FIT1050 Web Fundamentals
Web Content Accessibility
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Learning objectives
Understanding Accessibility Issues
¡ñ Understand broad concepts of accessibility
¡ñ Consider the impact of situational impairments Accessibility principles for the Web
¡ñ Differentiate between types of accessibility problems
¡ñ Legal requirements for web accessibility
¡ñ Web accessibility initiatives and guidelines
Web content accessibility techniques
¡ñ Simple and practical solutions for accessible content
Understanding Accessibility Issues
What is accessibility?
Wikipedia: Accessibility can be viewed as the “ability to access” and benefit from some system or entity. The concept focuses on enabling access for people with disabilities… however, research and development in accessibility brings benefits to everyone.
W3C: Accessibility is a simple thing, a philosophy, although in some countries it is also part of the law: Accessibility is treating everyone, no matter what their ability, the same…
Accessibility strives to provide people with equal access to content and services.
Accessibility does not mean that every user needs to have an identical experience.
Ask an expert…
At the launch of the W3C’s Web Accessibility Initiative (WAI):
“The power of the web is in its universality. Access by everyone regardless of disability is an essential aspect.”
– Sir Tim Berners-Lee, 1997
https://www.w3.org/Press/IPO-announce
Compared to “usability”
Similar approaches and goals, but not the same thing!
¡ñ Usability – the degree to which something is designed for a specific use.
¡ð Goal: efficiency, effectiveness and satisfaction for a defined group of users –
not necessarily all users.
¡ñ Accessibility – the degree to which a system is usable by as many people as possible without modification.
¡ð Goal: equality of access and removal of barriers to access based on personal, technical or environmental limitations – including disabilities.
Who is affected by disability?
Over 4.4 million people in Australia have a disability (2018)
¡ñ 18% of men and women
¡ñ 50% aged 65 and over have one or more disabilities
¡ñ 13% of working age (15-64) have a disability
For people with a disability:
¡ñ 77% have a physical health condition as their main disability
¡ñ 23% have a mental health condition as their main disability
Health conditions can be hereditary, or can be acquired from an illness or injury.
https://www.aihw.gov.au/reports/disability/people-with-disability-in-australia/contents/people-with-disability/prevalence-of-disability
Some types of disabilities and impairments
¡ñ Blindness
¡ñ Low vision
¡ñ Colour blindness
¡ñ Hearing loss
¡ñ Deafness
¡ñ Hypersensitivity
¡ñ Amputation
¡ñ Arthritis
¡ñ Muscular dystrophy ¡ñ Repetitive strain
¡ñ Tremors and spasms
¡ñ Dementia
¡ñ Dyslexia
¡ñ Attention Deficit
¡ñ Downs syndrome ¡ñ Autism
Technologies such as the World Wide Web can remove barriers to communication and interaction that many people face in the physical world.
Accessibility problems are design problems
¡°Disability is not just a health problem. It is a complex phenomenon, reflecting the interaction between features of a person¡¯s body and features of the society in which he or she lives.¡±
– World Health Organisation
Accessibility problems occur when designers create interactions that exceed the abilities of users.
Disability
Personal Health Condition
Disability
Mismatched Human Interactions
Other impairments and limitations
There are many reasons why people may be experiencing varying degrees of auditory, cognitive, physical, speech, and visual limitation.
By designing for someone with a permanent disability, someone with a temporary impairment or situational limitation can also benefit.
Accessibility Principles for the Web
The Web enables opportunities for access
browses the Web with assistive devices:
¡ñ Refreshable braille display
¡ñ Screen reader
Also note:
¡ñ Choice of device
¡ñ Keyboard input
Legal implications and obligations
The Australian government has endorsed the Web Content Accessibility Guidelines 2.0 for ALL government websites.
¡ñ https://info.australia.gov.au/accessibility.html
Australian Disability Discrimination Act 1992
¡ñ Information must be provided in an accessible manner
¡ñ Currently compliant to Level A working toward Double A (with some Triple A)
USA has Section 508 of the Workforce Rehabilitation Act
¡ñ Electronic and information technology that is developed or purchased by all Federal Agencies must be accessible by people with disabilities.
Australia was the first country to have its discrimination laws tested in this area: Maguire v SOCOG in 1999.
¡ñ Maguire asserted that significant parts of the Games website were inaccessible to him.
SOCOG¡¯s defense was that compliance would be an ¡°unjustifiable hardship¡±
¡ñ This is the only real defense allowed by the Disability Discrimination Act
¡ñ SOCOG estimated that 1 person working 8 hours days would require 368 days to
make the website accessible, at a total cost of $2.2 million
¡ñ Expert witnesses estimated that the work could be done in about 4 weeks at a
cost of around $30,000
Components of accessible design
https://www.w3.org/WAI/intro/components.php
W3C software accessibility guidelines
Accessibility goes beyond ensuring website content is accessible. Tools used to create and access websites must be compatible.
Authoring Tool Accessibility Guidelines (ATAG)
¡ñ Help developers create tools that promote production of accessible content.
¡ñ Make tools themselves accessible so that anyone can create content.
User-agent Accessibility Guidelines (UAAG)
¡ñ Explain how to make accessible software for people with disabilities.
¡ñ Ensure that web browsers work with assistive devices.
W3C and Web content design guidelines
Accessible Rich Internet Applications (WAI-ARIA)
¡ñ Attributes that can be added to HTML to identify interface element roles.
¡ñ Accessible reporting of DOM state and page updates via JavaScript APIs.
Web Content Accessibility Guidelines (WCAG) 2.1
¡ñ Principles that allow common accessibilities issues to be classified.
¡ñ Guidelines that set basic goals for developers to work towards
¡ñ Success criteria that are used to test conformance a various levels
¡ñ Techniques defining methods that can be used to meet success criteria
ARIA for dynamic elements
Dynamic scripted interactions require more work to ensure that changes occurring within a web page can be reported back to user-agents.
The Accessible Rich Internet Applications (ARIA) standard uses attributes set using HTML and JS to report the current and changed states of elements to the browser.