How to Fix the Invalid Use of an LBody Structure Element in PDFs | PAC Tool

In this guide, we’ll learn how to fix the “invalid use of an LBody structure element” error that commonly occurs in PDF documents. You can identify this error using the PAC 2024 tool and Adobe Acrobat Accessibility Checker, essential tools for ensuring PDF UA compliance. Follow the steps outlined here to correct this error and enhance the accessibility of your PDFs.

Video Guide

Understanding the LBody Structure Element Error

Accessibility checkers typically flag the error related to the invalid use of an LBody structure element when the list structure in a PDF does not conform to the expected hierarchy. This issue arises when the list items are not correctly nested, leading to accessibility failures.

Tools for Diagnosis

• PAC 2024 Tool: A tool used for checking PDF/UA compliance.
• Adobe Acrobat Accessibility Checker: Another tool for ensuring that PDFs meet accessibility standards.

Step-by-Step Solution

Step 1: Identify the Error

Run your PDF through the PAC 2024 tool. If you see an error labeled “invalid use of body structure element,” check the same document in Adobe Acrobat Accessibility Checker. The error may appear as “Lbl and LBody failed.”

Step 2: Access the Tags Panel

In Adobe Acrobat, right-click the error and select “Show in tags panel.” This action displays the structure of the list elements within your PDF.

Step 3: Review the List Structure

Next, examine the tags to identify any misconfigured list elements. A proper list structure will have an L (list) tag followed by multiple Li (list item) tags. For nested lists, the structure should include an L tag inside an LI tag.

Step 4: Correct the List Tags

Locate any LBody tags that are incorrectly placed. Each parent L tag must have child LI tags. Right-click the problematic LBody tag, select properties, and change it from “list item body” to “list item.”

Step 5: Adjust Nested Lists

Ensure you correctly tag nested list items. Place the L tag inside the LBody tag for nested lists.

Step 6: Save the Changes

After making the necessary adjustments to the list tags, save the PDF file.

Step 7: Recheck for Errors

Finally, re-run the accessibility check using both the Adobe Acrobat Accessibility Checker and the PAC 2024 tool. Ensure that the error is resolved and no further issues are flagged in the LBL or LBody sections.

Download the Free Section 508 Checklist for PDF Accessibility:

Practical Example

Let’s walk through a practical example:

1. Open PAC 2024 Tool: Identify the “invalid use of body structure element” error.
2. Use Adobe Acrobat: Find the “Lbl and LBody failed” error.
3. Tags Panel: Right-click the error and view in the tags panel.
4. Structure Review: Ensure the list structure is correct with L followed by LI tags.
5. Properties Adjustment: Change LBody to LI in the properties menu.
6. Save and Verify: Save changes and recheck the document in both tools.

Follow these steps to effectively fix the invalid use of an LBody structure element error in your PDFs. This ensures your documents comply with accessibility standards and are usable by all individuals, including those who rely on assistive technologies.

Let me be your champion for inclusion. I offer tailored solutions (and self-paced courses!) to ensure your documents meet and exceed compliance expectations. For more detailed insights, tutorials, and in-depth discussions on accessibility and related topics, don’t forget to check out my YouTube channel: The Accessibility Guy on YouTube. Subscribe for regular updates!