Federal and California Truncated Domes Regulations—What's the Difference?
These days, the only essential difference between federal regulations and California regulations for truncated domes is this: California requires a minimum 3-foot depth in the dominant direction of travel. California also requires that truncated domes installed on state-owned public access properties be yellow in color. However, the "contrast rule" of the ADA and federal guidelines, will override this. That contrast rule requires ADA truncated domes or pads to contrast in color with the surrounding surface on which they are mounted. And that makes sense; installing yellow truncated domes tiles on a yellow-painted concrete surface would make them virtually invisible.