Technique F38:Failure of Success Criterion 1.1.1 due to not marking up decorative images in HTML in a way that allows assistive technology to ignore them
About this Technique
This technique relates to 1.1.1 Non-text Content (Failure).
This failure applies to HTML.
Failure techniques show examples of how content can fail particular WCAG success criteria. However, content may still satisfy those criteria if it includes equivalent/alternative content or functionality that does meet the normative requirements. See About WCAG Techniques.
Description
This describes a failure condition for text alternatives for images that
should be ignored by AT. If there is no alt attribute at all assistive
technologies are not able to ignore the non-text content. The alt attribute
must be provided and have a null value (i.e., alt="" ) to avoid a failure of this Success Criterion.
This describes a failure condition for text alternatives for images that should be ignored by assistive technology (AT). If an image has the attribute role="presentation", it will be ignored by AT. However, if it does not have role="presentation", and if there is no alt attribute at all assistive technologies are not able to ignore the image. For decorative images which need to be ignored by AT, either role="presentation" must be used or the alt attribute must be provided and have a null value (i.e., alt="") to avoid a failure of this success criterion.
Examples
- Decorative images that have no
altattribute and noroleattribute
Tests
Procedure
For any img element that is used for purely decorative content:
- Check whether the element has no
roleattribute or has aroleattribute value that is notpresentation. - Check whether the element has no
altattribute or has analtattribute with a value that is not null.
Expected Results
- If check #1 and #2 are true, this failure condition applies and content fails the Success Criterion.