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 GUIDELINESProvide 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 CHALLENGEIn 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