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University of Sunderland CDM105 Session 3 Web Authoring Web accessibility A review of some of the current issues affecting Web design in respect to user accessibility
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University of Sunderland CDM105 Session 3 The World Web Wide In 1998, there were in excess of 50 million Web pages with 20,000 new sites being added every day Thus, the Web has grown into a vast information source being used as part of everyday life Technology has progressed –The Web offers a full multimedia experience (e.g. sound, video, interaction, games etc.) A total success ?
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University of Sunderland CDM105 Session 3 Web Accessibility As the Web has become more of a multimedia experience this has restricted access to a large number of users Consider the following user groups: –Users who are visually impaired –Users who are deaf or have hearing impairments –Users with physical or motor disabilities –Users with cognitive/neurological disabilities How does Web design help or hinder these user groups ?
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University of Sunderland CDM105 Session 3 The visually impaired and the Web Blind –Require the use of assistive technology (e.g. screen readers) –Many sites are purely images which do not use the ALT tag are inaccessible Partially Sighted –May require the use of assistive technology (e.g. hardware or software capable of magnifying the size of the screen) –Sites which the font size on pages restricts accessibility to this group of users Colour Blind –Difficulty distinguishing between certain combinations of colours (In the UK 10% male and 1% female are colour blind) –Pages that do not have a high contrast between the background the text can be hard to read
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University of Sunderland CDM105 Session 3 The World Wide Web Consortium - W3C Formed by the creator the Web, Tim Berner-Lee, who is currently the director of the W3C W3C aims to ‘promote interoperability in order to achieve universal access to the Web’ Promotes technologies to take into account the vast differences in cultures, education, ability, material resources and physical limitations of all users on all continents
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University of Sunderland CDM105 Session 3 Aims to prevent a single vendor or operating system being favoured over any others However, it produces only standards It can not enforce them ! Currently has four hundred member organisations The World Wide Web Consortium - W3C
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University of Sunderland CDM105 Session 3 The W3C and users with disabilities In 1997, launched the Web Accessibility Initiative (WAI) The WAI project sets objectives that are designed to ‘promote and provide increased functionality on the Web for individuals with disabilities’ Five main objective areas: –Technology, Tools, Guidelines, Education, Research
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University of Sunderland CDM105 Session 3 The W3C and users with disabilities Technology –conversion of HTML documents into formats that can be used on devices such as Braille bars and speech synthesisers Tools –provide authors with Web authoring tools that support accessibility Guidelines –to aid authors generate accessible pages Education –promote awareness Research –ongoing work to help develop new tools
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University of Sunderland CDM105 Session 3 The LAW and the Web ??? All of you have now created Web pages have you broken any laws ? Could you be taken to court by users who can not access your Web site due to poor site design or neglect for certain user groups ? Many countries now have laws that could be applied to the accessibility of the Web
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University of Sunderland CDM105 Session 3 The Americans with Disabilities Act ADA (1992) It did not specifically address the issue of access to the Web until it was amended in 1996 It does however contain guarantees of “reasonable accommodation” and “effective communication” for people with disabilities in areas of employment, public services, public considerations offered by private bodies and telecommunications providers
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University of Sunderland CDM105 Session 3 The Americans with Disabilities Act ADA (1992) U.S. National Federation of the Blind sued America Online –their Internet service was not accessible An individual (Mr.R.Tamez who is visually impaired) used the act to make the San Fancisco Bay Area Metro change there Web site to make it accessible. “A Web site is like a public building. You open it to the public, and you can’t discriminate against people who can’t get up the stairs” (Mr. R. Tamez)
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University of Sunderland CDM105 Session 3 Other US Acts and Laws The Telecommunications Act of 1996 –Access to telecommunications and related facilities for people with disabilities The Federal Rehabilitation Act –Section 508 ensures access to electronic and information technology is made available to people with disabilities The 1998 Assistive Technology Act –Grants to help development technologies
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University of Sunderland CDM105 Session 3 What about in the UK ? Currently, weaker than in the US The only act that could be applied is the Disability Discrimination Act (DDA - 1995) Emphasises that employers and suppliers of goods, services and facilities provide ‘reasonable adjustment’ to accommodate people with disabilities –remove barriers that may result in discrimination
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University of Sunderland CDM105 Session 3 Example: Creating sites for the Visually Impaired Colour and Text –The end user should always be able to use their browser to override the pages scheme to a more suitable one (e.g. to permit a high contrast scheme, change the font size) Images –Always use ALT or LONDEC (long description; places a d next to the image ) Links –Ensure these are descriptive
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University of Sunderland CDM105 Session 3 Frames –Ensure the NOFRAMES tag is used as assistive technologies such as screen readers and Braille bars can not cope with FRAMES Tables –Now used widely for ‘layout’ on the Web (e.g. Dreamweaver uses them widely) making the page incomprehensible to anyone using assistive technologies –Solution: HTML version 4 provides SUMMARY and ID tags which help screen readers de-code the table Example: Creating sites for the Visually Impaired
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University of Sunderland CDM105 Session 3 Plug-in Technology –Add interactivity (e.g.Shockwave, QuickTime) –Flash can aid accessibility if used to help users (e.g. speech output on rollovers etc.) –However, Nielsen has referred to Flash as ‘a usability disease’ ! –Future releases of Flash are expected to incorporate more accessibility features Example: Creating sites for the Visually Impaired
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University of Sunderland CDM105 Session 3 Testing Web Site Accessibility for Visually Impaired Users Bobby created by the Centre for Applied Special Technology (CAST) provides a Web page validation service –checks compliance with WAI –checks web pages for browser compatibility –unable to analyse JavaScript content http://www.cast.org/bobby/
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University of Sunderland CDM105 Session 3 The W3C validation service THE W3C HTML Validation Service Checks the page conforms to the specifications defined by the W3C. http://validator.w3.org/
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University of Sunderland CDM105 Session 3 Machine Based Tutorial The tutorial session again requires you to read over web based materials and complete the exercises contented within them In the machine based tutorial session you will learn how about the constructs used to make web FORMS and you will make simple online forms. You should also check the accessibility any pages you have created previously in sessions 1 and 2 using Bobby and the W3C validator You should aim to complete the machine based tutorial session 3 before the next lecture.
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