Smoke leakage (S): Failure of the criterion shall have occurred If your stream rate in duct A throughout the check exceeds 10 m³ / (m² h), relevant to twenty °C and 1013 mbar, connected with The inner surface area space of your duct In the furnace. Retrieved 10 January 2020. https://fireratedinsulationforduc45566.blogdosaga.com/36774201/the-best-side-of-fire-rated-insulation-for-ductworth