Q. Accessibility - Use Long Descriptions for Complex Graphs, Charts, Tables and Images

Accessibility - Use Long Descriptions for Complex Graphs, Charts, Tables and Images

Use Long Descriptions for Complex Graphs, Charts, Tables and Images

Tip: Use long descriptions when any of the following are true about an image or visual content:

• Complex data is presented (e.g., charts, graphs) 

• There are meaningful relationships or multiple elements (e.g., flowcharts, schematics) 

• The visual information is essential for understanding the content or completing a task 

• The image cannot be fully described with alt text alone 

Why it matters: Long descriptions provide essential information for users who cannot perceive visual content. They are particularly important for users of screen readers, people with cognitive disabilities, and users with low vision. Long descriptions are not the same as alt text and provide detailed representation of the data or object being presented.

Details to Include: As with alt text, it may not be necessary to describe every bit of the complex image, graph, or table, but it is important to include everything that is meaningful. Some strategies for accomplishing this are to

• Explain the purpose of the image,
• Identify all significant elements and their relationships, and
• Include any labels, titles, values, and captions visible in the image.
• Summarize patterns and highlight key findings.

How to do it: Where Does the Long Description Go?

Long descriptions can be added included in several ways:

• Inline descriptions - are placed either before or after the image and are most useful if the description is relatively short and directly relevant. If you are comfortable with HTML, you can use a collapsible panel (using the
  and

  tags) to provide an accessible, on-page experience.

• Captions – if the long description is only a few sentences, you can place it in the image’s caption field (similar to how you add alt text in many programs). If available, captions will keep the description attached to the image.

• Adding a caption in MS programs
• Adding a caption in Adobe PDF
• Adding a caption in HTML

• Links to a long description – use this option if the description is very long and would interrupt the flow of the nearby text, or if captions are not an option. This is most useful on Canvas or web pages, but it is also possible to create links within a Word or PowerPoint file that point to an appendix with the description. When creating the link, make it visible and clearly labeled (e.g. Detailed description of the organizational chart).
• The Notes area of a PowerPoint slide deck can be used for long descriptions of content on specific slides.

Alignment:
Web Content Accessibility Guidelines (WCAG) 1.1.1