2.4 Making display elements adjustable
Individuals may view your content using a range of different devices, screens and browsers. However, there are some common features that you can control to ensure the materials display in a form that is accessible to a wide audience.
The first is to use as default an accessible combination of settings. It is good practice to use a font type that has good readability. Sans serif fonts (such as Arial and Calibri) are often recommended for printed materials because their simpler letter shapes are easier to read. Online, some serif fonts (such as Times New Roman) can be suitable if they are not cursive or uneven. Use a font size of at least 12 point in text documents and 20 point on presentation slides.
Colour combinations should give good contrast. There is a free tool, contrast checker [Tip: hold Ctrl and click a link to open it in a new tab. (Hide tip)] , which helps you assess the contrast of colour combinations: you should aim for a minimum ratio of 4.5 to 1 throughout, and for large amounts of text you should aim for a ratio of 7 to 1.
Avoid using flashing or moving elements unless there is a way for users to stop the movement. Also, avoid putting text over background images – doing this makes it much more difficult to read.
The second element of ensuring the accessibility of the display of your materials is to put control into the hands of the student. If you provide documents created accessibly, students will be able to select their preferred font, colour, and so on. If you are presenting materials to be viewed in a web browser, provide links to guidance on how browsers can be used to meet some accessibility needs and preferences (such as these resources for Firefox, Chrome, Safari, Android and iOS). If you are using another kind of platform to deliver your online material (via web conferencing, learning management system, etc.), try to find out what accessibility features it has and give guidance to your students on how to find and use them.