PDF Accessibility#

Colectica Designer, Colectica Portal, and Colectica Questionnaires generate PDF documents using the Typst typesetting system, which is included with Colectica. This page describes the accessibility standards those PDFs meet, the accessibility features they include, their known limitations, and how to check a generated PDF yourself.

Standards#

PDF/UA-1

Generated PDFs are produced against PDF/UA-1 (ISO 14289-1), the international standard for accessible PDF, and declare their conformance in the document metadata. Typst enforces the standard’s requirements while the document is compiled, and sample documents in each style pass PDF/UA-1 validation with veraPDF.

Tagged PDF

Every generated PDF is a tagged PDF. Tags describe the document’s structure, such as paragraphs and tables, and the order in which assistive technologies such as screen readers read the content.

PDF/A

PDF/A (ISO 19005) is a standard for long-term archiving, not for accessibility. Only its “a” conformance levels, such as PDF/A-2a, require tagging. Generated PDFs do not currently declare PDF/A conformance.

WCAG, Section 508, and EN 301 549

The Web Content Accessibility Guidelines (WCAG) apply to PDF documents as well as to web pages. Section 508 in the United States and EN 301 549 in the European Union both reference WCAG. PDF/UA covers how a PDF is built. WCAG also covers the content itself, such as color contrast and meaningful headings, which software cannot fully check. See Known Limitations for the WCAG topics generated PDFs do not yet fully address.

Accessibility Features#

Generated PDFs include the following features.

  • A tagged structure with a logical reading order.

  • Headings. The document title is a first-level heading, and section, item, and variable titles are headings nested beneath it, so screen reader users can jump between sections.

  • Data tables, such as frequency tables, code lists, and summary statistics, tagged as tables. Column headings, such as the value and label headings on code lists and the frequency and percentage headings on frequency tables, are tagged as header cells, so assistive technologies can announce the column heading for each value.

  • Text colors with a contrast ratio of at least 4.5:1 against the page and tinted backgrounds, as WCAG 2 Level AA requires for normal text.

  • A document title, which PDF viewers display in the title bar instead of the file name.

  • A document language, taken from the language chosen when the document is generated. Screen readers use it to choose a pronunciation.

  • Bookmarks (a document outline) for navigating between sections.

  • Embedded fonts with Unicode mappings, so text can be searched, copied, and read aloud.

  • Running headers, footers, and page numbers marked as artifacts, so screen readers do not read them as part of the content.

  • Alternative text for the organization logo when it appears on its own. When the logo appears beside the organization name, it is marked as decorative, because the name already identifies it.

Known Limitations#

Colectica v7 frequency tables

In the Colectica v7 style, frequency tables keep the layout of earlier versions of Colectica, which has headings for the frequency and percentage columns only. The group, value, and label columns have no headings.

One language per document

The document declares a single language. Text that falls back to another language, such as a question without a translation, is not marked with its own language.

Custom cover pages

A custom cover page is written by your organization, so its content is your responsibility. Give every image on a cover page alternative text, for example #image("cover.png", alt: "Agency logo"). If a cover page, or other custom content such as an addin template, does not meet PDF/UA-1, Colectica still produces a tagged PDF. That PDF does not declare PDF/UA conformance.

Paper questionnaires

The paper form is designed for printing. It is not a fillable PDF form.

Checking a PDF#

Automated checkers verify the machine-checkable parts of PDF/UA. A person still needs to review items such as reading order, the quality of alternative text, and color contrast.

veraPDF

veraPDF is a free, open source validator for PDF/UA and PDF/A, developed by the veraPDF Consortium. It runs on Windows, macOS, and Linux, and includes a command line tool suitable for automated checks. To check a PDF against PDF/UA-1, run verapdf -f ua1 document.pdf.

PAC

PAC is a free Windows application that checks PDF/UA and WCAG requirements and includes a screen reader preview.

Adobe Acrobat Pro

The Accessibility Check in Adobe Acrobat Pro produces an accessibility report. It always lists some rules, such as logical reading order and color contrast, as needing manual checks.

Screen readers

Reading a document with a screen reader such as NVDA, JAWS, or VoiceOver shows how it is experienced by people who use assistive technology.

Accessibility Conformance Reports#

Your organization may need to document the accessibility of the software it buys, for example under Section 508 in the United States or EN 301 549 in the European Union. This is usually done with an Accessibility Conformance Report (ACR), written using the Voluntary Product Accessibility Template (VPAT). To request an ACR for Colectica Designer, Colectica Portal, or Colectica Questionnaires, contact Colectica.

If your organization publishes generated documents, for example on a public website, it is responsible for the accessibility of what it publishes. The accessibility of a generated document also depends on its content, such as labels, descriptions, translations, and the alternative text on custom cover pages. Use Accessibility Features, Known Limitations, and Checking a PDF to evaluate your documents.