If the option is there you might want to reconsider and go with a regular paint. You don't need fans everywhere bouncing air and dust on the surface. Besides, auto body pollution only accounts for .05% of all pollution of the world. These lawmakers are just clueless on how to approach legislation in regards. If you want waterborne your gun should be stainless inside and approved for waterborne, you should have fans bouncing air off the car at angles, you should have other things like tack rags that are for waterborne. Some would even say waterborne approved paint sticks but that's getting a little nerdy. The main thing is sticking to one system. You can get away with it with normal paint but the technology of waterborne from brand to brand is still in it's infancy and they're not all compatible. Me personally, when they say better for the environment, it's usually worse for what it's intended for.
I did some airport avis jobs when envirobase first came out and it was junk. We're talking a silver metallic hitting the surface and changing colors as it dries. If I wanted a colorful rainbow I'd get a bag of skittles. I'll gladly pollute the environment with quality paint for as long as possible and these tree huggers can kiss my arse.