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  1. Presentation On WEB ACCESSIBILITY Submitted by : Shivani Sachdeva
  2. CONTENTS • What is web accessibility? • Why web accessibility? • Disability Statistics • Types of Disabilities • WCAG 2.0 • Accessibility Principles • Guidelines • Essential Component of Web • Implementation Cycle • Accessibility Checker • Merits/Demerits • Conclusion
  3. WEB 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 World Wide Web SOURCE :
  4. What is WEB ACCESSIBILITY? • Web Accessibility is about Universality, its about development of information systems flexible enough to accommodate the needs of maximum no. of users as possible :  with different environments  Different devices  To elderly people  Non-English Speakers  Impaired abilities • Web accessibility specifically means that people with disabilities can use the Web. • It means that people with disabilities can perceive, understand, navigate, and interact with the Web. SOURCE :
  5. Why WEB ACCESSIBILITY ? • Equal Accessibility=Equal Opportunity. • The UN Convention on the Rights of Persons with Disabilities recognizes access to information and communications technologies, including the Web, as a BASIC HUMAN RIGHT. • Accessibility supports social inclusion. • There is also a strong business case for accessibility. • It’s a LAW.
  6. It’s a LAW COUNTRY STANDARD LEGISLATION INDIA Guidelines for Indian Government Websites (based on WCAG 2 A) USA Section 508 (subset of WCAG 1 with a few additions) Section 508 of Rehabilitation Act FRANCE RGAA 3 (based on WCAG 2) Law No 2005-102, Article 47 CANADA WCAG 2 AA Human Rights Act 1977 GERMANY BITV 2 (based on WCAG 2) Federal Disabled Equalization Law (BGG) IRELAND WCAG 2 AA The Disability Act 2005 NEW ZEALAND WCAG 2 AA Human Rights Amendment Act 2001 UNITED KINGDOM WCAG 2 AA Equality Act 2010
  7. DISABILITY STATISTICS  Currently around 10 per cent of the total world's population, or roughly 650 million people, live with a disability.[1]  According to the new figures released by the Census Bureau in America[2]  19.9 million (8.2%) have difficulty lifting or grasping.  15.2 million (6.3%) have a cognitive, mental, or emotional impairment.  8.1 million (3.3%) have a vision impairment.  7.6 million (3.1%) have a hearing impairment.
  8. Types of Disabilities • There are 5 types of disabilities that can affect the way people use and interact with websites:-  Visual Disability  Auditory Disability  Mobility/Motor Disability  Photosensitive epilepsy  Cognitive Disability
  9. Visual Barriers(Blindness, color blindness, presbyopia) includes.. • Images(still or animated) • Video and visual elements • Inconsistent navigation or content • Lack of adequate color contrast • Certain color combinations • Small Headings • Text embedded in images
  10. Web Accessibility for Visually impaired Assistive technologies such as “braille displays”, “Screen Readers”. Display zoom capability Descriptive ALT texts for informative images Braille Displays SOURCE :
  11. SCREEN READERS SOURCE : screen-reader.jpg
  12. Sound Barriers(deafness, hard to hearing) can include: • Video or audio • Lack of transcript or captioning • Auditory stimulus that does not provide an alternative • Closed Captioning
  13. Web accessibility for auditory impaired •Transcript (or full text) for audio content •Captioning(or subtitle) for video content •Avoid flashing or flickering content •SOURCE : https://encrypted- UTTa78G9ayBJa9JsVGaIU9tpiTIezF-vq1yXQPRbJaoggnHg VIDEO CAPTIONING
  14. Motor Disability includes.. • Inability to use a mouse • Slow response time • Limited motor control • Assistive Technologies • Mouth stick • Head wand • Single-switch access • Sip and puff switch • Oversized trackball mouse • Adaptive keyboard • Eye tracking • Voice recognition software • Other assistive technologies
  15. For motor disability.. Challenges Solutions Users may not be able to use the mouse. Make sure that all functions are available from the keyboard (try tabbing from link to link). Users may not be able to control the mouse or the keyboard well. Make sure that your pages are error- tolerant (e.g. ask "are you sure you want to delete this file?"), do not create small links or moving links. Users may be using voice-activated software. Make sure that all functions are available from the keyboard. Users may become fatigued when using "puff-and-sip" or similar adaptive technologies. Provide a method for skipping over long lists of links or other lengthy content.
  16. Photosensitive epilepsy • Seizures can be caused by strobing, flickering, or flashing effects. • Present in different Science-fiction style Flash objects, horror movie previews etc. • In general, if the content flashes more than three times per second, is notably large, has bright contrast in the flashes, it may cause a seizure and should be avoided. • Of note is that SECTION 508 of WCAG prohibits flickering effects with a frequency greater than 2 Hz (flickers per second). 1qg7p8h.gif
  17. Cognitive disability includes.. • Difficulty in navigations • Complicated System to memorize and use • Ineffective Error Recovery • System is presented with inappropriate graphics, missing alternative texts, lengthy and complex content
  18. Word prediction aids Reading/Writing comprehension aids •Clear information chunks •Clear and specific labels •Avoid unnecessary motion •Avoid unnecessary time limit •Avoid flashing to prevent EPILEPSY •Avoid change of context automatically, without using trigger. For Cognitive Disability
  19. WCAG 2.0 • The World Wide Web Consortium(W3C) is committed to promoting usability for people with disabilities. • Follow WCAG 2.O • Guidelines for :  Aiding Disabled Audience  Aiding Agent type support • Universal access for everyone. • Broad and testable success criteria • Three levels: A, AA, AAA
  20. ACCESSIBILITY PRINCIPLES P O U R 638.jpg?cb=1437234388
  21. Guidelines • Provide equivalent alternatives to auditory and visual content. • Don’t rely on color alone. • Use markup and style sheets and do so properly. • Clarify natural language usage. • Create tables that transform gracefully. • Ensure that pages featuring new technologies transform gracefully. • Ensure user control of time sensitive content changes. • Provide context and orientation information. • Provide clear navigation mechanisms. • Ensure that documents are clear and simple.
  22. Essential Components for Web Accessibility These components include: Content Web browsers, media players assistive technology users' knowledge and experiences developers authoring tools evaluation tools
  23. Interdependencies Between Components • Technical specifications • WAI guidelines • Developers • Authoring tools • Evaluation tools • User agents • Assistive technologies • Users
  24. When accessibility features are effectively implemented in one component, the other components are more likely to implement them. The Implementation Cycle
  25. ACCESSIBILITY CHECKER 1. AChecker – Accessibility Checker Accessibility Checker is an open source accessibility evaluation tool that was developed in 2009 by the Inclusive Design Research Centre (formerly known as the Adaptive Technology Resource Centre) of the University of Toronto. Using this tool, the user can submit a web page via its URL or by uploading its HTML file and can subsequently select which guidelines to evaluate it against, namely the HTML Validator, WCAG 1.0 and WCAG 2.0.
  26. 2. WAVE – Web Accessibility Versatile Evaluator WAVE is a tool developed by WebAIM that is available both online and as a Firefox add-on. It reports accessibility violations by annotating a copy of the page that was evaluated and at the same time, providing recommendations on how to repair them. Rather than providing a complex technical report, WAVE shows the original Web page with embedded icons and indicators that reveal the accessibility information within your page.
  27. Benefits • Commercial: Accessibility increases the website use and it is cost effective. • Technical: produces a high quality and highly flexible website. • Legal: conformances with government requirements. • Ethical: Accessibility contributes to build a better society.
  28. Limitations • CAPTCHA: Difficulty in Considering All Types of Disabilities • People who cannot move any of their body parts • Assistive Technologies for Mobile Applications
  29. CONCLUSION • Check for Accessibility barriers for all major disability groups- Visual, Hearing, Physical, Cognitive • Select the testing technique or a combination of techniques • Once the scope of testing is defined, clearly identify the core pages and functionalities and verify each against manual Accessibility checklist. • Consider accessibility throughout the design and development process for seamless and elegant integration into web projects and to save development costs.
  30. References [1] [2] [3] accessibility-standards/ [4] [5] [6][7] [7] [8]