1.1.1 Non-Text Content: All non-text content that is presented to the user has a text alternative that serves the equivalent purpose, except for the situations listed below:
- Controls, Input: If non-text content is a control or accepts user input, then it has a name that describes its purpose.
- Time-Based Media: If non-text content is time-based media, then text alternatives at least provide descriptive identification of the non-text content.
- Test: If non-text content is a test or exercise that would be invalid if presented in text, then text alternatives at least provide descriptive identification of the non-text content.
- Sensory: If non-text content is primarily intended to create a specific sensory experience, then text alternatives at least provide descriptive identification of the non-text content.
- CAPTCHA: If the purpose of non-text content is to confirm that content is being accessed by a person rather than a computer, then text alternatives that identify and describe the purpose of the non-text content are provided, and alternative forms of CAPTCHA* using output modes for different types of sensory perception are provided to accommodate different disabilities.
- Decoration, Formatting, Invisible: If non-text content is pure decoration, is used only for visual formatting, or is not presented to users, then it is implemented in a way that it can be ignored by assistive technology.
*CAPTCHA - Completely Automated Public Turing test to tell Computers and Humans Apart
Explanation
On the Web, non-text elements include images, graphical data, aesthetic decorations, audio-only media, video-only media, and synchronized media (movies). Both Web-based and native software applications often use non-text elements as controls or to indicate input.
Audiovisual non-text elements, including audio-only files, video-only files, and synchronized media, require text alternatives. These are considered in more depth in other chapters.
The Success Criteria for non-text content supports the principle of Perceivable because people who are without vision cannot perceive images; AT (specifically screen readers) needs descriptions of images to provide that information. Likewise, people who are without hearing are unable to perceive audio content and need a text alternative.
Success Criteria 1.1.1 is the longest of all the Success Criteria. The intent of this Success Criteria is to ensure that all users perceive equivalent information, even if the information is not in text format. Success Criteria 1.1.1 requires that an equivalent text alternative be provided for non-text content so that the same information is available to all users, including those using AT. Text is used as an alternative format for non-text elements because it can be rendered in a variety of methods. For example, without the use of AT, a transcript of a sound recording can provide access to a person who is without hearing or who has limited hearing; while with the use of AT, alternate text provided to identify an image can be read with a screen reader for someone who is without vision.
There are some exceptions to the requirement to provide a text alternative to non-text elements. Putting equivalent alternative text on these items is either just not feasible or is distracting to people using screen readers rather than helping them understand the content on the page. However, if the content is not marked in any way, users may try to guess the content or assume they are missing information (even though the non-text content is superfluous). This type of non-text content is either marked or implemented in a way that AT will ignore it, OR a short text alternative that is not equivalent is most appropriate.
Note: In HTML, non-text elements use an attribute called “alt” to allow inclusion of alternate text descriptions. Having no ALT attribute is not the same as providing a null value <alt="">—two quotation marks without a space—or an empty value <alt=" ">—two quotation marks with a space. A screen reader will recognize a null or empty value and skip over it. However, if there is no ALT attribute provided, a screen reader will alert the user to the presence of the non-text element, but it will be unable to provide any helpful information about it (most likely only the file name). Users will have to guess if the non-text element is meaningless, or if it has content that they are missing.
Impact of Nonconformance with SC 1.1.1 Non-Text Content
| Type of Disability | Description of Impact |
|---|---|
| 302.1 Without Vision | Users who are blind cannot use a mouse to interact with electronic content and typically use an assistive technology, such as a screen reader, to get audible or other alternative output for the information represented visually. To be able to navigate the content, understand its structure and relationships, and understand the meaning of content represented in graphics and images, the content must provide textual and programmatic cues in addition to the content presented purely visually. |
| 302.2 With Limited Vision | Users with limited vision may have widely different visual perception. Individuals with limited vision may or may not use assistive technologies. Therefore, in addition to textual and programmatic cues necessary for assistive technologies, ICT must also present content consistently and predictably. Users who view content with magnifiers may not pick up alerts, warnings, or other content if such content is presented outside of a consistent and predictable navigation pattern or if the content is not itself viewable at large magnification. Content that becomes distorted when magnified can also prevent some users with limited vision from being able to understand or interact with the content. |
| 302.4 Without Hearing | When ICT provides information, instructions, or cues audibly, users who are deaf will not receive the information. Typically, providing the same information visibly (e.g., providing a warning light or textual dialog to accompany an audible warning sound or captions for audio dialog and other audible information in a video) will enable users who are deaf to get equivalent information. |
| 302.5 With Limited Hearing | Some users cannot hear sounds below certain volumes or at certain frequencies and may not be able hear certain audio outputs from ICT. Background noise can also be problematic for users with limited hearing. Providing modes of operation that enhance audio clarity (e.g., filtering out hisses and pops, blocking sounds at specific frequencies, normalizing voice volumes, removing constant tone patterns), increase the range of volume, increase volume at higher frequencies, and/or give users control over such settings can help users with limited hearing understand, navigate, and operate the ICT. Users with limited hearing may also benefit from some of the same methods used to provide information to users without hearing. |
| 302.9 With Limited Language, Cognitive, and Learning Abilities | Some users require more time than average to process information while others may find complicated instructions difficult to follow. Furthermore, some ICT content can distract or overwhelm users, preventing them from being able to interact with or understand other ICT content. Designers and developers of ICT must consider a broad range of cognitive abilities in order to provide ICT that is simple and easy to use. |
Applicability of Success Criteria 1.1.1 Non-Text Content
| Technology | Applicability of SC 1.1.1 |
|---|---|
| Web | Applies directly; developers can provide text alternatives for non-text content using a number of methods. Typical methods include associating text alternatives using, alt, aria-label, aria-labelledby, aria-describedby, and/or title attributes as well as other text provided in context. |
| Software | Applies directly; developers can typically provide text alternatives for non-text content by providing alternate text using the native software accessibility programming interfaces name and/or description property. |
| Office documents | Applies directly; content authors can provide text alternatives for non-text content, such as images, using the Alt attribute in the authoring tool. |
| PDF documents | Applies directly; content authors can provide text alternatives for non-text content, such as images, using the Alt attribute in the authoring tool. |
| Mobile native | Applies directly; developers can typically provide text alternatives for non-text content by providing alternate text using the native software accessibility programming interfaces name and/or description property. |