IN.WC. {Ans: Inches of water Column, used to measure pressure}Venting System {Ans: A continuous, open passageway from the flue collar or draft hood of a fuel burning appliance to the outside atmosphere for the purpose of removing flue gasses. The same as an exhaust duct}Screening {Ans: Wire mesh installed at a dryer duct termination designed to prevent animals and birds from entering the duct}NFPA 211 {Ans: NATIONAL Fire Protections Association, Standards for chimneys, fireplaces, vents and solid fuel burning appliances}Video Scan {Ans: A system incorporating a closed circuit video camera and television or monitor for inspecting the interior of flues, ducts and other inaccessible areas}Appliance {Ans: Eqipment, usually built in standardized sizes or types, installed or connected as a unit}