G141 Incorrectly Nested Headings Failure

Lorem ipsum dolor

nonummy

etc. etc.

Explanation

This test page checks for incorrectly nested headings. Headings should be used properly to provide a meaningful outline to users, allowing them to skim the page to get a grasp of the document. Some users may use tools that use heading levels to programmatically generate such outline, so using headings logically - making sure no levels are skipped, mainly - is important.

At AAA level, this warning turns into an error as a failure of Success Criterion 2.4.10 (Section Headings). At lower levels, a warning is emitted: there are examples in technique H42 (Using h1-h6 to identify headings) that suggest order in the document need not necessarily be relative.

Expected Warnings/Errors

• [Standard].Principle1.Guideline1_3.1_3_1.G141: "The heading structure is not logically nested. This h4 element should be an h2 to be properly nested."

Error at AAA level; warning at lower levels. If the first heading is not a h1, the message instead states, eg. "This h4 element appears to be the primary document heading, so should be an h1 element."

Relevant Success Criteria

• SC 1.3.1: Info and Relationships
• SC 2.4.10: Section Headings

Relevant Techniques

• G141: Organizing a page using headings
• H42: Using h1-h6 to identify headings