It’s the Technology!
Air Burner = Clean Burning.
The primary purpose of the air curtain is to create a "secondary burn chamber." The air curtain acts like a lid covering the opening in a FireBox. As smoke particles rise off the fire the hot gases are trapped under the air curtain. These smoke particles are then reburned, significantly reducing the particle size to the point they are able to ascribe through the air curtain; appearing more like wave of heat than smoke. The result is a very clean burn, up to 90% cleaner than open burning with opacities well under 10% per EPA Method 9 Testing (as compared to open burning, which typically can run at 80% to 100% opacity).