ANSI/AWWA C111/A21.11-23 (Revision of ANSI/AWWA C111/A21.
11-17)
eal crop marks
Rubber-Gasket
Joints for Ductile-
Iron Pressure Pipe
and Fittings
Effective date: Aug. 1, 2023.
First edition approved by Board of Directors July 16, 1953.
This edition approved March 13, 2023.
Approved by American National Standards Institute May 11, 2023.
SM
Since 1881
AWWA Standard
This document is an American Water Works Association (AWWA) standard. It is not a specification. AWWA standards describe
minimum requirements and do not contain all of the engineering and administrative information normally contained in
specifications. The AWWA standards usually contain options that must be evaluated by the user of the standard. Until each
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applicable law, regulation, or code of any governmental authority. AWWA standards are intended to represent a consensus
of the water industry that the product described will provide satisfactory service. When AWWA revises or withdraws this
standard, an official notice of action will be placed in the Official Notice section of Journal AWWA. The action becomes
effective on the first day of the month following the month of Journal AWWA publication of the official notice.
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ISBN-13, print: 978-1-64717-139-1 ISBN-13, electronic: 978-1-61300-670-2
DOI: http://dx.doi.org/10.12999/AWWA.C111.23
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Copyright © 2023 by American Water Works Association
Printed in USA
ii
Committee Personnel
Subcommittee 2, Joints for Pipe and Fittings, which reviewed and developed this standard, had
the following personnel at the time:
David Hughes, Chair
General Interest Members
J.A. Hrdlicka (liaison, nonvoting), Standards Engineer Liaison, AWWA, Denver, Colo.
P.A. Selig, Consultant, Birmingham, Ala.
Producer Members
W. Biery, Victaulic, Center Valley, Pa.
M. Bowsher, Star Pipe Products, Inc., Houston, Tex.
L.R. Dunn (alternate), U.S. Pipe & Foundry Company, Birmingham, Ala.
J.H. Eddings, McWane Inc., Birmingham, Ala.
J.A. Fancher (alternate), American Cast Iron Pipe Company, Birmingham, Ala.
M.D. Gaston, American Cast Iron Pipe Company, Birmingham, Ala.
D.A. Hughes, U.S. Pipe & Foundry Company, Birmingham, Ala.
K.J. Kempf (alternate), Kempf Holdings LLC Dba Foundry Services Co., Omaha, Neb.
H. Kennedy Jr., Harold Kennedy & Associates, Fuquay Varina, N.C.
J. Phillips (alternate), Star Pipe Products, Inc., Vancouver, B.C.
H.P. Tinney, Birmingham Fastener Manufacturing, Birmingham, Ala.
User Members
D.D. Montgomery, Independence Water Department, Independence, Mo.
J.M. Ross, Denver Water, Denver, Colo.
R.L. Worden, COMCD, Norman, Okla.
iii
AWWA Standards Committee A21, Ductile Iron Pipe and Fittings, which reviewed and
approved this standard, had the following personnel at the time of approval:
John R. Plattsmier, Chair
Maury D. Gaston, Vice-Chair
General Interest Members
M. Dunn, Crist Engineers, Inc., Little Rock, Ark.
J. Hebenstreit, Underwriters Laboratories Inc., Northbrook, Ill.
M.B. Horsley, Horsley Engineering LLC, Overland Park, Kans.
J.A. Hrdlicka (liaison, nonvoting), Standards Engineer Liaison, AWWA, Denver, Colo.
D.H. Kroon, Aegion, Houston, Tex.
D.D. Lary (alternate), Wright-Pierce, Topsham, Maine
C.R. Laucamp, AECOM, Chicago, Ill.
P.J. Mourt, HDR, Plymouth Meeting, Pa.
J.R. Plattsmier, Consultant, New Port Richey, Fla.
S. Pool (alternate), HDR Engineering, Denver, Colo.
T.M. Stinson, Kleinfelder SEA Company, Holbrook, Mass.
Producer Members
L.R. Dunn (alternate), US Pipe & Foundry Company, Birmingham, Ala.
J.H. Eddings, McWane Inc., Phillipsburg, N.J.
J.A. Fancher (alternate), American Cast Iron Pipe Company, Birmingham, Ala.
M.D. Gaston, American Cast Iron Pipe Company, Birmingham, Ala.
L.G. Horn, Ductile Iron Pipe Research Association, Birmingham, Ala.
D. Hughes, US Pipe & Foundry Company, Birmingham, Ala.
J.C. Jones, Georg Fischer, Dallas, Tex.
H. Kennedy, Jr., Harold Kennedy & Associates, Fuquay Varina, N.C.
J.S. Palombo, Everett J. Prescott, Inc., Gardiner, Maine
A. Rich (alternate), G.A. Rich and Sons, Deer Creek, Ill.
D. Swalley, Electrosteel, Birmingham, Ala.
M.A. Vess (alternate), Tyler Union, Anniston, Ala.
iv
User Members
M.J. Britch, Tualatin Valley Water District, Beaverton, Ore.
J. Fox, Tampa Bay Water, Clearwater, Fla.
D.D. Montgomery, Independence Water Department, Independence, Mo.
C.J. Patla, Connecticut Water Service Inc., Clinton, Conn.
G. Ramon (liaison, nonvoting), Standards Council Liaison, Little Rock Water Reclamation
Authority, Little Rock, Ark.
J.M. Ross, Denver Water, Denver, Colo.
P.A. Shively, City of Kansas City, Kansas City, Mo.
J.R. Waugh, Bureau of Reclamation, Denver, Colo.
J.T. Wilson, Cobb County–Marietta Water Authority, Marietta, Ga.
R.L. Worden, COMCD, Norman, Okla.
v
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Contents
All AWWA standards follow the general format indicated subsequently. Some variations from this
format may be found in a particular standard.
SEC. PAGE SEC. PAGE
Foreword 4.4 Special Requirements for the
Mechanical Joint........................ 6
I Introduction..................................... ix
4.5 Special Requirements for the Push-
I.A Background...................................... ix on Joint...................................... 16
I.B History............................................. ix 4.6 Special Requirements for the
I.C Acceptance....................................... xiii Flanged Joint.............................. 18
II Special Issues.................................... xiv 4.7 Performance Requirements............... 20
II.A Advisory Information on Product 5 Verification
Application................................ xiv
5.1 Inspection........................................ 21
II.B Chlorine and Chloramine
5.2 Certification and Test Records.......... 21
Degradation of Elastomers......... xv
5.3 Basis for Rejection............................ 22
III Use of This Standard....................... xv
III.A Purchaser Options and 6 Delivery
Alternatives................................ xvi 6.1 Marking........................................... 22
III.B Modification to Standard................. xvi 6.2 Packing............................................ 23
IV Major Revisions................................ xvi 6.3 Affidavit of Compliance................... 23
V Comments....................................... xvi
Appendixes
Standard A Mechanical-Joint Bolts, Gaskets,
and Installation.......................... 25
1 General
B Push-on Joint Design, Gaskets,
1.1 Scope............................................... 1 Lubricant, and Installation......... 29
1.2 Purpose............................................ 2 C Flanged-Joint Bolts, Gaskets,
1.3 Application....................................... 2 and Installation.......................... 33
D Effects of Chloramines on
2 References....................................... 2 Ductile-Iron Pipe Gaskets
and Elastomers........................... 37
3 Definitions...................................... 3
4 Requirements Figures
4.1 Materials.......................................... 5 1 Mechanical-Joint Dimensions for
4.2 Permeation....................................... 5 Sizes 3–64 in.............................. 7
4.3 General Requirements...................... 5 2 Mechanical-Joint Gasket, 3–64 in.... 12
vii
SEC. PAGE SEC. PAGE
3 Standard Design for High-Strength, 5 Standard Design for High-Strength,
Low-Alloy Steel Tee-Head Bolts Low-Alloy Steel Tee-Head Bolt
and Nuts.................................... 14 and Nut Dimensions—Inches.... 15
4 Flange Details (see Table 9).............. 19 6 Minimum Characteristic Values for
A.1 Mechanical-Joint Assembly.............. 26 Steel Tee-Head Bolts................... 15
B.1 Push-on Joint Assembly.................... 31 7 Minimum Proof Test for Tee-Head
Bolts and Nuts........................... 16
Tables 8 Required Properties and Methods of
Testing for SBR Push-on Joint
1 Properties for Gray-Iron Glands....... 6 Gaskets....................................... 17
2 Mechanical-Joint Dimensions— 9 Flange Details................................... 18
Inches........................................ 8 10 Minimum Working Pressure Ratings
3 Mechanical-Joint Gasket for Mechanical and Push-on
Dimensions, 3–64 in.................. 13 Joints.......................................... 20
4 Required Properties and Methods A.1 Mechanical-Joint Bolt Torque
of Testing for SBR Mechanical- Loads......................................... 27
Joint Gaskets.............................. 13 C.1 Flange Gasket Details....................... 34
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Foreword
This foreword is for information only and is not a part of ANSI*/AWWA C111/A21.11.
I. Introduction.
I.A. Background. Cast-iron pipe was originally made with flanged joints,
using lead gaskets. Improved joints of this type are still used for many aboveground
plant installations and other specialized applications.
The bell-and-spigot joint was developed in 1785 and extensively used until the
1950s. This joint was assembled by caulking yarn or braided hemp into the base of
the annular bell cavity and then pouring molten lead into the remaining space inside
the bell. Upon solidification, the lead was compacted by caulking, thus effecting a
watertight seal. Materials other than lead have also been used to confine yarn or hemp
in the base of the bell cavity.
The mechanical joint was developed for gas industry use in the late 1920s but
has since been used extensively in the water industry. This joint has standardized
dimensions and uses the basic principle of the stuffing box and gland, with a rubber
gasket being compressed by the gland.
The roll-on joint was developed in 1937 and was used for approximately 20 years
before its manufacture was discontinued. Assembly of this joint involved a compressed
rubber gasket rolled under a restriction ring, followed by caulked square braided jute.
The remainder of the joint was packed with a bituminous compound.
The push-on joint was developed in 1956 and represented an important
advancement in the water distribution field. This joint consists of a single rubber
gasket placed in a groove inside the socket at the bell end of the pipe. After the joint
is lubricated in accordance with the manufacturer’s instructions, the plain end of the
pipe is pushed through the gasket, compressing it and forming a pressure-tight seal.
Assembly of the push-on joint is simple and fast. Large bell holes are not required for
this joint, and it can be assembled under wet-trench conditions or even underwater.
Several special joints are available. These joints include ball and socket for submarine
or stream crossings, plain-end coupled, threaded and coupled, and other variations of
restrained joints.
I.B. History. American National Standards Committee A21 on Cast-Iron
Pipe and Fittings was organized in 1926 under the sponsorship of the American Gas
* American National Standards Institute, 25 West 43rd Street, Fourth Floor, New York, NY 10036.
ix
Association (AGA), the American Society for Testing and Materials (ASTM), AWWA,
and the New England Water Works Association (NEWWA). Between 1972 and
1984, the cosecretariats were AGA, AWWA, and NEWWA, with AWWA serving as
administrative secretariat. In 1984, the committee became an AWWA committee titled
“AWWA Standards Committee A21 on Ductile-Iron Pipe and Fittings.”
The present scope of Committee A21 activity is to develop standards and manuals
that address ductile-iron pressure pipe for water supply service and ductile-iron and
gray-iron fittings for use with this pipe. These standards and manuals include design,
dimensions, materials, coatings, linings, joints, accessories, and methods of inspection
and testing.
The work of Committee A21 is conducted by subcommittees. The scope of
Subcommittee 2, Joints for Pipe and Fittings, is to examine present A21 standards that
describe joints for ductile-iron pressure pipe and ductile-iron and gray-iron fittings to
determine what is needed to bring them up to date. These examinations should include
related matters concerning joints for ductile-iron pressure pipe and ductile-iron and
gray-iron fittings.
ANSI/AWWA C111/A21.11 was initially approved on July 16, 1953. The standard
was subsequently reviewed, revised, and reissued in 1964, 1972, 1980, 1985, 1990,
1995, 2000, 2007, and 2017. This eleventh edition was approved by the AWWA Board
of Directors on March 13, 2023.
During 1979, Committee A21 reached an agreement on a proposed new
requirement for the marking of bolts and nuts that was generally acceptable to the bolt
manufacturing industry. The significance of this change and other considerations led
to approval of the 1980 revision.
The major changes in the 1980 edition were:
1. inclusion of metric conversions;
2. inclusion of reduced ductile-iron mechanical-joint pipe bell thicknesses that
are compatible with pipe barrel thicknesses;
3. inclusion of tee-head bolts with reduced shank diameters that are properly
sized to accept rolled threads;
4. minimum elongation increased to 5 percent for ductile-iron glands;
5. deletion of the 2-in. and 2½-in. sizes; and
6. marking requirements for the tee-head bolts and nuts.
A 1984 addendum was issued to increase the thread length on ⅝-in. × 3-in. and
¾-in. × 3½-in. tee-head bolts by ¼ in. and to permit polygon-shaped bells on fittings.
x
The major revisions in the 1985 edition included:
1. addition of Sec. 11-1.3, Modifications to Push-on and Mechanical Joints;
2. revision of Sec. 11-2.5 defining the manufacturer as the party that produces
joints according to this standard;
3. addition of Sec. 11-2.7 defining the owner;
4. revision of Sec. 11-8.1 to permit the use of either ductile-iron or gray-iron
glands unless otherwise specified by the purchaser;
5. addition of Note 8 under Figure 11.1 to permit ductile-iron glands with
reduced flange thicknesses between the bolt holes;
6. revision of Sec. 11-7.4.1 and Sec. 11-8.3.1 to delete natural rubber as a
gasket material; and
7. revision of Sec. 11-9, Performance Requirements, to cover both push-on
joints and modified mechanical joints.
The major revisions in the 1990 edition of this standard were as follows.
1. A section on permeation was added and designated as Sec. 11-4. The
previous Sec. 11-4, General Requirements, was changed to Sec. 11-5, and subsequent
sections were changed accordingly.
2. Sec. 11-5.2 was revised to include flanged joints.
3. Sec. 11-8.1 was revised to require cast markings identifying the country
where cast.
4. Sec. 11-8.4.1 and Sec. 11-9.3.1 were revised to identify styrene butadiene
rubber (SBR) as the standard material for gaskets and to indicate the availability of
other elastomers for special service applications. These sections were also revised to
require molding or permanently marking the name of the country where molded on
the gasket.
5. Tables 11.3 and 11.4 and Figures 11.3 and 11.4 were revised to adjust the
thread length on the bolts. Also, the method of dimensioning the bolt thread length
was revised.
6. Appendix B, Metric Dimensions, was eliminated, along with tables and
figures exclusively for metric measure. Metric conversion formulas were added in notes
to tables and figures for direct conversion of US customary units.
7. Appendix B, Flanged-Joint Bolts, Gaskets, and Installation, was added to
include flanged joints.
The major revisions in the 1995 edition of this standard were as follows.
1. The acceptance clause (Sec. I.C) was revised to approved wording.
xi
2. A statement that addresses physical requirements of elastomers other than
SBR was added to Sec. 4.3.4.1.
3. A statement was added to Sec. 4.2.2 allowing flange joints in 12-in. and
smaller sizes to be rated for 350 psi with the use of special gaskets, the rating of which
is supported by performance testing as described in Sec. 4.5.
4. Sec. 1.1, Figure 1, and Table 2 were revised to delete mechanical-joint pipe
larger than 24 in.
5. A plus tolerance was added to the bell flange thickness (L) for pipe and C110
fittings and added to the dimensions across the centerlines of the bolt holes (K1 and
K2) in Table 2.
6. Dimensions were added to Table 2 for ANSI/AWWA C153/A21.53 fittings
for 18–24-in. sizes.
7. Figures 11.3 and 11.4 and Tables 11.3 and 11.4 from the previous revision
were combined into Figure 3 and Table 5, respectively.
8. Sec. 4.3.5, Sec. A.1, and Sec. B.1 were revised to require compliance of
fasteners to Public Law 101-592, the “Fastener Quality Act.”
9. Dimensional data were added to Table B.1 for 60- and 64-in. flange gaskets.
There were no major changes in the 2000 edition.
The major revisions to the 2007 edition were as follows:
1. added requirement for materials to comply with the Safe Drinking Water
Act and other federal requirements to Sec. 4.1;
2. added requirement for joints to withstand the combined working pressure
and surge allowance specified in pipe or fitting standards to Sec. 4.3.2;
3. in Table 2, added plus tolerance to K1 dimension for fitting sizes 3–24 in.
for ANSI/AWWA C153 compact fittings; deleted note allowing 350-psi
(2.41-MPa) rating with special gaskets; added bolt length information for
pipe and ANSI/AWWA C153 compact fittings; added L dimension for
ANSI/AWWA C153 compact fittings sizes 30–48 in.; and deleted note
requiring N dimension conformance for glands;
4. added Sec. 4.6, Special Requirements for the Flanged Joint; and
5. added requirement for design qualification of major modifications for
mechanical and push-on joints that have been in service for less than 10 years
and a requirement to retain the testing records for 10 years to Sec. 4.7.1.
The major revisions to the 2012 edition of this standard were as follows.
1. The scope of the standard was revised and other applicable sections
throughout the standard were updated to include wastewater and reclaimed water.
xii
2. A new section, Sec. 4.1.2, Certification, was added to include a requirement
for NSF†/ANSI/CAN‡ 61 certification on products if they will be in contact with
potable water.
3. Tables 4 and 8: Deleted reference to ASTM D572, Standard Test Method
for Rubber Deterioration by Heat and Oxygen, and added reference to ASTM D573,
Standard Test Method for Rubber—Deterioration in an Air Oven. Modified minimum
aging requirements to reflect revised test method.
I.C. Acceptance. In May 1985, the US Environmental Protection Agency
(USEPA) entered into a cooperative agreement with a consortium led by NSF
International (NSF) to develop voluntary third-party consensus standards and a
certification program for direct and indirect drinking water additives. Other members of
the original consortium included the Water Research Foundation (formerly AwwaRF)
and the Conference of State Health and Environmental Managers (COSHEM).
AWWA and the Association of State Drinking Water Administrators (ASDWA) joined
later.
In the United States, authority to regulate products for use in, or in contact with,
drinking water rests with individual states.§ Local agencies may choose to impose
requirements more stringent than those required by the state. To evaluate the health
effects of products and drinking water additives from such products, state and local
agencies may use various references, including
1. Specific policies of the state or local agency.
2. Two standards developed under the direction of NSF: NSF/ANSI/CAN 60,
Drinking Water Treatment Chemicals—Health Effects, and NSF/ANSI/CAN 61,
Drinking Water System Components—Health Effects.
3. Other references, including AWWA standards, Food Chemicals Codex, Water
Chemicals Codex,¶ and other standards considered appropriate by the state or local
agency.
Various certification organizations may be involved in certifying products in
accordance with NSF/ANSI/CAN 61. Individual states or local agencies have authority
to accept or accredit certification organizations within their jurisdictions. Accreditation
of certification organizations may vary from jurisdiction to jurisdiction.
†
NSF International, 789 North Dixboro Road, Ann Arbor, MI 48105.
‡
Standards Council of Canada, 55 Metcalfe Street, Suite 600, Ottawa, ON K1P 6L5 Canada.
§
Persons outside the United States should contact the appropriate authority having jurisdiction.
¶
Both publications available from National Academy of Sciences, 500 Fifth Street, NW, Washington,
DC 20001.
xiii
Annex A, “Toxicology Review and Evaluation Procedures,” to NSF/ANSI/CAN 61
does not stipulate a maximum allowable level (MAL) of a contaminant for substances
not regulated by a USEPA final maximum contaminant level (MCL). The MALs of an
unspecified list of “unregulated contaminants” are based on toxicity testing guidelines
(noncarcinogens) and risk characterization methodology (carcinogens). Use of Annex
A procedures may not always be identical, depending on the certifier.
ANSI/AWWA C111 does not address additives requirements. Users of this standard
should consult the appropriate state or local agency having jurisdiction in order to
1. determine additives requirements, including applicable standards.
2. determine the status of certifications by parties offering to certify products
for contact with, or treatment of, drinking water.
3. determine current information on product certification.
II. Special Issues.
II.A. Advisory Information on Product Application. The following special service
requirements should be noted:
1. Sec. 4.4.3 provides for tapped holes in the bells of mechanical joints for stud
bolts. This option is intended for use when headed bolts or slotted holes will not suffice
(e.g., when the bell is to be embedded in a concrete wall).
2. Although this standard does not stipulate orientation of bolt holes in the
flanges of the mechanical joint, at times it is convenient or necessary to have the bolt
holes oriented. The normal, but not universal, practice is to have bolt holes straddle
the vertical centerline of the fitting, valve, and hydrant. (The vertical centerline of a
fitting is determined when the fitting is in the position to change the direction of the
fluid flowing in a horizontal plane. With standard base bends and standard base tees,
the vertical centerline is determined when the fitting is in a position to change the
direction of the fluid flowing in a vertical plane.) If orientation is necessary, it should
be stated on the purchase order.
Note: Push-on joints for ductile-iron pipe and ductile-iron and gray-iron fittings
are designed so that negative pressure cannot pull the gasket into the pipe. Testing has
been performed to confirm this design parameter for joint-sealing capability under the
condition of negative pressure within the pipe.
3. Attention is directed to an apparent conflict among ANSI/AWWA
C110/A21.10, ANSI/AWWA C115/A21.15, and ASME B16.1 with regard to pressure
ratings for flanges.
xiv
In ANSI/AWWA C110/A21.10, flanged fittings are rated for 150 psi or 250 psi*
(1.03 MPa or 1.72 MPa) working pressure depending on the material (gray iron or ductile
iron) and the size of the fitting. Flanges provided according to ANSI/AWWA C115/
A21.15 are rated for water service of 250 psi* (1.72 MPa) or greater working pressure.
ANSI/AWWA C110/A21.10 and ANSI/AWWA C115/A21.15 flanges, which are
adequate for water service of 250 psi* (1.72 MPa) or greater working pressure, have
bolt circles and bolt holes identical to Class 125 ASME B16.1 flanges, and also match
Class 125 ASME B16.1 flanges for service temperatures of –20 to 150°F (–28.9 to
65.6°C). These flanges are rated only for 150–200 psi (1.03–1.38 MPa), depending on
the flange size, class or grade of iron, and fluid temperature.
ASME B16.1 also contains the details of a Class 250 flange that is heavier, has
a raised face and a larger bolt circle, and uses larger-sized bolts than the Class 125
ASME B16.1 flange and the flanges specified in ANSI/AWWA C115/A21.15 and
ANSI/AWWA C110/A21.10. This Class 250 ASME B16.1 flange will not match
the Class 125 ASME B16.1 flange or ANSI/AWWA C115/A21.15 and ANSI/
AWWA C110/A21.10 flanges.
II.B. Chlorine and Chloramine Degradation of Elastomers. The selection
of materials is critical for water service and distribution piping in locations where
there is a possibility that elastomers will be in contact with chlorine or chloramines.
Documented research has shown that elastomers such as gaskets, seals, valve seats, and
encapsulations may be degraded when exposed to chlorine or chloramines. The impact
of degradation is a function of the type of elastomeric material, chemical concentration,
contact surface area, elastomer cross section, and environmental conditions, as well as
temperature. Careful selection of and specifications for elastomeric materials and the
specifics of their application for each water system component should be considered to
provide long-term usefulness and minimum degradation (swelling, loss of elasticity, or
softening) of the elastomer specified.
III. Use of This Standard. It is the responsibility of the user of an AWWA
standard to determine that the products described in that standard are suitable for use
in the particular application being considered. To ensure product compliance with
standard requirements, third- party certifying bodies such as Underwriters Laboratories
may be used.
* Some sizes may be rated for 350 psi (2.41 MPa) with the use of special gaskets.
xv
III.A. Purchaser Options and Alternatives. The following information should be
provided by the purchaser.
1. Standard used—that is, ANSI/AWWA C111/A21.11, Rubber-Gasket Joints
for Ductile-Iron Pressure Pipe and Fittings, of latest revision.
2. Details of federal, state, provincial, territorial, and local requirements
(Sec. 4.1).
3. For applications other than potable water, whether compliance with NSF/
ANSI/CAN 61, Drinking Water System Components—Health Effects, is required
(Sec. 4.1.2).
4. Mechanical-joint, flanged-joint, and push-on joint pipe and fittings may
generally be purchased with or without joint accessories (Sec. 4.3.4).
5. Special requirements for the mechanical joint (Sec. 4.4).
6. Special elastomer gaskets, if required for wastewater, reclaimed water, or
other special service applications (Sec. 4.4.4).
7. Purchaser must request drawings of the joint and gasket, if desired
(Sec. 4.5.1).
8. Special flange bolt-hole orientations, if required (Sec. 4.6.3.2).
9. Inspection (Sec. 5.1.1).
10. Certification and test records (Sec. 5.2).
11. Information on bolts and nuts, if required (Sec. 6.1.2).
III.B. Modification to Standard. Any modification of the provisions, definitions,
or terminology in this standard must be provided by the purchaser.
IV. Major Revisions. The major revisions in this edition of this standard are
as follows:
1. language added to be consistent with AWWA Standards Council guidelines;
2. clarification to rubber gasket material requirement in Sec. 4.4.4; and
3. clarification for torque requirements of flanged gaskets in App. C.3.
V. Comments. If you have any comments or questions about this standard,
please call AWWA Engineering and Technical Services at 303.794.7711; write to the
department at 6666 West Quincy Avenue, Denver, CO 80235-3098; or email at
standards@awwa.org.
xvi
