Understanding SC 1.3.3: Sensory Characteristics (Level A)

In Brief

Goal

Instructions are understandable by more people.

What to do

Describe controls by name, not just by appearance or location.

Why it's important

People who are blind or have low vision need non-visual instructions.

Intent

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 instructions that are 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.

Benefits

• People who are blind and people who have low vision may not be able to understand instructions if they rely only on a description of the shape and/or location of content. Providing additional information in any instructions other than shape and/or location will allow users to understand the instructions even if they cannot perceive shape and/or location.

Examples

Example 1: Instructions for interpreting a schedule of competitive events references colored icons in different shapes to indicate the venue for each event

A table presents a list of times across the top row and a list of events in the first vertical column and instructions are provided under the table: "Events marked with a blue diamond are played on field A and events marked with a green circle are played on field B." The instructions rely on color and shape only and result in a failure of this criterion.

Example 2: An online multi-page survey

An online multi-page survey uses a link implemented as a green arrow icon placed in the lower right hand corner of the content to move from one survey page to the next. The arrow is clearly labeled with "Next" and the instructions state, "To move to the next section of the survey, select the green arrow icon labeled 'Next' in the lower right corner below the last survey question." The instruction uses positioning and color to help identify the icon; the instruction does not rely on these sensory characteristics since it also refers to the label, so it passes this criterion.

Techniques

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. A technique may go beyond the minimum requirement of the criterion. There may be other ways of meeting the criterion not covered by these techniques. For information on using other techniques, see Understanding Techniques for WCAG Success Criteria, particularly the "Other Techniques" section.

Test Rules

The following are Test Rules for certain aspects of this Success Criterion. It is not necessary to use these particular Test Rules to check for conformance with WCAG, but they are defined and approved test methods. For information on using Test Rules, see Understanding Test Rules for WCAG Success Criteria.

• Content has alternative for visual reference