Web AccessHow do customers get to

your online stuff?

How do people access web sites?

Human ↔ Browser ↔ Web Site

1) A browser transforms content into something usable by most users.

2) A browser also passes content into the operating system's Accessibility API

Assistive Technology draws from the browser and the Accessibility API

Human ↔ AT ↔ Browser ↔ Web Site

Assistive technology transforms the content delivered by the browser into a format usable by the current user.

...if that content meets accessibility guidelines.

Web Content Accessibility Guidelines

Four Principles of Accessibility (POUR):1) Perceivable2) Operable3) Understandable4) Robust

Perceivable

1) Using their available senses, a user can perceive your content.

2) Visual elements can be conveyed in text transformed into audio

3) Audio elements can be read as text4) Elements can be perceived by touch through

braille

Operable

1) Input and interaction does not depend on a specific device, method of activating a device, or require special coordination or timing to access.

2) If a user makes an error, they should have the ability to recover from that error.

Understandable

1) Navigation should be consistent and logical2) Language should be simple and concise, as

appropriate for the audience.3) Alternative format and supplemental data should

be provided whenever possible.

Robust

All technologies employed in creating the application should be used according to their specifications, to ensure the best long-term interoperability with past, present, and future technologies.

Types of Assistive Technology

1) Screen Readers2) Screen Magnifiers3) Voice Commands4) Keyboard navigation5) Switch navigation

Screen Readers

1) Transform text content into audio2) Transform semantic information about operation

and relationships into audio3) Heavily use accessibility APIs4) Limitations: cannot directly access visual sources

like video or images.5) Solutions: alternative text and audio description

Screen Magnifiers

1) Enlarge view for low vision users2) Basic magnification available from browser or OS3) Almost entirely visual, though some have audio

readers.4) Limitations: narrow field of vision makes reading

and navigation challenging5) Solutions: mobile-friendly web sites where you

can switch into a single-column view

Voice Command

1) Alternative input methods for navigation and forms

2) Most products designed for executive dictation, not AT

3) Poor support for accessibility APIs4) Limitations: if the name for a control doesn't

match what is visible, voice commands won't work on that control.

5) Solutions: ensure that the label for a button or link matches what is seen visually.

Keyboard Navigation

1) Rare for a user to have no means to use a pointing device

2) Many types of AT primarily use the keyboard3) Circumstances can temporarily deny use of a

pointing device4) Two major issues:

a) Ability to reach and activate all content and controls

b) Ability to identify the current location on the page

Switch Navigation

1) Family of devices with very simple input mechanisms.

2) Same general limitations as keyboard navigation3) Switches can act like pointing devices in some

implementations.

What about the Deaf and Hard of hearing?

Deaf and Hard of Hearing

1) Audio Transcripts2) Video captioning and transcription3) English may not be primary language

Understanding Web Accessibility

Use the four principles of WCAG 2.0 to look at any content and consider whether it meets expectations for accessibility.

Contact Me

Joe Dolsonhttps://www.joedolson.comjoe@joedolson.com