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Accessibility Accessibility validators http://www.w3.org/WAI/ER/tools/ Different standards set by government, country and industries. Visually Impaired Color Blind Blind People having difficulty viewing images need alternatives to help them understand what is on the web page Hearing Impaired If web site uses sound consider an alternative such as text to assist. Physically Impaired People unable to use the mouse http://accessites.org/site/2007/03/i-saw-a-mouse-where/ Cognitive and Neurological Impairments Considerations include logical easy to understand navigation Certain animations and flashing can trigger seizures Special Populations and Web Site Design Adaptations Mobile Phones Low Bandwidth Users in a noisy environment Users in a dangerous environment Users driving ESL Older adults Approximately 10-20% of people have some form of impairment Ecommerce sites lose business Legal requirements set by the government Some web design projects must meet standards and be accessible if it is gov work See below for guidelines based on country http://www.w3.org/WAI/Policy/ Sample countries include: Australia France Hong Kong Spain UK New Zealand India Accessibility Groups W3C Web Content Accessibility Guidelines 1.0 For web designers Effective 1999 14 guidelines and 90 checkpoints Authoring Tool Accessibility Guidelines 1.0 For software developer products User Agent Accessibility Guidelines 1.0 For web browser manufacturers Sample checkpoints from W3C http://www.w3.org/TR/WCAG10-CORETECHS/#text-equivalent Structure vs. Presentation Text equivalents Provide a text equivalent for every non-text element (e.g., via "alt", "longdesc", or in element content). This includes: images, graphical representations of text (including symbols), image map regions, animations (e.g., animated GIFs), applets and programmatic objects, ASCII art, frames, scripts, images used as list bullets, spacers, graphical buttons, sounds (played with or without user interaction), stand-alone audio files, audio tracks of video, and vide Quick test! A good test to determine if a text equivalent is useful is to imagine reading the document aloud over the telephone. What would you say upon encountering this image to make the page comprehensible to the listener? Navigation Create a style of presentation that is consistent across pages. [Priority 3] 13.4 Use navigation mechanisms in a consistent manner. [Priority 2] 13.5 Provide navigation bars to highlight and give access to the navigation mechanism. [Priority 3] 13.3 Provide information about the general layout of a site (e.g., a site map or table of contents). [Priority 2] 13.7 If search functions are provided, enable different types of searches for different skill levels and preferences. [Priority 3] 13.2 Provide metadata to add semantic information to pages and sites. [Priority 2] Level 'A' -- All Priority 1 checkpoints are satisfied. Level 'Double-A' -- All Priority 1 and 2 checkpoints are satisfied. Level 'Triple-A' -- All Priority 1, 2, and 3 checkpoints are satisfied. The US Government has endorsed the W3C Web Content Accessibility Guidelines by requiring that all federal Websites and sites that are under a federal contract must comply with the guidelines. More information can be obtained from Section 508. Some tools to help in design http://sixrevisions.com/webstandards/accessibility_testtools/ Test: Close eyes and listen instead of reading WebAnyWhere http://webanywhere.cs.washington.edu/wa.php Sample video of use Accessibility Color Wheel http://gmazzocato.altervista.org/colorwheel/wheel .php Contrast Ratio Firefox Extension to Analyze color on Page http://juicystudio.com/article/colour-contrastanalyser-firefox-extension.php Arguments Debate Accesibility Sample Sites built for accessibility http://htmlhelp.com/design/accessibility/myths.ht ml http://accessites.org/site/ Subscribe to newsletter updating accessibility issues http://www.d.umn.edu/itss/support/Training/On line/webdesign/webdev_listserv.html Resources http://www.d.umn.edu/itss/training/online/web design/accessibility.html
