About this website
PDF document
On this page
- PDF document
- Tags
- Custom tags
- Reading order
- Alternative text
- Simple data tables
- Complex data tables
- Document title
- Language
- Bookmarks
- PDF forms
- Label and required fields
- Error prevention
PDF document
Overview
Use the built-in Accessibility Checker to test a PDF for many common issues. Results are classified as:
- Pass means the category meets accessibility requirements as far as the automatic checker can tell.
- Needs manual check indicates the automatic checker can't test this category so you need to review it yourself.
- Failed means you must fix some
Note: Automated checkers cannot test all possible issues. The Accessibility Checker will warn of some considerations such as colour contrast and logical reading order, which always need human review.
However, you'll also need to manually scrutinise other possible issues, like uninformative text alternatives and non-descriptive headings.
Techniques
Launch the Accessibility Checker
First add Accessibility to the Tool pane on the right of screen.
- Choose the Tools
- Add
- Add Edit PDF and Prepare Form because we'll use these tools
To run the Accessibility Checker:
- Choose Accessibility, Full
- To add a report to your PDF file, choose Create Accessibility Report
checkbox, and select a folder to save it in.
- Click the Start Checking
Interpret the results
A report summary loads from the Acrobat Pro Navigation Pane.
- Checks that pass Acrobat's requirements are ticked (✔).
- Checks that fail have a cross (x).
- Checks that need manual review have a question mark (?). Update the checker after you have fixed any
Manual review
- Right-click on the needs manual check icon (?).
- Choose Pass.
Fail
- Right-click on the fail icon (x).
- Choose Check
The report will update if the issue has been resolved.
Tags
Overview
You must tag all PDF content correctly for screen reader users to fully understand it.
Tag information is structured into a hierarchical tree that you can expand or collapse by clicking the plus sign (+) or the minus sign (-).
Commonly used tags include:
- <H1> to <H6> for headings
- <P> for paragraph
- <L>, <LI>, <Lbl> and <Lbody> for lists and list items,
- <Figure> for
- <Table>, <TR>, <TH>, <TD> for tables, table rows, header cells and data cells
When you export correctly from Word, your document will show these tags in their tag tree.
Techniques
Check the tags of a PDF
- Open the Tags
- Check that the tags are
- Choose Highlight Content from Tag Options drop-down
- Check that content is tagged correctly, that is headings are tagged as heading tags (for example, <H1> to <H6>), Lists are tagged as list tags (for example, <L>, <LI>) and so
Add tags
If the PDF shows no tags in the tag tree, you must add tags. To add tags:
- Open the Tags panel
- Choose Add Tags to Document from the Options menu
- Check tags carefully and update where
Update tags
- Right-click on the tag to be
- Select
- In Object Properties, Tag choose another tag type from the Type drop- down list
Custom tags
Overview
Documents exported from other applications like InDesign may show ‘custom' tag name(s), for example ‘Heading_1' (see below). You can see the ‘true' tag that each custom tag maps to in the document's Role Map.
In the example here, the custom tag Heading_1 is mapped to the true H1 heading tag. However, Heading_2 and Heading_3 are incorrectly mapping to the paragraph <P> tag, so a screen reader will not announce them as headings.
Techniques
Check and update the Role Map
- Open the Tags
- Right-click a tag and choose Edit Role Map.
- Choose a custom style with an incorrect
- Choose Change
- Update the reference value in the Change Value
Reading order
Overview
An illogical screen reader reading order means screen reader users will hear content in an illogical order.
Techniques
Ensure that the visual reading order and screen reader reading order are the same. Remember to check that the reading order for all floating images and text boxes are correct.
Check the reading order
- Open the Navigation pane, then select Order.
- Choose Accessibility Tools, then Reading Order to display numbered content
- Check that content blocks are listed in the correct reading
Note: The content blocks in the example above are listed in incorrect sequence, so a screen reader will not announce them in a logical order.
Changing the reading order
- In the Order panel drag a piece of content up or down to the required
- Note: This will also update tag
Alternative text
Overview
Informative images
Screen readers will announce the alt text for images. If you applied alt text in the Word source document, it will remain in the PDF.
Note: when adding alt text in MS Word only use the ‘description' field, leave the 'title' field blank.
Decorative images
Set decorative images to Background or Artefact. Screen readers will ignore these images.
Note: if you know the document will become a PDF, you can leave the alt text blank in Word and set it as a background image in PDF. If it's staying in Word format as well, write ‘decorative' as the alt text and still mark it in PDF.
Techniques
Provide alternative text for informative images and hide decorative images from screen readers.
Checking alt text
- Select Tools, Reading
- Confirm that the alt text of images correctly identifies image
Adding or changing alt text
There are several ways to add alt text. Here is the most straightforward one:
- Right-click on the
- Select Edit Alternate
- Enter your alt text in the Alternate Text
Hiding decorative images from screen readers
There are several ways to hide decorative images. Here is the most straightforward one:
- Choose accessibility tools, Reading order
- Draw a rectangle around the decorative image with your mouse to highlight it.
- In touch up Reading Order click on background.
Alternatively, review and set the alt text for all images in the document using the following approach8:
- Select Set Alternate Text from the Accessibility tools.
- Select the checkbox Decorative figure for any decorative images.
Simple data tables
Overview
Check that:
- table header cells are tagged as <TH>
- table data cells are tagged as <TD>.
Techniques
Update table header tags
- Open the tag
- Change each header tag from <TD> to <TH>.
Complex data tables
Overview
The objective of this technique is to:
- allow screen readers to correctly announce cell data with multiple headers in complex tables
- add a Table Summary to explain a complex table structure, if
Techniques
Assign header properties
- Choose Tools, Reading Order and select the table by clicking its
- Choose Table Editor in Reading
- For each header cell:
- Right-click Table Cell
- Check that Type is correctly identified as Header Cell.
- Set the Scope to Row, Column or Both.
- Check that the number of rows and columns spanned by the header is
- Allocate a unique ID value to the header
Link data cells with each header cell
Open table editor
- For each data cell:
- Right-click Table Cell
- Check that Type is correctly identified as Data Cell.
- Verify that the number of columns and rows spanned by the cell is
- Link Associated Header Cell IDs by choosing each sequentially using the green plus
Techniques
Create a table summary
- Choose the Reading Order
- Locate the table and right-click on the
- Select Edit Table
- Enter a description in the Table Summary
Document title
Overview
Check and assign a descriptive document title. It will carry across from the source file (Word or InDesign) if specified in the PDF Export process.
Techniques
Add or update the document title
- Choose File,
- In Document Properties select the Description
- Add the document title in the Title Make sure this does not include quote marks.
Show the document title
The document title display until this option is chosen as the Initial View, and the document is saved.
- Select File,
- In Document Properties select Initial
- Choose Document Title in the show drop-down
Language
Overview
Choose the correct language for the content of the document.
Techniques
Choose document language
- Select File,
- In Document Properties select
- Choose a language in the Language drop-down list, for example English.
Update language variations
If the document contains content in a language other than the language set for the document (for example, a paragraph of French content), you must identify the language for that content.
- Open the Tags
- Right-click on the tag text in a different
- Select
- In Object Properties choose Tag, then a language from the Language drop-down list.
Bookmarks
Overview
Check that the PDF document has bookmarks. Bookmarks are normally imported automatically from the source document.
Techniques
Add Bookmarks
If the document does not have bookmarks, you can add them manually.
- Open Navigation pane,
- Open the Options drop-down menu and select New Bookmarks from Structure.
- Select the Structure Elements you would like as Generally, best practice is to use headings.
PDF forms
Form fields
Overview
You should place form fields where readers will expect to find them.
- Place radio buttons and tick box fields before their
- Place text boxes, drop-down and other form fields after (or below) their input
It's easiest to add visible labels with the source application (such as Microsoft Word). However, you can add them from Adobe Acrobat Pro's Edit PDF function.
Techniques
Add form fields
- Select Tools, Prepare
- If Select a file or scan a document to begin is shown, ensure that field detection is off by clicking Change and unchecking the preference Automatically detect form fields.
- Click Start.
- Click a form field type in the Prepare Form toolbar, then click the logical position for that form field – next to its visible
-
Type a name for this form field, for example ‘email'. The field name should be similar to the visible
- Repeat to add other fields and field
Note: Use exactly the same field name for all radio buttons in a group so the user can easily tell they all belong to the same group.
Labels and required fields
Overview
Explain requirements for mandatory fields, as well as fields with input requirements. You must use field Tooltips, which screen readers announce as labels.
Techniques
Add Tooltip
- Double-click a form
- Replicate the visible label in the Tooltip.
- Ensure the tooltip indicates if it is mandatory, for example First name required.
- Make sure to check required for mandatory
Note: Radio buttons in a group should share a common Tooltip.
Error prevention
Overview
Help users input the correct data by formatting form fields. This should reduce the number of user mistakes.
Techniques
Set formatting requirements
- Choose Tools, Prepare
- Right-click on the form
- Select Properties, then
- Choose field format requirements from the Select format category.
Set character limit
- Choose Tools, Prepare
- Right-click on the form
- Select Properties, then
- Select Limit of checkbox and enter the maximum number of
Note: You can set simple form validation