Your design really hammers home the idea of "stamp of approval" however it almost looks like a Nuclear warning sign. Needs to soften up quite a bit, add some color and make the little have moons around the ECO turn into leaves or something that has a "greener" connotation. We are putting it back out there because we feel with some tweeking that you have a good basic platform.
Instead of the Star that sounds ECO what about something else like a house. Combine elements of yours and of the one we have ranked #1. Think: HOUSE / STAMP OF APPROVAL / GREEN / WATER / AIR
#41, bolder Certified Eco, thinner house/more character to house, little too industrial but on the right path. Need more color please. Blue/Water, Yellow/Sun etc... Great work!!
Try something besides a checkmark (blue earth maybe with check mark in it????)