This guide intends to help you to quickly look up techniques that you use to make PDF documents more accessible. The guide is based on the features found in the Reading Order Tool, PDF document properties and others available in Adobe Acrobat Pro. All screenshots come from Adobe Acrobat Pro DC.
If you don't already have your Acrobat workspace set up with accessibility tools, please see the guide for setting up accessibility tools in Acrobat.
Use “Make Accessible” to Start with Untagged PDF Documents
The Make Accessible Wizard gives you a pretty good starting place when you have an untagged PDF document. The Action Wizard is on the right of the Acrobat Pro window.
- Select Action Wizard > Make Accessible.
- Follow prompts.
The Wizard will ask you to provide a Title, the language of the document, alternative text for figures, and more. If you need to change some properties in an existing, tagged PDF then the following will help:
Add Alternative Text to Meaningful Images and Figures
Alternative Text conveys the intended meaning of an image or figure. Acrobat Pro DC now lets you set alternative text on all images in a file. Find this option under Accessibility Tools > Set Alternate Text.
- A dialogue box appears telling you that Acrobat will find all the images and let you edit or add alternative text.
- Click the OK button.
- Acrobat will show you the image and a dialog box where you can edit or add alternative text.
- Use the arrow buttons to move from one image to the next, adding meaningful alt text if applicable. Use the check box for "Decorative" if the image doesn't convey meaningful information.
In earlier versions of Acrobat, you can set the alternative text as follows:
- Navigate to Accessibility Tools > Reading Order > Touch Up Reading Order Tool.
- Select the image.
- Right click or use Shift + F10 and select Edit Alternate Text.
- Type alternative text into the field in the dialog box.
Create or Edit Heading Tags
Use the Reading Order tool to make section and subsection headings into accessible headings. The Reading Order tool offers 6 levels of headings. To make a heading:
- Start Reading Order Tool (under Accessibility tool in Tools Pane).
- Select heading text with the tool's cross-hairs.
- Select the appropriate heading level in the Reading Order pane.
- Verify that the heading is the correct heading level in the Tag Tree.
You can also add a heading by using the selection tool. To do so, follow these instructions:
- Create a new heading tag in the Tag Tree by right-clicking an existing tag, or using Shift + F10, to open the context menu and selecting New Tag. (The new tag will be added below the one you opened the menu from).
- Select the text within your document by using the Selection Tool. To navigate between task panes to get to the Selection Tools, use F6.
- Open the context menu on the tag you just created, and select Create New Tag from Selection.
Identify Table Headers
Tables with a simple structure are much easier to make accessible. Complex structures, with nested headers and merged cells, take more effort. With a simple table:
- Find the table's tag in the Tag Tree.
- Right-click (or use Shift + F10) to open the tag's context menu, and then hit Q to open the Table Editor.
- Select header cells by clicking one at a time, or clicking and dragging a line across multiple cells.
- Right click the selection and select Table Cell Properties.
- Set Type to Header.
- Specify whether header(s) apply to columns or rows in the Scope drop-down menu.
- Select the OK button.
When Color Conveys Meaning, Use Color Plus Another Visual Cue
Use markers, text labels or different patterns for charts and graphs
Use additional formatting for text, or a symbol such as an asterisk
Required fields are in dark red
Color plus another indicator:
Required fields are in red and marked "required"
First Name (required)
NOTE: The Accessibility Checker in Acrobat will warn you to check this, but his is something that you most often need to consider before conversion to PDF.
Use Good Color Contrast
Check that contrast between text and background colors is at least 4.5:1 for regular text and 3.0:1 for large text.
NOTE: The Accessibility Checker in Acrobat will warn you to check this, but his is something that you most often need to consider before conversion to PDF. The Paciello Group Colour Contrast Analyser lets you easily check color contrast.
Create Accessible Links
Make descriptive link text the active link in a document, and put the actual web address (URL) in plain text. This makes sure that people can use the link whether the document is digital or printed. To make a link that is interactive and properly structured in the Tag Tree, use the Selection Tool
- Using the Selection Tool, select the text that serves as descriptive link text.
- Right click and choose Create Link from the pop up menu.
- Follow the prompts in the Create Link dialog box to create an interactive and accessible link.
After the link is done, the Tag Tree should have the link text in a Link tag along with a “Link – OBJR” tag.
Check Reading Order
Reading order can be very different for people that use screen reading software than it is on the visible page. Make sure that the reading order in the Tag Tree matches with the visible reading order of the document. Drag and drop tags in the tag tree using the mouse or use Ctrl+X and Ctrl+Z to cut and paste to put tags in the correct order.
Acrobat Pro has an accessibility checker that is worth using. It is easy to run:
- Find the tool under Accessibility Tools > Accessibility Check.
- Verify options in the list that appears in the Accessibility Checker Options dialogue box.
- Start the check with the Start Checking button.
This will create an easy to navigate report that flags things like missing alternative text for images.