When learning about accessible web best practices, you may have come across the POUR acronym which comes from four principles outlined by the W3C Web Content Accessibility Guidelines (WCAG).
The Web Content Accessibility Guidelines are internationally agreed up standards established to help content authors and developers create web content, whether a website, web application, or other digital technology, with accessibility in mind. The four principals of website accessibility that make up the POUR acronym are:
- perceivable,
- operable,
- understandable, and
- robust.
Continue reading for a more in-depth look at what each of these principles means.
Perceivable
The first letter in the POUR acronym stands for perceivable. For information and interface components to be perceivable, they need to be presentable to a user in a way that they can discern regardless of which senses they do or do not have use of.
This graphic shows the typical ways that we can perceive and interact with information on a website: via sight, sound, or, in some cases, touch.
For information on a website to be perceivable, it has to be capable of transforming from one form to another. The main content of the message has to be separate from how it is styled so that it can be perceived by users who may have no or limited use of one or more of their senses. For example:
- Videos must have captions for deaf or hard of hearing users.
- Audio files must have transcripts for deaf or hard of hearing users.
- Images must have aternative text describing the image for visually-impaired users.
- Text must be added to the page via HTML rather than CSS so that the text can still be read if styles are turned off completely.
Operable
The next letter in this acronym is O, which stands for operable. Simply put, this means that the user interface and navigation components of your website need to be able to be used by everyone, including people who do not navigate the web using a standard keyboard and mouse.
People with motor disabilities, quadriplegia, blindness, or even extreme cases of arthritis cannot use a mouse to click through websites. In this case, they must still be able to fully operate the interface of your website, and your website cannot require interactions that these users would be unable to perform or complete.
Key features of operable websites include:
- Multiple ways to interact with the website.
- User control over time limits/timing.
- Clear instructions and error recovery options that can be controlled regardless of ability.
Understandable
The next letter, U, stands for the principle understandable. An understandable website is one in which both the information presented and the way the website functions is clear to all users.
This means that, regardless of ability, people must be able to understand not only the information in your web content, but also how to navigate the website to find the information they want, and how to use any tools or features built into the website. Understandable websites have:
- Appropriately targeted language and reading level (typically at 8th- or 9th-grade reading level if writing for the general public).
- Supplemental representation of information, such as:
- summaries or excerpts before long articles.
- written descriptions of information contained in charts or graphs.
- transcripts of audio or video files.
- audio files allowing people to listen to pages instead of reading them.
- Understandable functionality which typically comes from elements like
- consistent font styles (family, colors, and sizing) across all pages of the site.
- a well-thought-out and easy to use navigation structure.
- clear instructions for forms and visible form labels.
- tooltips or “getting started” guides for special features.
Robust
The last letter in the POUR acronym stands for robust. Your website needs to be robust enough that it supports and can be accessed on a variety devices, including assistive technologies. This means that as technology and user agents evolve, the content must still remain accessible, and be able to be interpreted.
Ideally, robust websites must:
- be functional across current and (as much as possible) future devices, operating systems, and browsers.
- support some outdated operating system and browser versions, as elderly people and people who use assistive technology are less likely to always be running the most up-to-date versions of their browser or operating system.
- validate against technical standards for any applicable platforms.
Incorporating POUR into Your Website
With each of these principles comes a set of guidelines and specific success criteria for meeting the website accessibility POUR principles. In order to make sure your website is POUR: perceivable, operable, understandable, and robust, you will need to take each guideline and success criterion into consideration.
For more on the principles, guidelines, and success criteria of the WCAG, read “Understanding the Four Principles of Accessibility” on the W3 website.
If you want to make sure your web content follows the principles of accessibility but you aren’t sure where to start, contact us. Our team of trained accessibility consultants can help you to navigate relevant guidelines and create a website that’s accessible now and for years to come.
