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Unfortunately web content accessibility is being increasingly viewed solely from the perspective of how well a site complies with WCAG 2 rather than how well people with disabilities can access the content. During this session, I outline a new Accessibility Priority Tool (APT) that was developed in early 2013. This tool will help organizations and developers identify likely access barriers to web content, and prioritise their efforts to correct them.
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Accessibility: More than WCAG compliance
CSUN 2013
Accessibility:More than WCAG Compliance
CSUN: 27 February 2013San Diego
Roger HudsonWeb Usability
www.usability.com.au
Accessibility: More than WCAG compliance
CSUN 2013
tale of two sitesIt’s the best of times,
it’s the worst of times.
We have everything before us,
we have nothing before us.
(Apologies Charles Dickens)
Accessibility: More than WCAG compliance
CSUN 2013
#1Few images with no ALT attributes.Success Criterion 1.1.1 (Level A)
#2Colour contrast for all text is 3.2:1.Success Criterion 1.4.3 (Level AA)
which for the chop?
Accessibility: More than WCAG compliance
CSUN 2013
And, what about site visitors? Screen reader users
Screen magnifier users
Those with impaired colour vision
Older people
Those who choose to turn off images
Accessibility: More than WCAG compliance
CSUN 2013
Accessibility is about users
Accessibility: More than WCAG compliance
CSUN 2013
But, the conversation is increasingly about complying with rules
“Australian governments at all levels have endorsed WCAG 2.0, and require all government websites (federal, state and territory) to meet the new guidelines at the minimum compliance level (Single A) by the end of 2012. In addition, the Australian Government requires all federal websites to meet the medium conformance level (Double A) by the end of2014.”
Web Accessibility National Transition Strategy (http://www.finance.gov.au/publications/wcag-2-implementation/index.html)
Accessibility: More than WCAG compliance
CSUN 2013
Client: “Does my site comply with this WCAG?”(whatever that is)
How many times have you heard this?
Accessibility: More than WCAG compliance
CSUN 2013
• WCAG 2.0 doesn’t prevent the use of any technology(although some regulators may dictate otherwise)
• WCAG 2.0 Techniques are advisory – that is they are intended to provide advice and not rules
• Not all the Techniques for each Success Criterion are relevant or need to be complied with
And, WCAG is often misunderstood
Accessibility: More than WCAG compliance
CSUN 2013
Determining AccessibilityIt’s not rocket science
But, nor is it a piece of cake
Accessibility: More than WCAG compliance
CSUN 2013
Checklist conformance review
OR
User testing
In the perfect world, use both
Determining Accessibility
Accessibility: More than WCAG compliance
CSUN 2013
Is this form accessible?
Accessibility: More than WCAG compliance
CSUN 2013
WCAG 2.0 Success Criteria
1.3.1 Info and Relationships: Information, structure, and relationships conveyed through presentation can be programmatically determined or are available in text. (Level A)
3.3.2 Labels or Instructions: Labels or instructions are provided when content requires user input. (Level A)
4.1.2 Name, Role, Value: For all user user-interface components, the name and role can be programmatically determined; states, properties, and values that can be set by the user can be programmatically set; ... (Level A)
Accessibility: More than WCAG compliance
CSUN 2013
H44: Using label elements to associate text labels with form controls (HTML)
H65: Using the title attribute to identify form controls when the label element cannot be used (HTML)
WCAG 2.0 Sufficient Techniques
Accessibility: More than WCAG compliance
CSUN 2013
H44: Using label elements to associate text labels with form controls (HTML)
H65: Using the title attribute to identify form controls when the label element cannot be used (HTML)
Advisory TechniqueARIA1: Using the aria-describedby property to provide a descriptive label for input controls (ARIA)
WCAG 2.0 Sufficient Techniques
Five form inputs(NVDA)
Accessibility: More than WCAG compliance
CSUN 2013
Manual inspection, made easier with tools:WAT Toolbar for I.E.
Firefox developer & accessibility toolsWebAIM - WAVE
Power Mapper - SortsiteDeque – FireEyes and WorldSpace
Total ValidatoraViewer
etc
Checklist conformance review
Accessibility: More than WCAG compliance
CSUN 2013
One explicitly associated label
Accessibility: More than WCAG compliance
CSUN 2013
One input title
<span class="label">Text three</span><input class="input" title="text three" name="third" type="text">
Accessibility: More than WCAG compliance
CSUN 2013
What about the other three?
<label><span class="label">Text two</span><input class="input" name="second" type="text"></label>
Accessibility: More than WCAG compliance
CSUN 2013
What about the other three?
<label><span class="label">Text two</span><input class="input" name="second" type="text"></label>
<span class="label">Text four</span><input class="input" id="fourthinput" name="fourth" type="text">
<label class="label" id="five">Text five</label> <input class="input" id="fifthinput" name="fifth" type="text" aria-describedby="five“>
Accessibility: More than WCAG compliance
CSUN 2013
Summary: Identification of inputsNVDA: All identified, apart from ‘Text four’WCAG compliance: Yes, No, Maybe
?
?
Accessibility: More than WCAG compliance
CSUN 2013
Time to move on from 1999The year of WCAG 1.0
Accessibility: More than WCAG compliance
CSUN 2013
Look for the barriers to access as well as compliance with rules
Accessibility Barriers
Help not fearAccess Barrier Score System (2011)
NB: The proposed Access Barrier Score (2011) or the Accessibility Priority Tool (2013) are not suggested alternatives to, or replacements for WCAG 2.0.
Accessibility: More than WCAG compliance
CSUN 2013
Access Barrier Scores System (2011)
Identify and prioritise 26 common accessibility barriers
Accessibility: More than WCAG compliance
CSUN 2013
Accessibility Priority Tool (APT) 2013
Changes:• Name of some columns have changed• New column introduced (Importance Ranking)• Number of Access Barriers increased
Accessibility: More than WCAG compliance
CSUN 2013
Two new Access Barrier categories
Accessibility: More than WCAG compliance
CSUN 2013
New APT Excel column: “Importance ranking” Change in focus from an aid for accessibility evaluators, to a tool to help organisations and regulator prioritize accessibility issues.
Allows those responsible for setting accessibility requirements to rank the importance of each of the access barriers.
Importance rankings are determined prior to the accessibility evaluation depending on the circumstances. For example: • Regulators may set overall prioritise for issues• Individual organisations may use the rankings to focus on
the issues that are particularly relevant to their audiences• Organisations may rank issues depending on their abilities
to address them in a timely way.
Accessibility: More than WCAG compliance
CSUN 2013
Using the Accessibility Priority Tool
Demonstration of APT Excel worksheetThe following 5 slides outline the points raised.
Accessibility Priority Tool Worksheet
Accessibility: More than WCAG compliance
CSUN 2013
Preparing the APT worksheet: Importance ranking (Excel column H) • Rankings should set in advance by people with knowledge
of the organisation and accessibility.
• Based on organisation requirements and capabilities.
• Reflect needs of the organisation clients and site audience.
• For each barrier enter a score in the range of:1 (not important) to 5 (very important).
• After Importance Rankings have been entered, column H will usually be hidden in the worksheets used to do evaluations.
Accessibility: More than WCAG compliance
CSUN 2013
Using APT: Incidence score (Excel column D) Incidence score is entered by the person evaluating the site based on how frequently a site component causes an access barrier.
Five point scoring system:
0 – There is no incidence or occurrence of an access barrier.
1 – Page component causes access problems up to 25% of the time.
2 – Page component causes access problems between 25% and 50% of the time.
3 – Page component causes access problems between 50% and 75% of the time.
4 – The page component causes access problems more than 75% of the time.
The score is not a raw measure of how often a problem occurs. It indicates the percentage of times that the use of particular site component will cause an access barrier.
Accessibility: More than WCAG compliance
CSUN 2013
Using APT: Severity score (column E) Person evaluating the site uses the Severity score to rate the likely impact they believe each barrier will have for someone with a disability.
Uses a five point scoring system:
1. Minor inconvenience: Not likely to prevent access to content, but could be a minor irritant.
2. Minor difficulty: Not likely to prevent access to content, but could affect the ability of some people to use a page.
3. Average difficulty: Could make it difficult for some people to access content and use a page.
4. Major problem: Could prevent some people from accessing or using page content.
5. Extreme problem: Will prevent access to sections of the site or the ability to perform required functions.
Allocation of the severity rating is subjective and can be influenced by the experiences and knowledge of accessibility evaluator.
Accessibility: More than WCAG compliance
CSUN 2013
Using APT: Access Barrier Advice (column F) The APT Excel formula calculates the Access Barrier Advice from the:• Incidence and Severity scores entered by the accessibility evaluator, and
• Importance Ranking values entered by the site regulator or owner in advance.
The Access Barrier Advice is presented as:NoneLowMediumHighVery HighCritical
NB: The Access Barrier Advice generated by the APT worksheet is just a suggestion and should not be solely relied upon.
It may not accurately reflect the significance of a serious or important issue when the incidence is low.
Accessibility: More than WCAG compliance
CSUN 2013
Using APT: Comments (Excel column G) The Accessibility Priority Tool will automatically indicate what accessibility issues have to be addressed and when.
But, is a tool to help site managers make these decisions.
The Comments section is an important part of the tool.
It allows the person evaluating the accessibility of a site to provide their subjective impressions of the likely impact of potential access barriers, and highlight those that they believe will be most important.
For example, one critical images without a text alternatives among many images that do have alt attributes.
Accessibility: More than WCAG compliance
CSUN 2013
Lessons learnt and issues to explore • Setting the Importance Rankings and using the worksheet will
require knowledge of accessibility.
• I don’t think it is possible to make an automated system that can reliably prioritize accessibility issues for remediation.
• Difficult to balance the needs of people with disabilities, with the desire to have a tool that is not too daunting or difficult.
• The APT is not an alternative to WCAG when it comes to evaluating the accessibility compliance of sites.
Just saying something is a problem can lead greater resistance to the concept of web accessibility.
In my experience, many site owners and developers want to know how serious a problem is, for not all accessibility failings are equal.
Accessibility: More than WCAG compliance
CSUN 2013
It’s free to use and change as you wishBut please tell me, if it’s useful and how it might be improved
Accessibility Priority Tool
Accessibility: More than WCAG compliance
CSUN 2013
Accessibility Priority Tool
Thank you and any commentsRoger Hudson, Web Usability
www.usability.com.au
APT Article: http://usability.com.au/2013/01/accessibility-priority-tool/
APT Excel file: http://usability.com.au/wp-content/uploads/2013/01/Accessibility_Priority_Tool-worksheet.docx.xlsx