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This article details a point in the Web Content Accessibility Guidelines and what the implications are for creating accessible course content in Evolve and is part of a larger path.

To view the full guidelines, please visit the Accessibility: WCAG 2.1 and Evolve path.

Guideline 1.4.1

Use of Color Level A Color is not used as the only visual means of conveying information, indicating an action, prompting a response, or distinguishing a visual element.


This is a straightforward guideline: don’t use color to convey meaning. An example would be ‘Click on the red button if you think it should, and click on the green button if you think it shouldn’t.’

What does this mean for your content in Evolve?

This is easy to adhere to - make sure when you create content you aren’t relying on color as the sole means of identifying anything. You can still include color to signify different things, but don’t make it the only means of doing so. Make sure everything is adequately labeled so meaning and differentiation are clear with text.

Guideline 1.4.2

Audio Control Level A If any audio on a Web page plays automatically for more than 3 seconds, either a mechanism is available to pause or stop the audio, or a mechanism is av


Another straightforward guideline: anything that plays audio automatically must have volume control and the ability to pause.

What does this mean for your content in Evolve?

Any component that plays audio in Evolve (for example the Audio Component, the Media Component) has play and pause controls and independent volume controls (labeled for screen readers).

While the Media Component can be set to play automatically, this is easily turned off, and the switch that does this has a label reminding Evolve users that turning on autoplay will make the content non-accessible.

Guideline 1.4.3

Contrast (Minimum) Level AA The visual presentation of text and images of text has a contrast ratio of at least 4.5:1


Adequate color contrast between text and the background color must be sufficient; this includes text in images and diagrams, as well as text content on a page. There are a couple of exceptions to this rule: company logos, buttons, clickable objects in a disabled or inactive state, and larger text has a different contrast ratio of 3:1.

What does this mean for your content in Evolve?

There are numerous free automated tools that are specifically designed to measure color contrast from an accessibility perspective, so you don’t have to guess!

They can tell you what ratio and what level of accessibility your content meets. Evolve’s internal QA team uses this color contrast analyzer. Colors in Evolve are adjustable to a huge degree, so you can easily meet this requirement.

 Remember to test early and often, so complex diagrams that may involve a lot of work aren’t created before you have checked the color schemes meet contrast requirements.

Guideline 1.4.4

Resize text Level AA Except for captions and images of text, text can be resized without assistive technology up to 200 percent without loss of content or functionality.


This means that when using a native browser or operating system controls to zoom in to content, content stays legible, does not overlap, and still works as expected.

What does this mean for your content in Evolve?

Evolve content is fully responsive which means it adapts to fit the circumstances in which it is displayed. This means it can still display in a readable way while being zoomed in at 200 percent. If in doubt, you can use your browser's native zoom controls to check your course in live preview at 200 percent zoom.

Guideline 1.4.5

Images of Text Level AA If the technologies being used can achieve the visual presentation, text is used to convey information rather than images of text.


Avoid using text within static images wherever possible. As mentioned previously, company logos are exempt from this rule.

What does this mean for your content in Evolve?

With the flexibility Evolve provides, there shouldn't be a need to present text in an image. If it is absolutely unavoidable, remember to provide a sufficient descriptive alt tag for the image, and also to check for sufficient color contrast.

Guideline 1.4.6

Contrast (Enhanced) Level AAA The visual presentation of text and images of text has a contrast ratio of at least 7:1.


This is the triple A version of 1.4.3 - same principal, but a higher ratio of contrast.

What does this mean for your content in Evolve?

Like guideline 1.4.3, this can be met with Evolve, using a color contrast analyzer tool to measure the contrast ratio of your course content.

Guideline 1.4.7

Low or No Background Audio Level AAA For prerecorded audio-only content that (1) contains primarily speech in the foreground, (2) is not an audio CAPTCHA or audio logo, and (3) is not vocalization intended to be a primarily musical expression, such as singing or rapping, at least one of the following is true:

  • No Background: The audio does not contain background sounds.
  • Turn Off: The background sounds can be turned off.
  • 20 dB: The background sounds are at least 20 decibels lower than the foreground speech content, with the exception of occasional sounds that last for only one or two seconds. Per the definition of "decibel," background sound that meets this requirement will be approximately four times quieter than the foreground speech content


Be aware of the quality and nature of any audio you include in your courses and that background noise is not obscuring or making it hard to hear foreground audio.

What does this mean for your content in Evolve?

Evolve supports audio content in a variety of different components and extensions - there is nothing technical Evolve can do here to fulfill this requirement - rather, you need to be conscious of the audio you are including, whether it’s something you have recorded yourself or something produced by a third party.

What’s the quality of your audio like? Are speaking voices clear and distinct, without background noise? If recording audio or video yourself, consider the location and circumstances of where you are recording - and if you think the level of background noise could be problematic, try and find a different location to record in.

Guideline 1.4.8

Visual Presentation Level AAA For the visual presentation of blocks of text, a mechanism is available to achieve the following:

  • Foreground and background colors can be selected by the user.
  • Width is no more than 80 characters or glyphs (40 if CJK).
  • Text is not justified (aligned to both the left and the right margins).
  • Line spacing (leading) is at least space-and-a-half within paragraphs, and paragraph spacing is at least 1.5 times larger than the line spacing.
  • Text can be resized without assistive technology up to 200 percent in a way that does not require the user to scroll horizontally to read a line of text on a full-screen window.


This is the triple A requirement for presenting text in the most accessible way, and is a mix of technical and presentational requirements. ‘CJK’ above stands for ‘Chinese Japanese Korean’. Something to bear in mind if your course is to be translated into any of those languages.

What does this mean for your content in Evolve?

Points 2 - 5 can easily be achieved in your Evolve content. As referenced above, you can use your browser controls to zoom in to Evolve content by 200%, and the content will display in a perfectly readable way, without the need for horizontal scrolling. Line and paragraph spacing can be manually set to fit those specifications. At the present time, it’s not possible to allow learners to control color schemes for text content themselves - but you can easily set a high-contrast color scheme for your text content if required. Again, talk to your audience and find what works for them.

Guideline 1.4.9

Images of Text (No Exception) Level AAA Images of text are only used for pure decoration or where a particular presentation of text is essential to the information being conveyed.


This is the triple A version of 1.4.5 - and so is concerned with not presenting text as part of images (despite the ‘No exception’ part of this guideline, company logos are still exempt).

What does this mean for your content in Evolve?

If you need to include diagrams or images with text in your course, Evolve can help you present content in a different way - instead of a static image, you could use either the Infographic or Simulation Components as a way to present images with accompanying text labels.

Guideline 1.4.10

Reflow Level AA Content can be presented without loss of information or functionality, and without requiring scrolling in two dimensions.


This means that the learner shouldn't have to scroll both vertically and horizontally to access all content.

What does this mean for your content in Evolve?

Evolve content is presented in vertically scrolling pages, and there is never a requirement to scroll sideways as well as vertically to access content. When using some components such as Simulation, Capture, and Infographic if you use a large background graphic this could trigger sideways scrolling — but this is easily avoided.

Guideline 1.4.11

Non-text Contrast Level AA The visual presentation of the following have a contrast ratio of at least 3:1 against adjacent color(s):

  • User Interface Components: Visual information required to identify user interface components and states, except for inactive components or where the appearance of the component is determined by the user agent and not modified by the author;
  • Graphical Objects: Parts of graphics required to understand the content, except when a particular presentation of graphics is essential to the information being conveyed.


An extension of previous color contrast guidelines, this extends beyond text content to include buttons, links, and graphics.

What does this mean for your content in Evolve?

Evolve is endlessly customizable in terms of color. This includes buttons, links, and other interactive elements. Button color combinations by default have good contrast. If in doubt, use a color contrast analyzer to check. For graphical content, this is something you need to be aware of and test when creating graphics for your course.

Guideline 1.4.12

Text Spacing Level AA In content implemented using markup languages that support the following text style properties, no loss of content or functionality occurs by setting all of the following and by changing no other style property:

  • Line height (line spacing) to at least 1.5 times the font size;
  • Spacing following paragraphs to at least 2 times the font size;
  • Letter spacing (tracking) to at least 0.12 times the font size;
  • Word spacing to at least 0.16 times the font size.


This means by conforming to the above text spacing requirements, nothing breaks or becomes inaccessible.

What does this mean for your content in Evolve?

There are many places in Evolve where you can adjust line height and spacing, either on your course as a whole (via the Component section of your Theme Editor) or within individual interactions.

Adjusting these will not break anything or make content inaccessible. In terms of letter spacing, that is mostly determined by the font used in the course - so as long as an accessibility-friendly font has been used in your course, this criteria can be fulfilled. You can read more about accessible fonts by following this link. 

Guideline 1.4.13

Content on Hover or Focus Level AA Where receiving and then removing pointer hover or keyboard focus triggers additional content to become visible and then hidden, the following are true:

  • Dismissible: A mechanism is available to dismiss the additional content without moving pointer hover or keyboard focus unless the additional content communicates an input error or does not obscure or replace other content;
  • Hoverable: If pointer hover can trigger the additional content, then the pointer can be moved over the additional content without the additional content disappearing;
  • Persistent: The additional content remains visible until the hover or focus trigger is removed, the user dismisses it, or its information is no longer valid.


This talks about content that appears when the user hovers over something on screen, and what the acceptable behavior of that content is.

What does this mean for your content in Evolve?

While you can set certain hover actions in certain places in Evolve (the simulation component is one example) this is always an optional choice and something the course creator has control over.

This point doesn’t preclude the use of such actions - but perhaps the most pertinent point is that content displayed must stay in view when hovered over. For a course compatible with screen readers, text displayed only on a hover action is not advisable - it may be hard to navigate to, and there may be no notification to the learner that additional content has appeared.

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