Understanding WCAG 2.0

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Sensory Characteristics:
Understanding SC 1.3.3

1.3.3 Sensory Characteristics: Instructions provided for understanding and operating content do not rely solely on sensory characteristics of components such as shape, size, visual location, orientation, or sound. (Level A)

Note: For requirements related to color, refer to Guideline 1.4.

Intent of this Success Criterion

The intent of this Success Criterion is to ensure that all users can access instructions for using the content, even when they cannot perceive shape or size or use information about spatial location or orientation. Some content relies on knowledge of the shape or position of objects that are not available from the structure of the content (for example, "round button" or "button to the right"). Some users with disabilities are not able to perceive shape or position due to the nature of the assistive technologies they use. This Success Criterion requires that additional information be provided to clarify anything that is dependent on this kind of information.

Providing information using shape and/or location, however, is an effective method for many users including those with cognitive limitations. This provision should not discourage those types of cues as long as the information is also provided in other ways.

In some languages, it is commonly understood that "above" refers to the content previous to that point in the content and "below" refers to the content after that point. In such languages, if the content being referenced is in the appropriate place in the reading order and the references are unambiguous, statements such as "choose one of the links below" or "all of the above" would conform to this Success Criterion.

WCAG was designed to apply only to controls that were displayed on a web page. The intent was to avoid describing controls solely via references to visual or auditory cues. When applying this to instructions for operating physical hardware controls (e.g. a web kiosk with dedicated content), tactile cues on the hardware might be described (e.g. the arrow shaped key, the round key on the right side). This success criterion is not intended to prevent the use of tactile cues in instructions.

Specific Benefits of Success Criterion 1.3.3:

  • People who are blind and people who have low vision may not be able to understand information if it is conveyed by shape and/or location. Providing additional information other than shape and/or location will allow them to understand the information conveyed by shape and/or alone.

Examples of Success Criterion 1.3.3

Related Resources

Resources are for information purposes only, no endorsement implied.

(none currently documented)

Techniques and Failures for Success Criterion 1.3.3 - Sensory Characteristics

Each numbered item in this section represents a technique or combination of techniques that the WCAG Working Group deems sufficient for meeting this Success Criterion. [begin change]However, it is not necessary to use these particular techniques. Any techniques, whether published by the WCAG group or not, can be sufficient if a) they satisfy the Success Criterion and b) all of the WCAG 2.0 conformance requirements have been met.[end change]

Additional Techniques (Advisory) for 1.3.3

Although not required for conformance, the following additional techniques should be considered in order to make content more accessible. Not all techniques can be used or would be effective in all situations.

  • Using an image with a text alternative for graphical symbols instead of a Unicode font glyph with the desired graphical appearance but different meaning (future link)

Common Failures for SC 1.3.3

The following are common mistakes that are considered failures of Success Criterion 1.3.3 by the WCAG Working Group.