I am "color blind" but its a bad name for the affliction because its not accurate description of the problem. It indicates that we see in gray scale or black and white or browns, or lots of other silly notions I've heard people say over the years. A more accurate description of what i see is a color insensitivity and trouble with contrasts. For example, and this is me... others have it worse or better than I, a red light on a bright sunny day is not noticeable. I see it as red but I don't notice it like others would. Its bad for driving so I've trained myself to consciously look for traffic lights and look for the color. Also, the color blindness tests where you see numbers inside colored dots is a good way to understand it: i don't see the numbers in the green shaded tests but i do OK with the red tests. the problem is with contrasts of colors melding together rather than standing out. Which brings us to exactly why using color codes for an alerter on a page is a bad idea. Many people will have trouble seeing the contrast between the colors, even those with mild cases will have trouble. I'd recommend that you abandon the color code system and instead use symbols or status codes. If you have a color blind operator, its only a matter of time before he misses a red alert.

jeffrey mergler