what is an air admittance valve
TECHNICAL SPECIFICATIONS
Engineering Specification: The intended purpose of an air admittance valve is to provide a method of allowing air to enter a plumbing system as an alternative to a vent extended outside a building to outside air and to prevent plumbing system sewer gases from entering inside a building and to protect against siphonage of a plumbing fixture trap.
Code Approvals:
International Plumbing Code (IPC)
International Residential Code (IRC)
Uniform Plumbing Code (UPC Section 301.2)
Standards Compliance:
ANSI/ASSE 1050 (stack type)
ANSI/ASSE 1051 (individual fixture & branch type)
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