CAN/ULC-S609-M89

These requirements cover the design and construction of Type L Vents which are intended for the venting of flue gases having temperatures not exceeding 300 degrees C, from fuel-burning appliances certified for use with Type L Vents. They may also be used where Type B gas vents are used. They are intended for installation in buildings to provide an essentially vertical conduit or passageway for conveying flue gases to the outer air from the above described class of appliances.