Hello All, I am helping a friend with his Pizzeria I used to own a small pizza restaurant in Houston. My friends issue is smoke. The ovens I had vented outside so it was no issue. His is an in room conveyor style. It cooks real fast and good, but now and then he gets a smoke issue. Any suggestions on good Commercial kitchen air purification equipment? Hopefully something made in the USA. Anyone had a good experience they can share?