Overview of Use of Color

Purpose

This requirement goes deeper than Success Criteria 1.3.3 Sensory Characteristics to focus on the use of color.

Using color alone to convey information affects people who are blind or low vision, as well as people with CVD. “Color Blind” is the common term for Color Vision Deficiency (CVD). Colorblindness affects 1 in 12 men, and 1 in 200 women. Red/green colorblindness is the most common.

How to Test

Best Practices

Use color to augment descriptions

Color can help some people to quickly gain understanding, it just needs to be used in addition to, rather than in isolation.

Here is an example of what to strive for. The Air Quality Index Chart has a description of the Air Quality Index Levels of Health Concern as well as a color level. Using color in this way is okay, because it augments the already-accessible text descriptions.

Air quality index chart uses color and text to convey information

Another example is on Wikipedia page listing current members of the Maryland senate shows Democratic or Republican Party affiliation with labels AND color.

Maryland senators are identified by color and text to indicate their respective party affiliations

A final example looks at using color and shapes together in graphs. This example is of the Cuyahoga Community College site page.

Percent Change Over Time graph - contains a red line plotted with squares, a blue line plotted with diamonds, and a green line plotted with triangles

Exceptions

None

References

Understanding Success Criterion 1.4.1: Use of Color

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