Smoke leakage (S): The duct shall not Have a very leakage exceeding 5 m³/h for each one m² of internal surface area place. This shall be connected with the surface area spot in the duct from the perforated plate to the top from the duct because of the inlet nozzles. https://greasetightextractductwor68899.izrablog.com/37322942/the-single-best-strategy-to-use-for-grease-tight-extract-ductwork