Mechanical ventilation: This utilizes followers, ducts, and vents to flow into and Trade indoor and outdoor air. After the hood has been effectively sized, the cfm is calculated dependant on code criteria or UL tests. The exhaust cfm will determine the capture velocity which will adequately deal with the airstream https://beckettmnmjh.ampedpages.com/not-known-factual-statements-about-restaurant-and-bar-ventilation-56904946