This is a draft document supplied by the WCAG Techniques Task Force. It in no way represents a WCAG Working Group consensus or agreement and is provided for informational and discussion purposes only. The accessibility test listed below should not be construed as required for conformance with the proposed WCAG2.
Copyright 2005, ATRC, University Of Toronto, All Rights Reserved. W3C liability, trademark, document use and software licensing rules apply.
This test case was created by the ATRC at the University Of Toronto. It should not be construed as required for conformance with the proposed WCAG2.
The complete list of tests may be found at http://www.w3.org/WAI/GL/WCAG20/tests/
Comments on this test may be made to the WCAG mailing list.
As part of the conformance test process, this test has a status of 'accepted'.
Guideline: 4.1 - Use technologies according to specification.
Success Criteria:
1. Except where the author has documented that a specification was violated for user agent compatibility (including compatibility with assistive technology), the content has: passed validity tests for the version of the technology in use (whether it be conforming to a schema, Document Type Definition (DTD), or other tests described in the specification), and used technology features as defined in the specification.
Level 1
The WCAG2 has 3 priority levels for making Web content accessible. This test has a priority of 'Level 1'.
The WCAG Working Group has created techniques that describe how Web content may be made accessible. The following techniques are related to this test:
The following tests must be run before running this test. If any of the prerequisite tests fail then this test is invalid and should not be run.
img
element, calculate the length of text within the alt
attribute value.alt
attribute value is greater than 100 characters (English) then either shorten the alt
attribute value or confirm that current value is the shortest possible for the associated image.The following tests are related to this test and may be performed next. There is no requirement that these tests be performed:
img
elements is not placeholder text.
img
elements is the empty string ("") if the image is decorative.
img
elements that are not used as source anchors conveys the same information as the image.
This test contains language specific directions and is dependent upon the language of the content. It may be applied only to content written in the following languages:
Language | Maximum Alt text Length |
---|---|
eng | 100 |
ger | 115 |
kor | 90 |
These test files contain examples of the accessibility problem detectable by this test. They may also contain more accessibility problems than the one described in this test. Please ignore any extraneous accessibility problems in these files.
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
<head>
<meta http-equiv="Content-Type" content="text/xhtml; charset=UTF-8" />
<title>OAC Testfile - Check #3 - Positive</title>
</head>
<body>
<p><img src="rex.jpg" alt="A picture of Rex the cat with some extra text. This is very long alt text. In fact, it was much much too long for this image. Sort alt text would be much better and this alt text should be shortened."/></p>
</body>
</html>
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
<head>
<meta http-equiv="Content-Type" content="text/xhtml; charset=UTF-8" />
<title>OAC Testfile - Check #3 - Negative</title>
</head>
<body>
<p><img src="rex.jpg" alt="photo of rex the cat"/></p>
</body>
</html>