Business rules manual
RGAA v4.0.0
Theme 9: Structure of information
Rule 9.1.1

Rule 9.1.1

Summary

This test consists in checking the relevancy of the headings hierarchy.

Business description

Criterion

9.1

Test

9.1.1

Description

Dans chaque page web, la hiérarchie entre les titres (balise <hx> ou balise possédant un attribut WAI-ARIA role="heading" associé à un attribut WAI-ARIA aria-level) est-elle pertinente ?

Technical notes (criterion 9.1)

WAI-ARIA permet de définir des titres via le rôle heading et l’attribut aria-level (indication du niveau de titre). Bien qu’il soit préférable d’utiliser l’élément de titre natif en HTML <hx>, l’utilisation du rôle WAI-ARIA heading est compatible avec l’accessibilité.

Bien que la spécification HTML5 autorise l’utilisation exclusive de titres de niveau 1 (h1), le manque de support des technologies d’assistance oblige à utiliser une hiérarchie de titres pertinente.

Level

A

Technical description

Scope

Page

Decision level

Decidable

Algorithm

Selection

Set1

All the <Hx> tags where x is comprised between 1 and 6 and all the tags with a "role" attribute equals to “heading” and an "aria-level" attribute (h1, h2, h3, h4, h5, h6, [role=heading][aria-level])

Process

We assume that the index of the first encountered <Hx> tag represents the index of reference for the document.

Test1

We check that the difference between the index of each element of Set1 and the index of its previous element is not superior to 1.

For each occurrence of false-result of Test1, raise a MessageA

Test2

We check that the index of each element of Set1 is not inferior to the index of reference.

For each occurrence of false-result of Test1, raise a MessageB

MessageA : Header Tag Not Hierarchically Well defined
  • code : HeaderTagNotHierarchicallyWelldefined
  • status: Failed
  • parameter : previous heading tag, snippet
  • present in source : yes
MessageB : Header Tag Not Hierarchically Well defined
  • code : HeaderTagNotHierarchicallyWelldefined
  • status: Failed
  • parameter : first heading tag, snippet
  • present in source : yes

Analysis

Passed

Test1 or Test2 return true for all the elements of Set1

Failed

Test1 or Test2 return false for at least one element of Set1

Not Applicable

  • The page has no <H> tag
  • The page has no tag with heading semantic (role="heading" and aria-level="Integer")

(Set1 is empty)

Files

Rule 9.1.2