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Section 202 - General Definitions

AIR ADMITTANCE VALVE

One-way valve design to allow air to enter the plumbing drainage system when negative pressures develop in the piping system. The device shall close by gravity and seal the vent terminal at zero differential pressure (no flow conditions) and under positive internal pressures. The purpose of an air admittance valve is to provide a method of allowing air to enter the plumbing drainage system without the use of a vent extended to open air and to prevent sewer gases from escaping into a building.

Section 303 - Materials

PLASTIC PIPE, FITTINGS, AND COMPONENTS

All plastic pipe, fittings and components shall be third-party certified as conforming to NSF 14.

Section 905 - Vent Connections

905.1 - Connection

All individual, branch and circuit vents shall connect to a vent stack, stack vent, air admittance valve or extend to the open air.

Section 917 - Air Admittance Valves

917.1 General

Vent systems utilizing air admittance valves shall comply with this section. Individual-and-branch-type air admittance valves shall conform to ASSE 1051.

917.2 Installation

The valves shall be installed in accordance with the requirements of this section and the manufacturer's installation instructions. Air admittance valves shall be installed after the DWV testing required by Section 312.2 or 312.3 has been performed.

917.3

Where permitted. Individual, branch and circuit vents shall be permitted to terminate with a connection to an air admittance valve. The air admittance valve shall only vent fixtures that are on the same floor level and connect to a horizontal branch drain. The horizontal branch drain shall conform to Section 917.3 or Section 917.3.2.

917.3. 1

Location of branch. The horizontal branch drain shall connect to the drainage stack or building drain a maximum of four branch intervals from the top of the stack.

917.3.2

Relief vent. The horizontal branch shall be provided with a relief vent that shall connect to a vent stack, or stack vent, or extend outdoors to the open air. The relief vent shall connect to the horizontal branch drain between the stack air building drain and the most downstream fixture drain connected to the horizontal branch drain. The relief vent shall be sized in accordance with Section 916.2 and installed in accordance with Section 905. The relief vent shall be permitted to serve as the vent for other fixtures.

917.4

Location The air admittance valve shall be located a minimum of 4 inches 9102 mm) above the horizontal branch drain or fixture drain being vented. The air admittance valve shall be located within the maximum developed length permitted for the vent. The air admittance valve shall be installed a minimum of 6 inches (152 mm) above insulation materials.

917.5

Access and Ventilation Access shall be provided to all air admittance valves. The valve shall be located within a ventilated space that allows air to enter the valve.

917.6 - Size

The air admittance valve shall be rated in accordance with the standard for the size of the vent to which the valve is connected.


917.7 - Vent required

Within each plumbing system, a minimum of one stack vent or vent stack shall extend outdoors to the open air.

917.8 - Prohibited Installations

Air admittance valves shall not be installed in non neutralized special waste systems as descried in Chapter 8. Valves shall not be located in spaces utilized as supply or return air plenums.

“Portions of this web site / publication reproduce sections from the 2006 International Residential Code for One and Two Family Dwellings and from the 2006 International Plumbing Code, International Code Council, Inc., Falls Church, Virginia. Reproduced with permission. All Rights reserved.”

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Section P3114 - Air Admittance Valves

P3114.1 General.

Vent systems utilizing air admittance valves shall comply with this section. Individual-and-branch-type air admittance valves shall conform to ASSE 1051. Stack type air admittance valves shall conform to ASSE 1050.


3114.2 Installation.

The valves shall be installed in accordance with the requirements of this section and the manufacturer's installation instructions. Air admittance valves shall be installed after the DWV testing required by Section P2503.5.1 or P 2503.5.2 has been performed.


3114.3 Where permitted.

Individual vents, branch vents, circuit vents and stack vents shall be permitted to terminate with a connection to an air admittance valve.


3114.4 Location

Individual and branch air admittance valves shall be located a minimum of 4 inches (102 mm) above the horizontal branch drain or fixture drain being vented. Stack-type air admittance valves shall be located a minimum of 6 inches (152 mm) above the flood level rim of the highest fixture being vented. The air admittance valve shall be located within the maximum developed length permitted for the vent. The air admittance valve shall be installed a minimum of 6 inches (152 mm) above insulation materials installed in attics.


3114.5 Access and Ventilation

Access shall be provided to all air admittance valves. The valve shall be located within a ventilated space that allows air to enter the valve.


3114.6 Size

The air admittance valve shall be rated in accordance with the standard for the size of the vent to which the valve is connected.


3114.7 Vent required.

Within each plumbing system, a minimum of one stack vent or vent stack shall extend outdoors to the open air.

"Portions of this web site / publication reproduce sections from the 2006 International Residential Code for One and Two Family Dwellings and from the 2006 International Plumbing Code, International Code Council, Inc., Falls Church, Virginia. Reproduced with permission. All Rights reserved."

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Chapter 3 - General Regulations

301.2 Alternate Materials and Methods of Construction Equivalency

Nothing in this code is intended to prevent the use of systems, methods, or devices of equivalent or superior quality, strength, fire resistance, effectiveness, durability, and safety over those prescribed by this code. Technical documentation shall be submitted to the Authority Having Jurisdiction to demonstrate equivalency. The Authority Having Jurisdiction shall approve the system method or device when determined to be equivalent or superior.

However, the exercise of this discretionary approval by the Authority Having Jurisdiction shall have no effect beyond the jurisdictional boundaries of said Authority Having Jurisdiction. Any alternate material or method of construction so approved shall not be considered as conforming to the requirements and/or intent of this code for any purpose other than that granted by the Authority Having Jurisdiction when the submitted date does not prove equivalency.

301.2.1 Testing

The Authority Having Jurisdiction shall have the authority to require tests, as proof of equivalency.

301.2.1.1

Tests shall be made in accordance with approved standards, by an approved testing agency at the expense of the applicant. In the absence of such standards, the Authority Having Jurisdiction shall have the authority specify the test procedure.

301.2.1.2

The Authority Having Jurisdiction shall have the authority to require tests to be made or repeated if, at any time, there is reason to believe that any material or device no longer conforms to the requirements on which its approval was based.



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2006 NATIONAL STANDARD PLUMBING CODE (NSPC)
Appendix E - Special Design Plumbing Systems

NOTE: Following sections of the code cover the special design requirements that apply to all of the systems in Appendix E.

E.1 GENERAL REQUIREMENTS

E.1.1
Special design plumbing systems shall include all systems that vary in detail from the requirements of this Code.

E.1.2
The provisions of this Appendix shall control the design, installation, and inspection of special design plumbing systems.

E.1.3
Special design plumbing systems shall conform to the Basic Principles of this Code.

E.1.4
Special design plumbing systems shall be designed by a registered design professional who is licensed to practice in the particular jurisdiction.

E.2 Plans, Specifications, and Computations

E.2.1
Plans, specifications, computations, and other related data for special design plumbing systems, prepared by the registered design professional, shall be submitted to the Authority Having Jurisdiction for review and approval prior to installation.

E.2.2
The design plans shall indicate that the plumbing system (or portions thereof) is a special design system.

E.3 Installation of Special Design Plumbing Systems

E.3.1
Special design plumbing systems shall be installed according to established, tested and approved criteria, including manufacturer’s instructions.

E.3.2
The installation shall comply with Chapter 2 – General Regulations and other applicable requirements of this Code.

E.4 Certification of Compliance

E.4.1
Inspection shall be made by the Authority Having Jurisdiction to ensure conformance with data submitted for approval and the applicable requirements of this Code.

E.4.2
The complete installation and performance of the special design plumbing system shall be certified by the registered design professional as complying with the requirements of the special design.

E.8 Air Admittance Valves

E.8.1 - Definition

Air admittance valve: A one way valve designed to allow air to enter the plumbing drainage system when negative pressures develop in the system. The device closes by gravity, without springs or other mechanical means, and seals the vent terminal at zero differential pressure (no flow conditions) and also under positive internal pressure. The purpose of an air admittance valve are (1) to provide a method of allowing air to enter the plumbing drainage system without the need for a vent extended outdoors to open air, and (2) to prevent sewer gases from escaping into the building.


E.8.2 - Where permitted

E.8.2.1
Branch, circuit, common, continuous and individual vents shall be permitted to terminate with a connection to an individual or branch type air admittance valve complying with ASSE 1051. Individual and branch type air admittance valves shall only vent fixtures that are on the same floor level and connect to a horizontal branch drain.


E.8.2.2
Vent stacks and stack vents shall be permitted to terminate at a stack type air admittance valve complying with ASSE 1051.

EXCEPTIONS:
(1.) Vent stacks and stack vents serving drainage stacks that exceed six (6) branch intervals in height.
(2.) Vent stacks and stack vents that serve relief vents in Section E.8.3

E.8.2.3
Air admittance valves shall not be permitted in the following applications:
a. vents for special waste drainage systems (Sections 9.4.1 and 9.4.2)
b. vents for sewage pump ejector pump sites
c. vents for pneumatic sewage ejectors
d. suds pressure zone venting e. relief vents required by Section E.8.3.1


E.8.3 - Relief Vents

E.8.3.1
A relief vent shall be provided where a horizontal branch drain that is vented by one or more air admittance valves connects to a drainage stack more than four (4) branch intervals from the top of the stack. The relief vent shall connect vertically to the horizontal branch drain between the drainage stack and the most downstream fixture drain connection on the horizontal branch drain. Relief vents shall extend from the horizontal branch drain to a vent stack, or other vent that terminates outdoors in open air.


E.8.3.2
Relief vents shall be the full size of the horizontal branch drain that they serve, up to a 3" maximum required size.


E.8.4 - Installation

E.8.4.1
Air admittance valves shall be installed in accordance with the manufacturer's instructions and Section E.8.

E.8.4.2
Air admittance valves shall connect to fixture trap arms within the maximum allowable trap arm lengths in Table 12.8.1.

E.8.4.3
Individual and branch type air admittance valves shall be installed at least 4 inches above the top of the trap arm or horizontal branch drain that they serve.

E.8.4.4
Stack type air admittance valves shall be installed at least 6 inches above the flood level rim of the highest fixture served by the valve.

E.8.4.5
Air admittance valves shall be installed in accessible locations having free movement of air to enter the valve.

E.8.4.6
Air admittance valves shall not be installed in HVAC supply or return air plenums or other areas subject to other than atmospheric conditions.

E.8.4.7
Air admittance valves installed in insulated attic or ceiling spaces shall be installed in free air at least 6 inches above the insulation.

E.8.4.8
Air admittance valves shall be the same size as the vent pipe to which they are connected.

E.8.4.9
Air admittance valves shall not be installed until all required leak tests of the drainage and vent piping are successfully completed.

E.8.5 - Vent to outdoors required
In each plumbing drainage system vented by one or more air admittance valves, at least one vent shall extend outdoors to open air.

E.8.6 - Referenced Standards
E.8.6.1 ASSE 1050-2002 Stack Air Admittance Valves for Sanitary Drainage Systems
E.8.6.2 ASSE 1051-2002 Individual and Branch Type Air Admittance Valves for Plumbing Drainage Systems.

NOTE: The provisions are from the 2005 Supplement to the 2003 NSPC and from the 2006 NSPC.

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Division A

1.4.1.2 Definition
Air Admittance valve means a one-way valve designed to allow air to enter the drainage system when the pressure in the plumbing system is less than the atmospheric pressure.

(See Appendix Note A-2.2.10.16.(1) of Division B.)

Division B

2.2.10.16 Air Admittance Valves
1) Air admittance valves shall conform to ASSE 1051, “Individual and Branch Type Air Admittance Valves for Sanitary Drainage Systems.” (See Appendix A.)

2.5.9 Air Admittance Valves
(See A-2.2.10.16.(1) in Appendix A.)

2.5.9.1 Air Admittance Valve as a Vent Terminal
1) Individual vents may terminate with a connection to an air admittance valve as provided in Articles 2.5.9.2 and 2.5.9.3. (See also Sentence 2.2.10.16.(1).)

2.5.9.2 Air Admittance Valves
1) Air admittance valves shall only be used to vent
a) fixtures located in island counters,
b) fixtures that may be affected by frost closure of the vent due to local climatic conditions,
c) fixtures in one-and two-family dwellings undergoing renovation, or
d) installations where connection to a vent may not be practical.

2) Air admittance valves shall be located
a) not less than 100 mm above the horizontal branch drain or fixture drain being vented,
b) within the maximum developed length permitted for the vent, and
c) not less than 150 mm above insulation materials.

2.5.9.3 Installation Conditions
1) Air admittance valves shall not be installed in supply or return air plenums, or in locations where they may be exposed to freezing temperatures.
2) Air admittance valves shall be installed in accordance with the manufacturer’s installation instructions.
3) Air admittance valves shall be rated for the size of vent pipe to which they are connected.
4) Installed air admittance valves shall be
a) accessible, and
b) located in a space that allows for air to enter the valve
5) Every drainage system shall have one vent that terminates to the outdoors in conformance with Sentence 2.5.6.2.(1).

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