How does WCAG apply to PDF?

WCAG has success criteria at levels A, AA and AAA. Meeting AA also requires meeting level A. A law or contract may reference an older version than WCAG 2.2, so state both the version and level.

WCAG2ICT explains how WCAG can apply beyond web content. It is informative guidance, not a separate conformance standard.

Sources: [1], [2]

Perceivable concerns access to information. A chart distinguishing series only through red and green may need labels or line patterns. Its text alternative must also convey the information unavailable to a reader who cannot see the chart. This also includes information and relationships under 1.3.1, such as a table cell’s association with its headers being available beyond the visual grid.

Operable concerns using document functions. Links need to be reachable and activatable with a keyboard. In a form, fields, their sequence and any error messages need to work together. Reading a printed field label is not the same as being able to complete the field.

Understandable includes language and predictability. The document language helps speech software choose pronunciation. Instructions should explain the required action, particularly when mistakes have consequences. Plain language also helps, even when a particular editorial improvement is not a separate requirement at the selected WCAG level.

Robust concerns interpretation by software and assistive technology. A form field needs a programmatically determinable name, role and relevant value information under 4.1.2. A visible label is insufficient if assistive technology cannot associate it with the field.

Suppose a PDF contains an image of annual costs. Start with criterion 1.1.1, Non-text Content: is there a text alternative serving an equivalent purpose? Inspect the image and read its alternative. “Costs” names the subject but may omit the message. If it compares three years, readers need that comparison, perhaps through a short description and an accessible data table.

For the table, consider 1.3.1, Info and Relationships: can readers identify the row and column for each value? For 1.3.2, Meaningful Sequence, read its explanation and the table in the order delivered to assistive technology. The questions overlap in one document component but assess different properties.

A useful finding might read: “The page 6 chart’s text alternative omits the comparison. The following table contains the values but lacks header relationships. Readers cannot reliably associate 420 with 2025.” The person fixing it now knows both which information needs explanation and which structure needs repair.

That observation is more useful than a document-wide percentage. One failure can block the central task, while many repeated minor failures may share one cause. Assess consequences and coverage, rather than counting red marks alone.

W3C’s PDF techniques illustrate possible solutions. They do not replace the success criteria and are not the only ways to meet them. Following a heading technique establishes nothing about the document’s images or contrast.

Record the criterion, document location, expected behaviour, observed result and method. Distinguish pass, failure and not applicable. Do not mark something not applicable merely because a tool has no test for it.