web accessibility - an introduction patrick h. lauke

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Date or reference Web Accessibility - an introduction Patrick H. Lauke ISI presentation - 15/12/2005

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Web Accessibility - an introduction Patrick H. Lauke. ISI presentation - 15/12/2005. Introduction. What we’ll cover today: some of the misconceptions about accessibility reasons why accessibility is important highlight some web accessibility guidelines - PowerPoint PPT Presentation

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Page 1: Web Accessibility - an introduction Patrick H. Lauke

Date or reference

Web Accessibility - an introductionPatrick H. Lauke

ISI presentation - 15/12/2005

Page 2: Web Accessibility - an introduction Patrick H. Lauke

15/12/2005 2

Introduction

What we’ll cover today:

• some of the misconceptions about accessibility

• reasons why accessibility is important

• highlight some web accessibility guidelines

Q&A at the end, but please shout out any questions.

Page 3: Web Accessibility - an introduction Patrick H. Lauke

15/12/2005 3

So why am I here?

• involved in web since early 90s

• University webmaster since 2001

• responsible for writing and enforcing web strategy, standards and guidelines for UoS

• involved in global discourse on accessibility

• WaSP (Web Standards Project) Accessibility Task Force

Page 4: Web Accessibility - an introduction Patrick H. Lauke

15/12/2005 4

Some misconceptions

What is accessibility?

“making sure our web site works for the blind…”

There is a wide range of disabilities:

• visual impairments

• auditory impairments

• mobility impairments

• cognitive disabilities

Page 5: Web Accessibility - an introduction Patrick H. Lauke

15/12/2005 5

Some misconceptions

Why bother?

Marketing executive:

“such a small market is not worth the hassle”

Web designer:

“no time to create a separate accessible site”

Site owner:

“blind people won’t be using my web site”

Page 6: Web Accessibility - an introduction Patrick H. Lauke

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Some misconceptions

Marketing executive:

“such a small market is not worth the hassle”

It is estimated that there are 7 million disabled people in the UK and that around 19% of the working age population has some form of disability.

Source: Disability Rights Commission – Disability briefing January 2004

Page 7: Web Accessibility - an introduction Patrick H. Lauke

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Some misconceptions

Web designer:

“no time to create a separate accessible site”

In majority of cases, no need for special “disabled only access” site.

• Inclusive design, not segregation

• Separation of content and presentation, using web standards, structural markup: single site, accessible to all

• Accessibility included in planning stage, not as an afterthought

• “Text only” is not a solution

Page 8: Web Accessibility - an introduction Patrick H. Lauke

15/12/2005 8

Some misconceptions

Site owner:

“blind people won’t be using my web site”

Accessibility not just about the blind, but…

A possible scenario: visually impaired customer buying photographs or paintings for a sighted relative?

Page 9: Web Accessibility - an introduction Patrick H. Lauke

15/12/2005 9

Legal requirements

If the ethical / moral and financial reasons were not enough, there are legal requirements:

• UK - Disability Discrimination Act 1995provision of goods and services

• Australia – Disability Discrimination Act 1992• USA – Americans with Disabilities Act• USA – Section 508 of Rehabilitation Act

procurement policy for federal government agencies

Other countries have similar legislation.

Cases are being brought to court: SOCOG, RNIB, Ramada/Priceline…

Page 10: Web Accessibility - an introduction Patrick H. Lauke

15/12/2005 10

Access for all

More importantly

• Accessibility is not just about users with disabilities

• Provisions and changes made for accessibility can benefit all users

“Real world” example: access ramps

With regards to web:

• Benefits to users of alternative browsing devices (PDAs, web phones, etc)• Not a permanent disability, but “situational” – library PC, loud environment, etc

Crossover between usability and accessibility

Page 11: Web Accessibility - an introduction Patrick H. Lauke

15/12/2005 11

Accessibility and SEO

Google and co.world’s largest “disabled users”

Page 12: Web Accessibility - an introduction Patrick H. Lauke

15/12/2005 12

W3C Guidelines

So…what’s a web designer to do?

World Wide Web Consortium (W3C) committed to 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

W3C Web Accessibility Initiative (WAI) produced Web Content Accessibility Guidelines (WCAG)

Page 13: Web Accessibility - an introduction Patrick H. Lauke

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W3C Guidelines

WCAG 1.0, 5 May 1999

14 guidelines (general principles), broken down into checkpoints.

Checkpoints categorised into 3 priority levels

• [Priority 1] A Web content developer must satisfy this checkpoint.

• [Priority 2] A Web content developer should satisfy this checkpoint.

• [Priority 3] A Web content developer may address this checkpoint.

Page 14: Web Accessibility - an introduction Patrick H. Lauke

15/12/2005 14

W3C Guidelines

1. Provide equivalent alternatives to auditory and visual content.2. Don't rely on color alone.3. Use markup and style sheets and do so properly.4. Clarify natural language usage5. Create tables that transform gracefully.6. Ensure that pages featuring new technologies transform gracefully.7. Ensure user control of time-sensitive content changes.8. Ensure direct accessibility of embedded user interfaces.9. Design for device-independence.10. Use interim solutions.11. Use W3C technologies and guidelines.12. Provide context and orientation information.13. Provide clear navigation mechanisms.14. Ensure that documents are clear and simple.

Not going to go through all, but give a few examples

Page 15: Web Accessibility - an introduction Patrick H. Lauke

15/12/2005 15

WCAG examples

1) Provide equivalent alternatives to auditory and visual content.

ALTernate text for images

Page 16: Web Accessibility - an introduction Patrick H. Lauke

15/12/2005 16

WCAG examples

1) Provide equivalent alternatives to auditory and visual content.

Captions and transcripts for audio/video files

http://www.splintered.co.uk/experiments/66/

Page 17: Web Accessibility - an introduction Patrick H. Lauke

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WCAG examples

2) Don’t rely on color alone

Coloured buttons without any additional information

Page 18: Web Accessibility - an introduction Patrick H. Lauke

15/12/2005 18

WCAG examples

2) Don’t rely on color alone

Coloured links surrounded by normal text

Page 19: Web Accessibility - an introduction Patrick H. Lauke

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WCAG examples

3) Use markup and style sheets and do so properly.

<p><font size=“+3”><b>This is a heading</b></font></p>

<p>Blah blah blah</p>

<p><font size=“+3”><b>This is another heading</b></font></p> <p>Blah blah blah</p>

<p><font size=“+2”><b>A sub-section</b></font></p> <p>Blah blah blah</p>

Page 20: Web Accessibility - an introduction Patrick H. Lauke

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WCAG examples

3) Use markup and style sheets and do so properly (cont.)

<h1>This is a heading</h1> <p>Blah blah blah</p><h1>This is another heading</h1> <p>Blah blah blah</p><h2>A sub-section</h2> <p>Blah blah blah</p>

• Machine-readable.• Convey meaning and structure, not just visual appearance.• Cfr MS Word and screen readers.• “But the headings look ugly…” – use CSS

Outline:

•This is a heading•This is another heading

–A sub-section

Page 21: Web Accessibility - an introduction Patrick H. Lauke

15/12/2005 21

WCAG examples

6) Ensure that pages featuring new technologies transform gracefully

• Plugin technologies: Java, Flash, Shockwave.

• Scripting: VBScript (IE only!), reliance on javascript.

Worst case: navigation or other essential page feature.

Page 22: Web Accessibility - an introduction Patrick H. Lauke

15/12/2005 22

WCAG examples

6) Ensure that pages featuring new technologies transform gracefully

Javascript popups – what happens when JS is off/unavailable?

<a href=“#” onclick=“window.open(‘foo.html’)”>bar</a>

Can be made accessible (fallback mechanism):

<a href=“foo.html” onclick=“window.open(this.href); return false;”>bar</a>

Page 23: Web Accessibility - an introduction Patrick H. Lauke

15/12/2005 23

WCAG examples

9) Design for device-independence

• Mouse• Keyboard• Voice activation• Switches• Headwands

Don’t rely on mouse, e.g. onmouseover/onmouseout javascript event handlers. Choose device-independent alternatives instead: onfocus/onblur

Page 24: Web Accessibility - an introduction Patrick H. Lauke

15/12/2005 24

WCAG examples

9) Design for device-independence

Ensure sensible tab order (links, form elements, etc)

Page 25: Web Accessibility - an introduction Patrick H. Lauke

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WCAG examples

…and many, many more.

Page 26: Web Accessibility - an introduction Patrick H. Lauke

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Automated validators

The infamous “Bobby”…(now WebXact http://webxact.watchfire.com/ )

• Automated accessibility checkers are dumb.

• “Bobby” and co. are just a tool and do not replace human checks.

• False positives, false negatives.See:http://www.isolani.co.uk/blog/access/SiteMorseFailsDueDiligence

All my images have an ALTernate text of “image”…is that accessible?

Page 27: Web Accessibility - an introduction Patrick H. Lauke

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Conclusion

Hopefully, what you’ll take away from this presentation:

• Accessiblity not just about “the blind”

• Moral, financial and legal reasons to ensure web sites are accessible

• Accessibility can benefit all users

• W3C WAI WCAG and some examples

Worth noting: accessibility not about rote mastery of a few guidelines. Many cases where there is no one single solution – requires judgement and compromise.

Page 28: Web Accessibility - an introduction Patrick H. Lauke

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Word of warning?

Want to do web design/development as a job?

Essential skills – not just an option:

• Web standards (semantic/structural markup, CSS)

• Accessibility (beyond “Bobby”)

Page 29: Web Accessibility - an introduction Patrick H. Lauke

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Resources

• W3C Web Accessibility Initiativehttp://www.w3.org/WAI/

• Accessifyhttp://www.accessify.com/

• Accessifyforumhttp://www.accessifyforum.com/

• WebAIM: Web Accessibility In Mindhttp://www.webaim.org/

• Isolanihttp://www.isolani.co.uk/

• Dive into Accessibilityhttp://www.diveintoaccessibility.org/

• “Evaluating Web Sites for Accessibility with the Firefox Web Developer Toolbar”http://www.webaim.org/techniques/articles/evaluatingwithfirefox

• WaSP (Web Standards Project)http://webstandards.org