Patent ID: 6161564
Filing Date: 2000-12-19
Classification: A62C,F16K,Y10T

Abstract:
In a drainage system for a structure with a penetration through a floor, wherein the system prevents transmission of a fire and smoke through and above the floor, the improvement which comprises:(a) a coupling having opposed ends and mounted through the penetration in the floor and secured to the floor to provide an airtight connection between the floor and the coupling;(b) a first pipe section mounted in one of the ends of the coupling adjacent an underside of the floor and connected to an outlet pipe for the drainage system;(c) a second pipe section mounted in the other one of the ends of the coupling adjacent a top side of the floor connected to a drain of a fixture, and having a first branch pipe trap between the coupling and the fixture for holding water, wherein the first branch pipe trap is at an elevation above all other branch pipe traps connected to the second pipe section; and(d) an air vent mounted at a high point of the second pipe section between the coupling and the first branch pipe trap and mounted at least four inches above a weir water level of the first branch pipe trap, wherein the air vent opens and allows air into the drainage system when a negative pressure relative to atmospheric pressure is present in the system and automatically closes when there is a positive pressure relative to atmospheric pressure present in the system and wherein the system prevents fire transmission through the penetration and floor by automatic closing of the air vent.