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PDF-accessibility-saas/docs_req/Here’s an expanded explanation of PDF-UA-1 (ISO 14289-1).md

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Here's an expanded explanation of PDF/UA-1 (ISO 14289-1), what it covers, why it is important, and its core requirements for your development team:

What is PDF/UA-1 (ISO 14289-1)?

  • PDF/UA stands for PDF Universal Accessibility.
    • ISO 14289-1 is the international standard that defines the requirements for making PDF documents accessible to people with disabilities, especially those who rely on screen readers or other assistive technologies.
  • Purpose:
    • PDF/UA ensures that anyone—including users with visual, mobility, or cognitive impairments—can reliably access, comprehend, and interact with PDF documents using assistive technologies.

Why Is PDF/UA Compliance Important?

  • Legal Requirements: Many regions (such as under the ADA, AODA, Section 508 in the US, and the EU Accessibility Act) require digital documents, including PDFs, to be accessible by law for public sector and large organizations.
  • -Inclusivity: Ensures equitable access for everyone, including people with disabilities.
  • Machine Readability: Facilitates information extraction and automation (e.g., data mining, search).

  • What Does PDF/UA-1 Require?

    • PDF/UA-1 defines a set of technical criteria. For your checker, you'll want to verify that PDFs meet the following requirements:

  • 1. Tagged PDF

    • All content must be represented in the document's tag structure (structure tree).
    • Uses semantic tags (e.g., headings, lists, tables) to express document structure.

  • 2. Text Alternatives

    • All images, figures, and non-text content must have meaningful alternative text (alt text) or be marked as artifacts (decorative).

  • 3. Reading Order

    • The order in which content is presented to assistive technologies must match the intended reading order (logical order).

  • 4. Labeling and Navigation**

    • Headings: Properly tagged (e.g., <h1>, <h2>, etc.) for easy navigation.
    • Lists: Correctly tagged for screen readers.
    • Tables: Rows, columns, headers accurately identified.

  • 5. Unicode Mapping

    • All text must be mapped to Unicode, ensuring screen readers can pronounce it correctly.

  • 6. Document Language

    • The primary document language must be specified.
    • Sections in other languages must be marked accordingly.

  • 7. Titles and Metadata

    • Every PDF must have a descriptive Title.
    • Metadata (author, subject, keywords, etc.) should be included.

  • 8. Form Fields (If Present)**

    • All interactive elements (buttons, form fields) require a programmatically associated label or tooltip.
    • Tab order must match the logical reading order.

  • 9. No Reliance on Visual Only**

    • Information must not be conveyed by color, shape, or position alone.

  • ### 10. **Other Technical Requirements**

  • No elements should be hidden from assistive technologies if they are important.

  • Font embedding, consistent use of artifacts, tab order, and other PDF best practices.

Implementation for an Accessibility Checker

Your tool should verify all the above by:

  • Detecting and analyzing the structure tree.
  • Checking presence and content of alt texts.
  • Validating document language and metadata.
  • Testing tag accuracy for headings, lists, tables, and more.
  • Ensuring tab order and reading order are correct.
  • Checking for missing, unreadable, or incorrectly ordered content.
  • Verifying accessible form fields where interactive elements exist.

PDF/UA Reference (PDF Association) ISO 14289-1 Specification

_ _

Nick Langton (he/him) Global Delivery Director

OLIVER

e: nicklangton@oliver.agency m: +44 (0)7971 828513 w: www.oliver.agency

151 Rosebery Ave, London EC1R 4AB