Mechanical ventilation: This takes advantage of supporters, ducts, and vents to flow into and Trade indoor and outside air. Code requirements and jurisdictions have simplified the choice process by environment the cfm for every area in the hood or for each linear foot of exposed hood depending on two problems. https://remingtonzyvtp.theideasblog.com/30037066/5-simple-statements-about-restaurant-and-bar-ventilation-explained