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The legal specifics of web accessibility might vary a bit depending on what country you live in, but in terms of measuring your work against an internationally recognized standard, the guidelines you’ll refer to most are the WCAG, or Web Content Accessibility Guidelines. WCAG is broken up into four principles–you can use the acronym POUR to remember them. Accessible web content must be perceivable, operable, understandable, and robust.
In 2016,
a blind man named Guillermo Robles
0:00
sued Domino's Pizza after he was
unable to use a screen reader
0:06
to place an order through either
Domino's website or mobile app.
0:10
A lower court ruled against Domino's for
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violating the Americans
with Disabilities Act.
0:19
And disability advocates won
an important victory in 2019 when
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the United States Supreme Court
let the ruling stand.
0:26
But Domino's Pizza isn't the first
to be subject to a lawsuit due to
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online content that wasn't accessible
to users with disabilities.
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There's also Beyoncé.com, Amazon,
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Nike, Target, Netflix and Hulu,
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Harvard University, Fox News,
Burger King, CVS Pharmacy,
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Winn Dixie Supermarkets, Rolex watches,
Blue Apron...the list goes on and on.
0:59
And accessibility laws don't
just affect websites, and apps.
1:07
A company called Redbox was successfully
sued in 2014 because its DVD rental
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and return kiosks were not
accessible to blind users.
1:18
The legal specifics of web accessibility
1:23
might vary a bit depending
on what country you live in.
1:26
But in terms of measuring your
work against an internationally
1:30
recognized standard, the guidelines
you'll refer to most are the WCAG or
1:35
Web Content Accessibility Guidelines.
1:40
WCAG is broken
up into four principles.
1:44
You can use the acronym
POUR to remember them.
1:48
Accessible web content must
be perceivable,
1:52
operable, understandable,
and robust.
1:57
Within these four principles
are 13 accessibility guidelines.
2:02
This includes new success criteria added
version 2.1 of the WCAG documentation
2:08
in June 2018, relating primarily
to mobile accessibility.
2:15
The official WCAG
documentation is pretty dense.
2:23
Though fortunately there's plenty
of supplementary resources online
2:27
to help us understand the guidelines.
2:32
For example,
I've included in the teacher's notes
2:35
a resource called 13
Days of Accessibility,
2:39
which introduces each guideline in
a simpler, more visual fashion.
2:43
Each WCAG success criteria listing
is marked as level A, level AA,
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or level AAA, which describes
how difficult designers and
2:58
developers should expect compliance to be.
3:02
On the modern web, level A compliance
such as making sure color isn't the only
3:08
visual means of conveying information
should be easily within reach.
3:13
Level AA requires more effort, but
3:20
this should be the minimum accessibility
standard for online content.
3:23
Level AA color contrast compliance,
for example,
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means a text to background
color contrast ratio of
3:34
at least 4.5 to 1 for
text sizes below 18 points.
3:40
I'm using a resource called
the WebAIM Color Contrast Checker to
3:46
illustrate the difference.
3:50
On a pure white background, a medium blue
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such as #0077CC will meet the AA standard,
3:57
but it takes a significantly
darker blue to achieve
4:02
the 7 to 1 AAA contrast ratio.
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Note that for
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larger text such as a heading,
the contrast ratio is less restrictive.
4:13
3 to 1 to meet the AA standard, and
4:18
4.5 to 1 to meet the AAA standard.
4:21
Level AAA is described as the gold
standard level of accessibility.
4:26
Meeting AAA guidelines will create the
best possible experience for all users.
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However, some AAA criteria like providing
sign language interpretation for
4:38
all prerecorded audio content
require specialized and
4:45
sometimes expensive resources.
4:49
The WCAG documentation actually
doesn't mandate level AAA compliance
4:53
because it is not always possible to
satisfy all level AAA success criteria.
4:59
My recommendation? Treat level AA WCAG
compliance as an absolute must have.
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If your product doesn't meet this level of
accessibility, your work is unfinished.
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As for level AAA,
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apply these standards whenever it's
within your means and abilities to do so.
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In our upcoming videos
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we'll take a closer look at the four
WCAG principles of accessibility,
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starting with the letter P, perceivable.
5:37
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