HepvO is a self sealing valve designed to close the waste connection below a sanitary fixture to prevent the escape of foul sewer air into the dwelling. HepvO unlike conventional waste traps, does not rely on trapped water to create a seal. Instead, HepvO uses a self-sealing membrane which performs the same function as a water seal trap but without the risk of evaporation, siphonage, or cracking under freezing conditions. The HepvO Sanitary Waste Valve means enhanced plumbing design and system efficiency, without compromising performance or risking the escape of foul air into the living space from the drain or sewer.