Color

Hardware Self Contained, Closed Products checkpoint 3.1

Use color as an enhancement, not as the only way to convey information or distinguish keys, controls and labels.

Rationale

If the hardware conveys information by color alone, users who cannot identify or distinguish colors will not be able to make use of the information.

Development techniques

The following techniques are the minimum required to meet Checkpoint 3.1 from the IBM Hardware Self Contained, Closed Products Accessibility Checklist:

Make color cues redundant with other cues by supplementing color coding with text, shape or relative position coding.
Color should not be used as the only way to indicate an action, prompt a response or distinguish a visual element.

The techniques above are required; the following technique is recommended to enhance accessibility.

To ensure that a color blind user will not miss any important information,use colors that vary in intensity (have sufficient brightness contrast). Lighthouse International provides guidelines for effective color contrast on their Web site at http://www.lighthouse.org/color_contrast.htm (link resides outside of ibm.com).

Testing techniques

Test the hardware to ensure that it complies with accessibility requirements.

Tools

No tools are needed to test this checkpoint:

Techniques

*One or more of the following techniques are required to verify this checkpoint:*
Action	Result
1. Verify that colors cues are redundant. Visually inspect that color provides redundant information.	Pass: Color is not the sole means of identifying keys, controls or labels. Fail: Color is the only means of identifying keys, controls or labels.
2. Verify that color is not the sole means of indicating actions or distinguishing an element. Visually inspect that color provides redundant information.	Pass: Color is not the sole means of indicating an action, and Color is not the sole means of distinguishing a visual element. Fail: Color is the sole means of indicating an action, or Color is the sole means of distinguishing a visual element.

Last updated January 31, 2008.

Checklist