Abstract: The invention relates to a device for preventing communication through pipe lines of high security institutions. A flapper valve is provided with a valve seat having a plurality of teeth extending into the center of the opening formed in the valve seat. A pivotal flapper opens or closes the valve by abutting a seating face of the valve seat or moving away, under the force of a fluid flow, and allowing passage of waste water from a plumbing fixture to the main waste conduit. A water trap seal is optionally and/or separately mounted for delivering an additional amount of water into the conventional waste trap to fill in the waste trap with fluid and prevent undesirable communication. An independent conduit connected to a water supply deilvers water to a reservoir which is fluidly connected with a conventional jet conduit of a waster system upstream from an outlet point of the jet conduit into the main waste trap.

Abstract: The invention relates to a device for preventing communication through pipe lines of high security institutions. A flapper valve is provided with a valve seat having a plurality of teeth extending into the center of the opening formed in the valve seat. A pivotal flapper opens or closes the valve by abutting a seating face of the valve seat or moving away, under the force of a fluid flow, and allowing passage of waste water from a plumbing fixture to the main waste conduit. A water trap seal is optionally and/or separately mounted for delivering an additional amount of water into the conventional waste trap to fill in the waste trap with fluid and prevent undesirable communication. An independent conduit connected to a water supply delivers water to a reservoir which is fluidly connected with a conventional jet conduit of a waste water system upstream from an outlet point of the jet conduit into the main waste trap.