LED indicator considerations for colorblind users?

1. What color should you avoid using for individuals who are color blind?
2. What is the color red usually perceived as by users with color blindness?
3. What are the best colours to use for colour blindness?
4. What are the interface design rules for color blinds?

What color should you avoid using for individuals who are color blind?

Avoid the following color combinations, which are especially hard on color blind people: Green & Red; Green & Brown; Blue & Purple; Green & Blue; Light Green & Yellow; Blue & Grey; Green & Grey; Green & Black.

What is the color red usually perceived as by users with color blindness?

Red-green color blindness.

This is the most common form, causing trouble differentiating between red and green. Protanomaly is when red looks more like green. Deuteranomaly is when green looks more like red.

What are the best colours to use for colour blindness?

The first rule of making a palette for colorblind – avoid combining red and green. So if you're aiming to create a color blind-friendly palette try to use only two basic hues: blue and red (orange and yellow will also fit). The other colors should be made out of these two hues.

What are the interface design rules for color blinds?

Two simple rules about contrast and color

First, good contrast helps a lot. The more contrast, the better the colorblind can see the difference between the two items. Second, never use color alone to convey information or indicate action. Always provide alternatives in the form of text, icons, or other indicators.