Disabilities and Accessible Web Wladyslaw Bultrowicz Wladyslaw Bultrowicz wladyslaw.bultrowicz @deri.org SemInf, 21 .03.2007

Presentation outline Introduction Motivation Possible classification of disabilities Couple “ dos & don’ts” Assistive Technologies & Adaptive Strategies

Introduction

Motivation

Possible classification of disabilities

Couple “ dos & don’ts”

Assistive Technologies & Adaptive Strategies

Introduction There are many disabilities that can affect access to Web Abilities can vary from person to person, and over time . People can have combinations of different disabilities, and combinations of varying levels of severity. There are (as yet no universally accepted) categorizations of disability, despite efforts towards that goal.

There are many disabilities that can affect access to Web

Abilities can vary from person to person, and over time .

People can have combinations of different disabilities, and combinations of varying levels of severity.

There are (as yet no universally accepted) categorizations of disability, despite efforts towards that goal.

Motivation Current Web is not really easy to use for people with disabilities. Web has increasingly important role in society. Access to the Web is vital. Equal opportunities! Improvements designed for disabled can benefit Web users who do not have disabilities.

Current Web is not really easy to use for people with disabilities.

Web has increasingly important role in society. Access to the Web is vital. Equal opportunities!

Improvements designed for disabled can benefit Web users who do not have disabilities.

Classification V isual disabilities (blindness, low vision, color blindness) Avoid (blindness): images that do not have alternative text complex images (e.g., graphs or charts) that are not adequately described forms that cannot be tabbed through in a logical sequence or that are poorly labeled browsers and authoring tools that lack keyboard support for all commands non-standard document formats that may be difficult for screen reader to interpret

V isual disabilities (blindness, low vision, color blindness)

Avoid (blindness):

images that do not have alternative text

complex images (e.g., graphs or charts) that are not adequately described

forms that cannot be tabbed through in a logical sequence or that are poorly labeled

browsers and authoring tools that lack keyboard support for all commands

non-standard document formats that may be difficult for screen reader to interpret

Classification Avoid (low vision) Web pages with absolute font sizes that do not change easily Web pages that, because of inconsistent layout, are difficult to navigate when enlarged, due to loss of surrounding context Avoid (color blindness) color that is used as a unique marker to emphasize text text that inadequately contrasts with background color or patterns browsers that do not support user override of authors' style sheets

Avoid (low vision)

Web pages with absolute font sizes that do not change easily

Web pages that, because of inconsistent layout, are difficult to navigate when enlarged, due to loss of surrounding context

Avoid (color blindness)

color that is used as a unique marker to emphasize text

text that inadequately contrasts with background color or patterns

browsers that do not support user override of authors' style sheets

Classification H earing impairments ( deafness , hard of hearing ) Avoid lack of captions or transcripts of audio on the Web, including webcasts requirements for voice input on Web sites (Mich ae l walks through his high rise apartment to a large wall covered in newspaper clippings and starts tearing them down, revealing a large window. He puts the articles into a box. Then Micha e l takes the hard drive chip from his computer and walks out onto the balcony. Giving a sigh, he heaves it into the river.) CUT TO: [EXT. CHICAGO SAVINGS BANK-DAY] CUT TO: [INT.MAIN AREA OF THE BANK-DAY] Micha e l: (Fires three rounds into the air, then points the gun at the clerk) The vault. Open it. Clerk: We can ’ t. The branch manager ’ s not here. Micha e l: (Looks away and back at her.) Where is he?

H earing impairments ( deafness , hard of hearing )

Avoid

lack of captions or transcripts of audio on the Web, including webcasts

requirements for voice input on Web sites

Classification P hysical disabilities (motor disabilities, amputies ) Avoid: time-limited response options on Web pages browsers and authoring tools that do not support keyboard alternatives for mouse commands forms that cannot be tabbed through in a logical order S peech disabilities Avoid: Web sites that require voice-based interaction and have no alternative input mode

P hysical disabilities (motor disabilities, amputies )

Avoid:

time-limited response options on Web pages

browsers and authoring tools that do not support keyboard alternatives for mouse commands

forms that cannot be tabbed through in a logical order

S peech disabilities

Avoid:

Web sites that require voice-based interaction and have no alternative input mode

Classification C ognitive and neurological disabilities dyslexia and dyscalculia attention deficit disorder (ADD/ADHD) intellectual disabilities memory impairments mental health disabilities seizure disorders Avoid distracting (audio/video) elements that cannot easily be turned off use of visual or audio frequencies that can trigger seizures

C ognitive and neurological disabilities

dyslexia and dyscalculia

attention deficit disorder (ADD/ADHD)

intellectual disabilities

memory impairments

mental health disabilities

seizure disorders

Avoid

distracting (audio/video) elements that cannot easily be turned off

use of visual or audio frequencies that can trigger seizures

Assistive Technologies & Adaptive Strategies alternative keyboards or switches (small/big keys, key guards) braille machines screen magnifiers screen readers speech recognition /synthesis text browsers visual notification voice browsers tabbing through structural elements

alternative keyboards or switches (small/big keys, key guards)

braille machines

screen magnifiers

screen readers

speech recognition /synthesis

text browsers

visual notification

voice browsers

tabbing through structural elements

Remember! Make Semantic Web real … and accessible !!

Make Semantic Web real … and accessible !!