A method for preventing the spread of fire due to air through drain outlets has a pot within the drain having an expanding fire protection material which blocks the drain outlet

摘要

A surface drainage outlet (10) is connected to the drain system (9) and contains the fire protection unit (21) which allows free drainage through four support bars (28) and a diametral spring support bar (27) and the tension spring (26) is extended by fire protection material (24) which expands and blocks the drain outlet in the event of a fire causing the cap (25) to fall against the outlet flange (22) as the supports (28) melt.