/moderate visual impairments Do not use colour alone to convey information (level 1) Ensure a consistent and uncluttered page layout (level 2) Avoid using graphics for text (level 2) Choose colours that ensure sufficient background and foreground contrast and avoid combinations of red/green and blue/yellow (level 2/3) Adapting Technology • Changing Lives Key guidelines for mild/moderate visual impairments Ensure all font size definitions are relative -re-sizeable (level 2) Offer a hi-viz skin and/or link to a page explaining how to change colours and font sizes (level 3) Use a clear non-seriffed font such as Arial, Tahoma or Verdana (recommended) Avoid using Flash for text – there are resizing issues (recommended) Adapting Technology • Changing Lives Screen-Reader Users Adapting Technology • Changing Lives Key guidelines blind web users Ensure all images have alt tags - especially links, logos and important pictures. Use empty alt tags (alt=“”) for decorative images (level 1) If you use Flash make sure it works with modern screen readers and provide an accessible alternative for older readers (level 1) If you use frames ensure they have titles and names that make sense - screen readers navigate in and out of individual frames on a page (level 1) Make sure tabular data is coded accessibly – use the correct table header tags for column titles (level 1) Adapting Technology • Changing Lives Key guidelines blind web users Provide transcripts for Multimedia if you use it (level 1) Ensure both JavaScript and Applets work with screen readers – provide alternative content if they don’t. (level 1) Choose text for hyperlinks with care – make sure it makes sense out of context and avoid repetition (level 2) Position labels in forms to the left or above input fields and the right of checkboxes and radio buttons (level 2) Offer a “Skip to content” link to jump over navigation links (level 3) Adapting Technology • Changing Lives Hearing Multimedia, including video and audio clips on the web provide captioning and transcripts. British Sign Language (BSL) users – limited vocabulary for example ‘Marinade’ Provide a glossary of terms Adapting Technology • Changing Lives Motor difficulties People with motor difficulties face challenges when navigating and interacting with web pages. Dexterity, fine motor and coordination difficulties can make using a standard keyboard or mouse difficult. Keyboard and mouse alternatives or voice recognition can be used to navigate and interact with web pages Adapting Technology • Changing Lives Hand/Arm Adaptive technology Alternative Pointing Devices Adapting Technology • Changing Lives Hand/Arm Adaptive technology Alternative Keyboards Adapting Technology • Changing Lives Key guidelines for Motor Difficulties For Keyboard users: If you use flash or scripts make sure pages are useable with the keyboard (level 2) Ensure a logical tabbing order through all page elements (level 3) Use shortcut links – ‘AccessKeys’ for top navigation links (level 3) Limit the number of links on the page (recommended) Adapting Technology • Changing Lives Key guidelines for Motor Difficulties For Mouse users: Graphical or text links should be a decent size(recommended) Avoid graphical or text links in close proximity not 1/2/3 (recommended) Adapting Technology • Changing Lives Cognitive Difficulties and Dyslexia Cognitive impairments include dyslexia, memory impairments and attention deficit disorders. Recommendations: Keep the language clear and avoid jargon (level 1) Use consistent navigation, sitemaps and breadcrumb trails (level 2) Keep movement to a minimum or allow user to it turn off (level 2) Use graphical icons as navigation aids (level 3) Adapting Technology • Changing Lives Cognitive Difficulties and Dyslexia Recommendations continued: Content should be organised logically and clearly (level 3) There should be sufficient spacing between lines, paragraphs or sections, use bulleted lists (recommended) Use a clear non-seriffed font and don’t fully justify text (recommended) Dyslexic web users prefer a beige background (recommended) Adapting Technology • Changing Lives Sources of help Many organisations (such as AbilityNet) offer a wide range of services to help you make your websites and intranets accessible, Including: • Audits, • Training • Site design • Disabled user testing Key resources on the web include: W3C Web accessibility initiative -http://www.w3.org/WAI/ Irish National Disability Association (NDA) http://www.accessit.nda.ie/ Accessify - http://www.accessify.com A List Apart - developer resources - http://www.alistapart.com Adapting Technology • Changing Lives Contact AbilityNet To find out more about AbilityNet’s web services Call: 0800 269545 Visit: http://www.abilitynet.org.uk Email: [email protected] Adapting Technology • Changing Lives