Smoke leakage (S): Failure of this criterion shall have happened if the stream amount in duct A through the take a look at exceeds 10 m³ / (m² h), connected to 20 °C and 1013 mbar, connected to The inner surface area location in the duct In the furnace. FastWrap https://fireratedinsulationforduc57788.mdkblog.com/42869021/fire-rated-insulation-for-ductworth-an-overview