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Online Accessibility Guidelines

The main way to support students with disabilities is to follow inclusive teaching and assessment practices.The principle of inclusive learning is to guide all staff in the employment of inclusive principles so as to create an inclusive and enabling learning environment in our University. This section offers a range of guidelines on accessibility and resources to enable staff to embed inclusive principles within their teaching and assessment practices:

The following five accessibility guidelines focus on the most common features of online content. When creating online content the creator may often use downloadable items like PDFs. To enhance the look of the content elaborate text size, colours, fonts as well as images, tables, audio and video are also used. These can have considerable unintended impacts on the accessibility of the online content.

Guideline 1: Using PDFs

Avoid using PDFs. Online content, where possible, should be published as HTML web pages and not in PDF format. This will mean that as many people as possible, including people with disabilities, can use the content.

  • PDFs do not work well with assistive technologies, such as screen readers. A screen reader is a piece of software for a blind or visually impaired person. Most screen readers work by using a synthetic voice to read the text aloud. 
  • PDFs do not meet the range of accessibility needs, for example, not being able to change colours or font size.
  • PDFs do not work with many browsers, tools and extensions, for example, people often have problems with zoom, scroll, audio, images and keyboard navigation.

 Guideline 2: Graphics and Images

Do not place text in an image because screen readers cannot read it.

Always use the alt text (text alternative) feature when including images online so they are accessible to screen readers. Use the alt text describes the information or function represented by the image. It gives people who can’t see an image the some information about it. The alt text should not be a literal description of the image. It should explain what point the image is making.

Alt text ensures that images make sense to people with various disabilities, including those:

  • using screen readers - the text alternative can be read aloud or rendered as Braille
  • using speech input software - users can put the focus onto a button or linked image with a single voice command
  • browsing speech-enabled websites - the text alternative can be read aloud

Simple rules for alt text are to keep it concise, clear and straightforward and just describe the image.

If the image is more complex like a graph or diagram, provide a full-text equivalent of the data or information provided in the image as the text alternative.

Do not use buttons and instead use text. For example, use the word “Search” instead of a magnifying glass image. Logo images must be clearly identified as such.

Guideline 3: Text on screen

Plain language benefits all users, including people:

  • with cognitive disabilities
  • with low reading literacy
  • whose first language is not English
  • who are trying to understand a topic for the first time

Use simple language and formatting with short, clear sentences and paragraphs.

When presenting content it is necessary that, lists, tables and other structures in the content be marked-up properly and that sequences of information or instructions must be independent of any presentation. This allows content to be correctly read aloud, enlarged, or adapted to meet the needs and preferences of different people. For instance, it can be presented using a particular text size or other adaptations to facilitate reading.

Distinguishable content is easier to see and hear when:

  • Ideal font style is Sans Serif, recommended font size 12 and paragraph spacing 1.5
  • Paragraph text should be formatted left aligned
  • the colour is not used as the only way of conveying information or identifying content
  • there is enough contrast between foreground and background colours to easily distinguish content
  • text is resizable up to 200% without losing information using browsers or functionality
  • images of text are resizable or replaced with the actual text
  • users can pause, stop, or adjust the volume of audio as it is read

These options are suitable for people who do not use assistive technologies as well as for people using them. For example, people with colour blindness rely on a good design with enough colour contrast between text and background. Also background audio automatically played, could interfere with screen readers.

Guideline 4: Tables

Tables should only be used to display data. Data tables are used to organise data in a logical grid to show the relationships. When tables are used, it is important to ensure that no cells are left empty. For accessibility, tables must include header cells and data cells and define their relationship. Assistive technologies use this information to provide context to users. Tables without structural mark-up to differentiate properly between the row and column headers and data cells, create accessibility barriers. With structural markup, screen readers can read the row and column headers as users navigate through the table.

Guideline 5: Video and audio

All video and audio controls should be accessible with the keyboard so include a player stop, start and pause if possible.

When using pre-recorded or live video and audio it should include the following features:

  • Include captions (subtitles)
  • Include an audio description - if the audio does not present the necessary visual content
  • For a speech, they must include dialogue, identify who is speaking and notate sound effects and other significant audio.

For more information please contact our Assistive Technology Officers here: