Introduction To Web Accessibility

Introduction to web accessibility
Steven M. Swafford
Radical Development

Why Web Accessibility?
It’s The Law
Americans with Disabilities Act, 1996
Rehabilitation Act, 1998
It’s the RIGHT thing to do.
Not easy; not free

Goals of Web Accessibility
Improve the usability of technology for all technology users through Universal Design as an underlying approach.
Address accessibility challenges consistently over time.
Foster collaboration.

Accessible Technology For All
The goal is universal design that is integrated and equal: Don’t make disabled people use a different Web structure but make it so they can use it too.
Dan Fruchterman, Engineer’s Focus: Accessible Technology for All

Web Accessibility Overview
Web Accessibility Refers To The Inclusive Practice Of Making Websites Usable For People Of All Abilities And Disabilities
Well Designed And Developed Sites Provide All Users Access To Information And Functionality
The Assistive Needs That Web Accessibility Attempts To Address Include:
Visual
Motor/Mobility
Auditory
Seizures
Cognitive/Intellectual

The Web Accessibility Initiative (WAI)
Web Accessibility Initiative
Guidelines for:
Aiding disabled audience
Aiding agent-type support
The World Wide Web Consortium (W3C) is committed to promoting usability for people with disabilities
Universal access for everyone.
Must take into account user agents other than browsers: mobile phones, PDAs, screen readers and magnifiers, etc.

W3C Accessibility 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

Accessibility Principles
“Perceivable”
Alternative text and “text only” website equivalents
Supports assistive technologies (JAWS)
Text and audio transcripts for video and audio features
Remove reliance on shape, size, location, color, or sound to navigate
“Operable”
Use of keyboard alternative for site navigation
No action “timeouts”
Eliminate automatic “redirects” and other content changes
Eliminate blinking screen features at certain rates (seizures)
Alternative ways of finding other site pages (Table of Contents, Site Map)

Accessibility Principles, cont’d
“Understandable”
Identification of multi-lingual sections
Glossaries for acronyms and unusual terms
Identified page focus points as they change (for assistive technologies)
Consistent functionality presented consistently across pages
Intuitive and clear definition of input requirements and error messages
“Robust”
Supports plug ins, scripts, applets and other current and future user agents
Accessibility of PDFs and other file types to assistive technologies

Important Facts
15,000,000
Number of visually impaired people in the United States
28,000,000
Number people in the United States with some amount of hearing loss
September 6, 2006
A federal district court judge rules that a retailer may be sued if its website is inaccessible to the blind. (NFB v. Target)

Visual Barriers can include
Images (still or animated)
Video & Visual elements
“Downloadable” files w/plugins
Inconsistent navigation or content
Lack of adequate Color Contrast
Certain color combinations

Sound Barriers can include
Video or audio
Lack of transcript or captioning w/narrative
“Downloadable” files
Auditory stimulus that does not provide an alternative

the Challenge
In the United States, over 8 million people are blind or visually impaired
There were over 20 million deaf and hard of hearing people in the United States in 1994; of these about a million cannot understand any speech
Over a quarter of a million Americans have spinal cord injuries
About half a million Americans have cerebral palsy
A third of a million Americans have multiple sclerosis

Investigating within
How many people are expected to make use of the technology?
Is it likely to be used again in the future, or repeatedly?
Is it available publicly, or only to a pre‐determined audience?
Is it required to be used for academic or institutional purposes?

Checklist for building your site
Manual checking: how does site work with:
Images turned off
Sound turned off
Larger than normal font sizes
Small screen resolution
Black and white display
Without a mouse

Validating your sites
Check with a semi-automatic accessibility checker:
Wave
Bobby
Syntax check HTML through W3C validators
Do user testing

The effect of age
Physical impairments, minor and major, become more common with the passing years
More than half of the population in the United States over the age of 65 has some kind of impairment
This is a rapidly growing group; in the year 2000, there were 34.8 million people over 65, a number projected to be 53.7 million by 2020

What is a Screen reader?
Narrates (reads aloud) the text on the screen
Important considerations:
HTML tables must not be used to control layout: doing so makes the narration difficult to understand
HTML tables used to display tabular material need additional markup to make the meaning clear

Closed captioning
Common web accessibility guidelines indicate that captions should be:
Synchronized- the text content should appear at approximately the same time that audio would be available
Equivalent- content provided in captions should be equivalent to that of the spoken word
Accessible- caption content should be readily accessible and available to those who need

Closed captioning example

Accessibility In A Nutshell
An Accessible Website Is One That Can Be Used By Disabled People As Easily As By The Non-disabled.
Web Accessibility Means That People With Disabilities Can Perceive, Understand, Navigate, And Interact With The Web

Get Plugged In
Keep An Eyes On The WC3 Web Accessibility Initiative (WAI)
Review The Americans With Disabilities Act (ADA) Section 508

Additional Resources
WC3 Web Accessibility Initiative (WAI)
Americans With Disabilities Act (ADA) Section 508
How To Meet WCAG 2.0
WebAIM Screen Reader Simulation
Guidelines for Accessible, Usable Web Sites With Screen Readers
Voluntary Product Accessibility Template
WC3 Complete List of Web Accessibility Evaluation Tools
Section 508: Opening Doors To IT

Conclusion

Introduction To Web Accessibility

by Steven Swafford on Dec 18, 2010

Accessibility

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