2. What is Web Accessibility?
Myth
Accessibility is often viewed as
making your site work on screen readers.
What Accessibility really is
Accessibility is a subset of UX
focused on making your websites usable
by the widest range of people possible,
including those who have disabilities.
3. Why should we care about Accessibility?
The main reason is the concept’s definition itself:
we want our application to be usable by as many people as possible.
We should also care due to good ethics and laws and regulations.
4. Statistics:
Persons with disabilities in Europe are a significant group:
● 10% to 15% of the total population
● 50 to 75 million people in EU27*
● There is a strong correlation between disability and ageing (numbers increase with
demographic change)
Source: Labour Force Survey (European Commission-Eurostat 2002)
http://ec.europa.eu/ipg/standards/accessibility/index_en.htm
*EU27 - European Union during 2007 - 2013 when it had 27 countries
- European Union after 2016 without UK due to Brexit
5. Disabilities to
account for:
1. Blindness and vision impairment
2. Deaf and hard of hearing
3. Physical disabilities
4. Cognitive disabilities
6. 1. Blindness and Vision impairment
● Total blindness
● Legally blind
● Color blindness
7. 1. Blindness and Vision impairment
A person is legally blind if:
- his/her visual acuity is less than 20/200
At the distance of 20 feet (~6m), a person doesn’t see a text,
which can be seen at 200 feet (~60m) by a person with perfect eyesight.
- his/her view angle is less than 20 degrees
https://www.allaboutvision.com/lowvision/legally-blind.htm
12. 1. Blindness and Vision impairment
Color blindness is a deficiency in distinguishing colors.
The ideal contrast ratio between two colors is of 4.5:1
https://webaim.org/resources/contrastchecker/
Chrome extension for live color blindness simulation:
https://chrome.google.com/webstore/detail/i-want-to-see-like-the-co/jebeedfnielkcjlcokhiobodkjjpbjia
Side by side color blind comparison tool:
https://www.toptal.com/designers/colorfilter
13. 1. Blindness and Vision impairment
Accessibility solutions and tools:
● Braille
● Screen readers
● Screen magnifiers
● Scaling the UI (entirely)
● Font size increase (only)
● High contrast Themes
Humanware Braillant BI 40
Freedom Scientific JAWS
14. Disabilities to
account for:
1. Blindness and vision impairment
2. Deaf and hard of hearing
3. Physical disabilities
4. Cognitive disabilities
15. 2. Deaf and hard of hearing
People with a hearing disability rely heavily on visual information.
We should provide audio and video content
with a description and subtitles (closed captions).
Do not autoplay media content.
An interview with a Deaf academic librarian on web experience:
https://developer.paciellogroup.com/blog/2017/02/sounding-out-the-web-accessibility-for-deaf-and-hard-of-hearing-people-part-1/
https://developer.paciellogroup.com/blog/2017/03/sounding-out-the-web-accessibility-for-deaf-and-hard-of-hearing-people-part-2/
16. Disabilities to
account for:
1. Blindness and vision impairment
2. Deaf and hard of hearing
3. Physical disabilities
4. Cognitive disabilities
17. 3. Physical disabilities
For physical disabilities, we need to take into account
users that don’t navigate web pages with
the traditional mouse (along a keyboard).
Ensuring the possibility to navigate by keyboard exclusively
should be good enough for the time being, but have in mind
other means such as Eye Controlling.
https://www.tobii.com/tech/
https://arstechnica.com/gadgets/2017/08/windows-adding-eye-control-to-boost-accessibility/
18. Disabilities to
account for:
1. Blindness and vision impairment
2. Deaf and hard of hearing
3. Physical disabilities
4. Cognitive disabilities
20. 4. Cognitive disabilities
In regards to dyslexia, sans-serif fonts are recommended
and fonts that have an unique shape for each letter.
e.g.: Arial, Comic Sans*, Verdana, Century Gothic
A font created with dyslexia in mind:
https://www.dyslexiefont.com/en/typeface/
*Comic Sans is a great font choice for countering dyslexia
21. 4. Cognitive disabilities
Not all disabilities can be overcome purely from the UI.
We need to understand the difficulties our users are facing and only then,
together with the UX, we can probably do something about it.
Dark Patterns: tricks used in websites and apps
that make you buy or sign up for things you didn’t mean to.
Darkpatterns.org
About users with social disorders using the web:
https://developer.paciellogroup.com/blog/2018/08/a-web-of-anxiety-accessibility-for-people-with-anxiety-and-panic-disorders-part-1/
22. Disabilities to
account for:
1. Blindness and vision impairment
2. Deaf and hard of hearing
3. Physical disabilities
4. Cognitive disabilities
23. Laws and Regulations
Starting with January 2010, all new EUROPA websites
must be compliant with the Web Content Accessibility Guidelines 2.0, level AA.
http://ec.europa.eu/ipg/standards/accessibility/index_en.htm
In 2017, WCAG 2.0 AA compliance has been imposed in the U.S. as well.
https://siteimprove.com/en-us/blog/no-more-excuses-there-is-now-a-us-deadline-for-beco
ming-accessible/
WCAG 2.0 standard:
https://www.w3.org/TR/WCAG20/
24. Laws and Regulations
Here’s a glimpse of WCAG 2.0 AA rules:
● Links
Links must have a context.
The text within the link must be discernible.
● Media
Captions are provided for all live audio content in synchronized media.
● etc
26. Semantic Markup
Each HTML tag has been created with a purpose.
Developers have enough flexibility to use every tag as any tag,
filling the behavior with CSS and JS.
By using the markup as intended, it gives the document meaning (or semantics).
35. WAI-ARIA
Web Accessibility Initiative - Accessible Rich Internet Applications
It is a technical specification created by the World Web Consortium (W3C)
on increasing accessibility of the web.
https://w3c.github.io/aria/
With HTML, CSS and JS we can recreate the behaviour of any existing tag.
With WAI-ARIA, we can fill the accessibility gaps.
36. WAI-ARIA
Roles: defines what an element is or does
e.g.: role=”navigation”
The HTML5 tag <nav> is a Landmark with the ARIA role of navigation built-in.
We can manually add the ARIA landmark role=”navigation” to any html tag.
Properties: used for adding extra meaning or semantics to elements
e.g.: aria-required=”true”
States: special properties that define the current condition of elements
e.g.: aria-disabled=”true”
37. WAI-ARIA
Start building an UI with native HTML elements
(they have built in semantics and behavior).
Continue with adding ARIA roles, states and properties
to the elements lacking the desired accessibility.
List of all ARIA landmark roles:
https://www.w3.org/TR/wai-aria-practices/examples/landmarks/HTML5.html
41. Tools: Accessibility DOM Tree
We can think of the Accessibility Tree as an API describing
the basic page structure with less information and fewer nodes.
e.g.: example of an Accessibility DOM Tree for a basic form
45. Screen Readers
A screen reader is a form of assistive technology.
It facilitates user interaction with content.
It relies on a user agent to retrieve and render content.
47. Screen Readers
Screen Readers react to ALL CAPS and CSS text-transform: uppercase.
There are two specs that we can use to customize the way the screen reader reads:
1. CSS Speech Module (limited browser support)
https://www.w3.org/TR/2018/NOTE-css3-speech-20180605/
The Speech Module is the successor of Aural Style Sheets (deprecated).
https://developer.mozilla.org/en-US/docs/Web/CSS/Aural
2. Web Speech API
This specification defined a JavaScript API that enables integrating speech recognition
and synthesis into web pages.
https://w3c.github.io/speech-api/speechapi.html
48. Screen Readers
Both CSS Speech Module and Web Speech API use Text To Speech (TTS).
A Text To Speech system converts normal language text into speech.
TTS engines are built in most platforms.
Voice assistants like Alexa or Google Assistant use the platform’s TTS most of the times.
But they can also use a bundled TTS alternative (for better language support or a wider
choice of voices).
https://tink.uk/using-the-web-speech-api-to-simulate-css-speech-support/
50. The A11Y Project
The A11Y project’s main goal is to facilitate accessibility implementation on the web.
It is an open-source initiative, with the objective of promoting accessibility.
It provides an up-to-date collection of resources and how-to examples and it also tracks
events on the topic.
The term ‘A11Y’ stands for AccessibilitY as a numeronym.
11
https://a11yproject.com/