In our web application there's a view where we display the stress on a hardware component.
This will be displayed with a percentage value in different colour codes combined with an icon where 100% is the expected stress rate of the component.
If the stress is <=100% the text should be green with a icon in front of it.
If the stress is >150% the text would be red with a icon in front of it.
The question is now what icon I can use for communicating a value between those values, that is 100% < X <= 150%.
It should convey an alert but of a lower grade. The text will be coloured GoldenRod so an icon in the same colour scheme would be something I'm after. I want the icon to have a differing form from the other two, so maybe something inside a square as depicted in the splash of colour above.
However I don't know that symbol to use inside it. I feel as using a exclamation mark could be confusing as it's already used in the High Alert icon.
I do realize that the use of icons combined with text is a debatable issue but the icon would be there as a substitute for users having problems differentiating between colours and thereby not gaining anything from Text Colour Coding.
Does anyone have a good idea for the icon or symbol to communicate this grade of alert? Or has anyone seen an example of how grades of alert has been communicated in other instances?