Standard
What makes a document accessible
A document is accessible when its structure — not just its appearance — carries the meaning of the content in a form assistive technology can use. The same visual page can be fully accessible or completely opaque to a screen reader depending on a set of concrete, testable features. These are the building blocks that make the difference.
Tags and logical structure. An accessible document is a Tagged document: every piece of content is wrapped in a structure element that says what it is — a heading, a paragraph, a list, a table cell. This structure tree is what a screen reader navigates. Untagged content is invisible to assistive technology even when it is plainly visible on screen.
Reading order. The order in which content is read aloud must be defined explicitly and match the intended logical order. Multi-column layouts, sidebars, and text boxes are where reading order commonly breaks: visually they read one way, but the underlying order can jump around, producing nonsense when spoken.
Alternative text. Every meaningful image, chart, or graphic needs a text alternative that conveys its information or function. Decorative images, by contrast, must be marked as artifacts so they are skipped rather than announced.
Headings and structure. Headings must be marked as real headings in a correct hierarchy (not simply bold, larger text), because screen-reader users navigate by heading. Lists must be marked as lists, and tables must have their header cells identified so a data cell can be related to its row and column headers.
Declared language. The document's natural language must be declared, and language changes within it marked, so speech synthesis pronounces the words correctly.
Forms and links. Interactive form fields must have programmatic labels and be operable by keyboard; links should have meaningful text rather than "click here".
Text, not pictures of text. Content must be real, selectable text — a scanned image of a page is inaccessible until it is put through OCR and tagged. These features correspond directly to WCAG success criteria and to the requirements of PDF/UA (ISO 14289); together they are what "accessible" concretely means for a document.
How Normfluss checks for it
Normfluss inspects a document for exactly these features: it confirms the file is tagged, checks the structure tree is complete and correctly nested, verifies reading order, detects missing alternative text, checks headings, lists and table headers are marked up, confirms the language is declared, and flags images of text that need OCR. The machine-checkable features are automated; whether alt text is meaningful and whether reading order makes sense are routed to human review. The result is a signed record of which features were present and which were fixed — conformance within a stated scope, not a legal determination.