USACE / NAVFAC / AFCESA / NASA UFGS-33 51 15 (November 2008)
--------------------------------
Preparing Activity: USACE Superseding
UFGS 33 51 00.00 20 (April 2006)
UFGS-33 51 03.00 10 (April 2008)
UNIFIED FACILITIES GUIDE SPECIFICATIONS
References are in agreement with UMRL dated March 2008
SECTION 33 51 15
NATURAL-GAS / LIQUID PETROLEUM GAS DISTRIBUTION
11/08
NOTE: This guide specification covers the requirements for natural or manufactured
gas distribution systems designed in accordance with ASME B31.8, or Liquified
Petroleum Gas (LPG) Distribution systems designed in accordance with NFPA 58
.
Edit this guide specification for project specific requirements by adding, deleting,
or revising text. For bracketed items, choose applicable items(s) or insert
appropriate information.
Remove information and requirements not required in respective project, whether
or not brackets are present.
Comments and suggestions on this guide specification are welcome and should
be directed to the technical proponent of the specification. A listing of technical
proponents, including their organization designation and telephone number, is
on the Internet.
Recommended changes to a UFGS should be submitted as a Criteria Change Request
(CCR).
This guide specification includes tailoring options for Liquid Petroleum Gas
(LPG) distribution piping systems. Selection or deselection of a tailoring
option (select view-tailoring options) will include or exclude that option in
the section. Specific project editing is still required for the resulting section.
PART 1 GENERAL
NOTE: This guide specification may be used for specifying liquefied petroleum
gas (LPG) if the following modifications are made:
a. Delete all references to fiberglass and add the following to paragraph "Polyethylene
Pipe, Tubing, Fittings and Joints" in PART 2: Polyethylene pipe, tubing, and
fittings are recommended by the manufacturer for use with LPG.
b. Require, where applicable, the LPG distribution system to be in accordance
with NFPA 58, Storage and Handling of Liquefied Petroleum Gases, instead of
ASME B31.8.
1.1 REFERENCES
NOTE: This paragraph is used to list the publications cited in the text of
the guide specification. The publications are referred to in the text by basic
designation only and listed in this paragraph by organization, designation,
date, and title.
Use the Reference Wizard's Check Reference feature when you add a RID outside
of the Section's Reference Article to automatically place the reference in the
Reference Article. Also use the Reference Wizard's Check Reference feature
to update the issue dates.
References not used in the text will automatically be deleted from this section
of the project specification when you choose to reconcile references in the
publish print process.
The publications listed below form a part of this specification to the extent referenced. The publications are
referred to within the text by the basic designation only.
[AMERICAN GAS ASSOCIATION (AGA)AGA B109.2(2000)Diaphragm-Type Gas Displacement Meters (500 cubic ft./hour Capacity and Over)AGA XR0603(2006) AGA Plastic Pipe Manual for Gas Service][AMERICAN PETROLEUM INSTITUTE (API)API Spec 5L(2007) Specification for Line PipeAPI Spec 6D(2008; Errata 2008; Errata 2008) Specification for Pipeline ValvesAPI Std 1104(2005; Errata 2007; Errata 2008) Welding of Pipeline and Related Facilities][AMERICAN SOCIETY OF CIVIL ENGINEERS (ASCE)ASCE 25(2008) Standard for Earthquake-Activated Automatic Gas Shutoff Devices][AMERICAN WATER WORKS ASSOCIATION (AWWA)AWWA C203(2002) Coal-Tar Protective Coatings and Linings for Steel Water Pipelines - Enamel and Tape - Hot-AppliedAWWA C213(2007) Fusion-Bonded Epoxy Coating for the Interior and Exterior of Steel Water Pipelines][ASME INTERNATIONAL (ASME)ASME B1.20.1(1983; R 2006) Pipe Threads, General Purpose (Inch)ASME B16.11(2005) Forged Fittings, Socket-Welding and ThreadedASME B16.21(2005) Nonmetallic Flat Gaskets for Pipe FlangesASME B16.34(2004) Valves - Flanged, Threaded and Welding EndASME B16.40(2002; Errata 2003) Manually Operated Thermoplastic Gas Shutoffs and Valves in Gas Distribution SystemsASME B16.5(2003) Standard for Pipe Flanges and Flanged Fittings: NPS 1/2 Through NPS 24ASME B16.9(2007) Standard for Factory-Made Wrought Steel Buttwelding FittingsASME B31.8(2007) Gas Transmission and Distribution Piping SystemsASME BPVC SEC VIII D1(2007; Addenda 2008) Boiler and Pressure Vessel Code; Section VIII, Pressure Vessels Division 1 - Basic CoverageASME PTC 25(2001) Pressure Relief Devices][ASTM INTERNATIONAL (ASTM)ASTM A 135/A 135M(2006) Standard Specification for Electric-Resistance-Welded Steel PipeASTM A 139/A 139M(2004) Standard Specification for Electric-Fusion (ARC)-Welded Steel Pipe (NPS 4 and over)ASTM A 181/A 181M(2006) Standard Specification for Carbon Steel Forgings, for General-Purpose PipingASTM A 53/A 53M(2007) Standard Specification for Pipe, Steel, Black and Hot-Dipped, Zinc-Coated, Welded and SeamlessASTM D 1598(2002; R 2008) Time-to-Failure of Plastic Pipe Under Constant Internal PressureASTM D 1599(2005) Resistance to Short-Time Hydraulic Failure Pressure of Plastic Pipe, Tubing, and FittingsASTM D 2513(2008b) Thermoplastic Gas Pressure Pipe, Tubing, and FittingsASTM D 2517(2006) Reinforced Epoxy Resin Gas Pressure Pipe and FittingsASTM D 2683(2004) Standard Specification for Socket-Type Polyethylene Fittings for Outside Diameter-Controlled Polyethylene Pipe and TubingASTM D 2774(2008) Underground Installation of Thermoplastic Pressure PipingASTM D 3261(2003) Standard Specification for Butt Heat Fusion Polyethylene (PE) Plastic Fittings for Polyethylene (PE) Plastic Pipe and TubingASTM D 3308(2006) PTFE Resin Skived TapeASTM D 3350(2008) Polyethylene Plastics Pipe and Fittings MaterialsASTM D 3839(2008) Underground Installation of "Fiberglass" (Glass-Fiber-Reinforced Thermosetting-Resin) Pipe][MANUFACTURERS STANDARDIZATION SOCIETY OF THE VALVE AND FITTINGS INDUSTRY (MSS)MSS SP-110(1996) Ball Valves Threaded, Socket-Welding, Solder Joint, Grooved and Flared EndsMSS SP-25(2008) Standard Marking System for Valves, Fittings, Flanges and UnionsMSS SP-72(1999) Standard for Ball Valves with Flanged or Butt-Welding Ends for General ServiceMSS SP-78(2005a) Cast Iron Plug Valves, Flanged and Threaded Ends][MASTER PAINTERS INSTITUTE (MPI)MPI 10(Jan 2004) Exterior Latex, Flat, MPI Gloss Level 1MPI 11(Jan 2004) Exterior Latex, Semi-Gloss, MPI Gloss Level 5MPI 119(Jan 2004) Exterior Latex, GlossMPI 9(Jan 2004) Exterior Alkyd, Gloss, MPI Gloss Level 6][NACE INTERNATIONAL (NACE)NACE RP0274(2004) High Voltage Electrical Inspection of Pipeline CoatingsNACE SP0185(2007) Extruded, Polyolefin Resin Coating Systems with Soft Adhesives for Underground or Submerged Pipe][NATIONAL FIRE PROTECTION ASSOCIATION (NFPA)NFPA 58(2007; Amendment 1 2007; Amendment 2 2007; Amendment 3 2007; Amendment 4 2008) Liquefied Petroleum Gas Code][THE SOCIETY FOR PROTECTIVE COATINGS (SSPC)SSPC Paint 25(1997; E 2004) Paint Specification No. 25Zinc Oxide, Alkyd, Linseed Oil Primer for Use Over Hand Cleaned Steel Type I and Type IISSPC SP 1(1982; E 2004) Solvent CleaningSSPC SP 3(2004; E 2004) Power Tool CleaningSSPC SP 6(7) Commercial Blast CleaningSSPC SP 7(2007) Brush-Off Blast Cleaning][U.S. NATIONAL ARCHIVES AND RECORDS ADMINISTRATION (NARA)49 CFR 192Transportation of Natural and Other Gas by Pipeline: Minimum Federal Safety Standards][UNDERWRITERS LABORATORIES (UL)UL Gas&Oil Dir(2008) Flammable and Combustible Liquids and Gases Equipment Directory]
1.2 SYSTEM DESCRIPTION
The gas distribution system includes natural gas piping and appurtenances from point of connection with existing
system, as indicated, to a point approximately [1500] [_____] mm [5] [_____] feet from the [facility] [facilities].
Section 31 10 00 CLEARING FOR CIVIL WORKS, applies to this section unless otherwise specified. Submit operation
and maintenance data in accordance with Section 01 78 23 OPERATION AND MAINTENANCE DATA, in three separate packages.
1.2.1 Gas Distribution System and Equipment Operation
Include maps showing piping layout, locations of system valves, gas line markers and cathodic protection system
test stations; step-by-step procedures for system start up, operation and shutdown (index system components and
equipment to the system maps); isolation procedures including valve operation to shutdown or isolate each section
of the system (index valves to the system maps and provide separate procedures for normal operation and emergency
shutdown if required to be different). Submit Data Package No. 4.
1.2.2 Gas Distribution System Maintenance
Include maintenance procedures and frequency for system and equipment; identification of pipe materials and manufacturer
by locations, pipe repair procedures, and jointing procedures at transitions to other piping material or material
from a different manufacturer. Submit Data Package No. 4.
1.2.3 Gas Distribution Equipment Maintenance
Include identification of valves and other equipment by materials, manufacturer, vendor identification and location;
maintenance procedures and recommended tool kits for valves and equipment; recommended repair methods (i.e.,
field repair, factory repair, or replacement) for each valve and piece of equipment; and preventive maintenance
procedures, possible failure modes and troubleshooting guide. Submit Data Package No. 3.
1.3 SUBMITTALS
NOTE: Review submittal description (SD) definitions in Section 01 33 00 SUBMITTAL
PROCEDURES and edit the following list to reflect only the submittals required
for the project. Submittals should be kept to the minimum required for adequate
quality control.
A “G” following a submittal item indicates that the submittal requires Government
approval. Some submittals are already marked with a “G”. Only delete an existing
“G” if the submittal item is not complex and can be reviewed through the Contractor’s
Quality Control system. Only add a “G” if the submittal is sufficiently important
or complex in context of the project.
For submittals requiring Government approval on Army projects, a code of up
to three characters within the submittal tags may be used following the "G"
designation to indicate the approving authority. Codes for Army projects using
the Resident Management System (RMS) are: "AE" for Architect-Engineer; "DO"
for District Office (Engineering Division or other organization in the District
Office); "AO" for Area Office; "RO" for Resident Office; and "PO" for Project
Office. Codes following the "G" typically are not used for Navy, Air Force,
and NASA projects.
Choose the first bracketed item for Navy, Air Force and NASA projects, or choose
the second bracketed item for Army projects.
Government approval is required for submittals with a "G" designation; submittals not having a "G" designation
are for [Contractor Quality Control approval.][information only. When used, a designation following the "G"
designation identifies the office that will review the submittal for the Government.] Submit the following in
accordance with Section 01 33 00 SUBMITTAL PROCEDURES:
SD-02 Shop Drawings
Pipe, Fittings, and Associated Materials
SD-03 Product Data
Materials and Equipment[; G][; G, [_____]]
Spare Parts[; G][; G, [_____]]
Pipe and Accessory Coatings[; G][; G, [_____]]
SD-05 Design Data
Connections to Existing Lines[; G][; G, [_____]]
Connection and Abandonment Plan[; G][; G, [_____]]
Jointing of Polyethylene and Fiberglass Piping[; G][; G, [_____]]
SD-06 Test Reports
Pressure and Leak Tests[; G][; G, [_____]]
Data in booklet form from all pressure tests of the distribution system.
SD-07 Certificates
Welder's training, qualifications and procedures[; G][; G, [_____]]
Utility Work
Certification from the Operating Agency/Utility Company that work for which the Utility is
responsible has been completed.
SD-10 Operation and Maintenance Data
Gas distribution system and equipment operation[; G][; G, [_____]]
Gas distribution system maintenance[; G][; G, [_____]]
Gas distribution equipment maintenance[; G][; G, [_____]]
Data packages, as specified.
1.4 QUALITY ASSURANCE
1.4.1 Qualifications
1.4.1.1 Welding General
a. Submit a certificate of Welder's training, qualifications and procedures, in conformance with API Std 1104
, for metal along with a list of names and identification symbols of performance qualified welders and
welding operators.
b. Welding and nondestructive testing procedures for pressure piping are specified in Section
43 02 00 WELDING PRESSURE PIPING.
c. Weld structural members in accordance with Section 05 05 23 WELDING, STRUCTURAL.
1.4.1.2 Jointing of Polyethylene and Fiberglass Piping
a. Join piping by performance qualified PE joiners, qualified by a person who has been trained and certified
by the manufacturer of the pipe, using manufacturer's pre-qualified joining procedures in accordance
with AGA XR0603. Inspect joints by an inspector qualified in the joining procedures being used and in
accordance with AGA XR0603. Welders training, qualifications and procedures,(metal and PE) includes
use of equipment, explanation of the procedure, and successfully making joints which pass tests specified
in AGA XR0603.
b. Submit a certificate of qualified jointing procedures, training procedures, qualifications of trainer,
and training test results for joiners and inspectors. Notify the Contracting Officer at least [24] [_____]
hours in advance of the date to qualify joiners and inspectors.
1.4.2 Pre-Installation Conference
1.4.2.1 Shop Drawings
Submit shop drawings, within [30] [_____]days of contract award, containing complete schematic and piping diagrams
and any other details required to demonstrate that the system has been coordinated and will properly function
as a unit. Show on the drawings proposed layout and anchorage of the system and appurtenances, and equipment
relationship to other parts of the work including clearances for maintenance and operation.
1.4.2.2 Connecting and Abandonment Plan
Submit written notification of the method and schedule for making connections to existing gas lines, to the Contracting
Officer at least 10 days in advance. Include gas line tie in, hot taps, abandonment/removal or demolition, purging,
and plugging as applicable in conformance with ASME B31.8 Include in submittal [connections to existing lines
][connection and abandonment plan].
1.5 DELIVERY, STORAGE, AND HANDLING
1.5.1 Delivery and Storage
Inspect materials delivered to the site for damage, and store with a minimum of handling. Store materials on
site in enclosures or under protective coverings. Store plastic piping under cover out of direct sunlight.
Do not store materials directly on the ground. Keep inside of pipes and fittings free of dirt and debris.
1.5.2 Handling
Handle pipe and components carefully to ensure a sound, undamaged condition. Take particular care not to damage
pipe coating. Repair damaged coatings to original finish. Do not place pipe or material of any kind inside
another pipe or fitting after the coating has been applied, except as specified in paragraph INSTALLATION. Handle
steel piping with coal-tar enamel coating in accordance with AWWA C203, and fusion-bonded epoxy coatings per
AWWA C213. Handle plastic pipe in conformance with AGA XR0603.
1.6 EXTRA MATERIALS
Submit spare parts data for each different item of equipment and material specified, after approval of the detail
shop drawings and not later than [_____] months prior to the date of beneficial occupancy. Include in the data
a complete list of parts and supplies, with current unit prices and source of supply.
PART 2 PRODUCTS
2.1 PIPE, FITTINGS, AND ASSOCIATED MATERIALS
Provide materials and equipment which are the standard products of a manufacturer regularly engaged in the manufacture
of the products and that essentially duplicate items that have been in satisfactory use for at least 2 years
prior to bid opening. Asbestos or products containing asbestos are not allowed. Provide written verification
and point of contact for a supporting service organization that is, in the opinion of the Contracting Officer,
reasonably convenient to the site. Mark all valves, flanges, and fittings in accordance with MSS SP-25. Submit
a complete list of materials and equipment, including manufacturer's descriptive and technical literature, performance
charts and curves, catalog cuts, and installation instructions, including, but not limited to the following:
a. Dielectric Waterways and Flange Kits.
b. Emergency Gas Supply Connection.
c. Fittings
d. Piping
e. Pipe and Accessory coatings
f. Pressure Reducing Valves.
g. Meters
h. Regulators.
i. Shut-off Valves
j. [_____] Earthquake Actuated Automatic Gas Shut-off System conforming to ASCE 25.
2.1.1 Steel Pipe
NOTE: Delete all words in brackets when steel pipe is expected to be subjected
to unusually severe conditions (including handling) such as impact stresses,
seismic forces, burial beneath vehicle or railroad crossings, significant differential
settlement, or underneath piers.
API Spec 5L, Grade [A,] B, or X42, [ASTM A 53/A 53M, Grade A or B, ASTM A 135/A 135M, or ASTM A 139/A 139M, Grade
A or B], Schedule 40. Do not coat pipe and fittings for aboveground lines. Provide butt weld wrought steel
fittings, conforming to ASME B16.9, Schedule 40. Provide forged steel socket weld and threaded fittings , conforming
to ASME B16.11. Verify that pipe wall thickness conforms to ASME B31.8 for larger sizes and high pressures.
2.1.2 Small Fittings
For sizes 40 mm 1-1/2 inches and smaller, provide fittings conforming to ASME B16.11.
2.1.3 Fittings, 50 mm 2 inches and Larger
Provide pipe flanges and flanged fittings, including bolts, nuts, and bolt patterns in accordance with ASME B16.5
, Class [_____]. Provide buttweld fittings in accordance with ASME B16.9. Use weld neck flanges.
2.1.4 Steel Forged Branch Connections
Provide steel forged branch connections conforming to ASTM A 181/A 181M, Class 60, carbon steel.
2.1.5 Flange Gaskets
Provide non-asbestos compressed material gaskets in accordance with ASME B16.21, 1.6 mm 1/16 inch minimum thickness,
full face or self-centering flat ring type, containing aramid fibers bonded with nitrile butadiene rubber (NBR),
or glass fibers bonded with polytetrafluoroethylene, suitable for maximum 315 degrees C 600 degrees F service
and meeting applicable requirements of ASME B31.8.
2.1.6 Pipe Threads
Provide threaded pipe conforming to ASME B1.20.1.
[2.1.7 Polyethylene Pipe, Tubing, Fittings and Joints
NOTE: Before selecting polyethylene or fiberglass pipe material, contact the
gas supplier for a gas analysis to determine the types of chemicals which will
be in the gas to be supplied. Select suitable polyethylene or fiberglass pipe
material based on the gas analysis.
Do not use polyethylene for gas lines with design pressures above 690 kPa (100
psig) or with operating temperatures below 7 degrees C (20 degrees F) or above
60 degrees C (140 degrees F).
For thermoplastic (polyethylene) pipe in sizes from 15 mm through 150 mm (1/2
inch through 6 inches), select minimum wall thickness based on ASME B31.8, table
842.32(c); and select the standard dimension ratio (SDR) based on the long-term
hydrostatic strength of S = 8.6 MPa (1,250 psi) for PE 2406 or S = 11 MPa (1,600
psi) for PE 3408 at 23 degrees C (73 degrees F) for the following pressures:
Design Pressure
SDR at 23 degrees C (73 Degrees F)
S = 8.62 MPa (1,250 psi) S = 11 MPa (1,600 psi)
11 550 kPa (80 psig) 690 MPa (100 psig)
13.5 415 kPa (60 psig) 550 kPa (80 psig)
17 345 kPa (50 psig) 415 kPa (60 psig)
21 275 kPa (40 psig) 345 kPa (50 psig)
26 207 kPa (30 psig) 275 kPa (40 psig)
Where the buried pipe system is expected to exceed 23 degrees C (73 degrees
F) at the design pressures stated above, use alternate materials.
Provide polyethylene pipe, tubing, fittings and joints conforming to ASTM D 3350 and ASTM D 2513, pipe designations
PE 2406 and PE 3408, rated SDR [_____] or less, as specified in ASME B31.8. Mark pipe sections as required by
ASTM D 2513. Provide butt fittings conforming to ASTM D 3261 and socket fittings conforming to ASTM D 2683.
Match fittings to the service rating of the pipe, with a minimum wall thickness of [_____].[ Use polyethylene
pipe, tubing, and fittings as recommended by the manufacturer for use with LPG.] Perform underground installations
in conformance with ASTM D 2774.
][2.1.8 Fiberglass Pipe, Fittings and Adhesive
Provide fiberglass pipe, fittings and adhesive conforming to ASTM D 2517. Mark pipe sections as required by
ASTM D 2517, with [_____] minimum wall thickness. Perform underground installations in conformance with ASTM D 3839
.
]2.1.9 Sealants for Steel Pipe Threaded Joints
2.1.9.1 Sealing Compound
Provide joint sealing compound as listed in UL Gas&Oil Dir, Class 20 or less.
2.1.9.2 Tape
Provide polyetrafluoroethylene tape conforming to ASTM D 3308.
2.1.10 Identification
Provide pipe flow markings and metal tags for each valve, meter, and regulator as required by the Contracting
Officer.
2.1.11 Insulating Joint Materials
Provide insulating joint materials between flanged or threaded metallic pipe systems where shown to isolate galvanic
or electrolytic action.
2.1.11.1 Threaded Joints
For threaded pipe joints, provide steel body nut type, dielectric waterways with insulating gaskets.
2.1.11.2 Flanged Joints
For flanged pipe joints, provide full face sandwich-type flange insulating gasket of the dielectric type, insulating
sleeves for flange bolts and insulating washers for flange nuts.
2.1.11.3 Dielectric Waterways and Flanges
Provide dielectric waterways with temperature and pressure rating equal to or greater than that specified for
the connecting piping, with metal connections on both ends suited to match connecting piping. Provide internally
lined dielectric waterways, lined with an insulator specifically designed to prevent current flow between dissimilar
metals, meeting the performance requirements described herein for dielectric waterways.
2.1.12 Gas Transition Fittings
Provide manufactured steel gas transition fittings approved for jointing steel and polyethylene or fiberglass
pipe, conforming to AGA XR0603 requirements for transition fittings.
2.2 VALVES
NOTE: Valves and pressure regulators are necessary at all points where design
requires pressure reduction or regulation. Require a shut-off valve upstream
of the regulator. A central regulating station is generally provided by the
gas company and is usually located near the entrance to the installation. When
valves, gas pressure regulators, and related devices are required in the contract,
ensure that all necessary equipment will comply with the requirements of the
gas company, and revise these paragraphs as required. Provide a detail of each
regulating station and the following data for each pressure regulator: materials
of construction, flow rate, type and specific gravity of the gas, inlet and
outlet pressures, accuracy of control, and size and type of connections.
Provide valves suitable for shutoff or isolation service and conforming to [MSS SP-110][, MSS SP-72] [, MSS SP-78
]and the following:
2.2.1 Steel Valves
Provide steel valves 40 mm 1-1/2 inches and smaller installed underground conforming to ASME B16.34, carbon steel,
socket weld ends, with square wrench operator adaptor. Provide steel valves 40 mm 1-1/2 inches and smaller installed
aboveground conforming to ASME B16.34, carbon steel, socket weld or threaded ends with handwheel or wrench operator.
Provide steel valves 50 mm 2 inches and larger installed underground conforming to API Spec 6D, carbon steel,
buttweld ends, Class [_____] with square wrench operator adaptor. Provide steel valves 50 mm 2 inches and larger
installed aboveground conforming to API Spec 6D, carbon steel, buttweld or flanged ends, Class [_____] with handwheel
or wrench operator.
2.2.2 Steel Valve Operators
Provide valves 200 mm 8 inches and larger with worm or spur gear operators, totally enclosed, grease packed,
and sealed, with operators having Open and Closed stops and position indicators. Provide locking feature where
indicated. Wherever the lubricant connections are not conveniently accessible, provide extensions for the application
of lubricant. Provide valves with lubricant compatible with gas service.
2.2.3 Polyethylene Valves
Provide polyethylene valves conforming to ASME B16.40. Polyethylene valves, in sizes 15 mm to 150 mm 1/2 inch
to 6 inches, may be used with polyethylene distribution and service lines, in lieu of steel valves, for underground
installation only.
2.3 PRESSURE REGULATORS
NOTE: Coordinate this paragraph with the specified requirements in paragraph
VALVES.
Provide ferrous bodied regulators with backflow protection, designed to meet the pressure, load and other service
conditions.
2.3.1 Gas Main Regulators
Equip pressure regulators for main distribution lines, supplied from a source of gas which is at a higher pressure
than the maximum allowable operating pressure for the system, with pressure regulating devices of adequate capacity.
In addition to the pressure regulating devices, provide a protective method to prevent overpressuring of the
system in accordance with ASME B31.8. Suitable protective devices are as follows:
a. Spring-loaded relief valve meeting the provisions of ASME BPVC SEC VIII D1.
b. Pilot-loaded back pressure regulator used as relief valve, so designed that failure of the pilot
system will cause the regulator to open.
c. Weight-loaded relief valves conforming to ASME PTC 25.
d. Monitoring regulator installed in series with the primary pressure regulator.
e. Series regulator installed upstream from the primary regulator, set to limit the pressure on the
inlet of the primary regulator continuously to the maximum allowable operating pressure of the system,
or less.
f. Automatic shutoff device installed in series with the primary regulator, set to shut off when the
pressure on the distribution system reaches the maximum allowable operating pressure of the system, or
less, which remains closed until manually reset.
g. Spring-loaded, diaphragm type relief valves.
2.3.2 Service Line Regulators
NOTE: If service regulator does not have all the characteristics listed, or
if gas contains materials which would interfere with operation of the regulator,
install protective devices to prevent overpressuring of the user's system should
the regulator fail. Install the following devices as an integral part of the
regulator or as separate devices operating in conjunction with the regulator.
a. Monitoring regulator
b. Relief valve
c. Automatic shutoff device
a. Provide ferrous bodied pressure regulators for individual service lines, capable of reducing distribution
line pressure to pressures required for users. Provide regulators where gas will be distributed at
pressures in excess of 2.5 kPa 10 inches of water column, with pressure relief set at a lower pressure
than would cause unsafe operation of any connected user.
b. Adjust regulators for liquified petroleum gas to 2.5 to 3 kPa 10 to 12 inches of water column, with
pressure relief set at 4 kPa 16 inches of water column.
c. Provide regulator(s) having a single port with orifice diameter no greater than that recommended
by the manufacturer for the maximum gas pressure at the regulator inlet. Provide regulator valve vent
of resilient materials designed to withstand flow conditions when pressed against the valve port, capable
of regulating downstream pressure within limits of accuracy and limiting the buildup of pressure under
no-flow conditions to 50 percent or less of the discharge pressure maintained under flow conditions.
Provide a self contained service regulator, and pipe not exceeding exceed 50 mm2 inch size.
2.4 METERS
NOTE: Provide gas meters for each service line to every building. Where meters
have a maximum anticipated demand of less than 28 cubic meters/hour (1000 SCFH),
require the meter to meet a design working pressure of 690 kPa (100 psi).
Delete mounting and special features that are not required. Retain strainer
upstream of meter only if installed upstream of pressure regulator. Delete
pulse switch and pulse requirements except for Air Force projects or when required
by other users. Air Force Engineering Technical Letter Number 87-5 "Utility
Meters in New and Renovated Facilities" provides guidance for when to exclude
meters from Air Force new and major renovation projects. Review the requirements
for gas meters in TI 800-01 Design Criteria and 10 CFR 435.
Provide meters conforming to AGA B109.2, [pipe] [pedestal] mounted [and be provided with a strainer immediately
upstream]. [Provide meters with [over-pressure protection as specified in ASME B31.8] [tamper-proof protection]
[frost protection] [fungus-proof protection][seismic protection], suitable for accurately measuring and handling
gas at pressures, temperatures, and flow rates indicated.] Provide meters with a pulse switch initiator capable
of operating up to speeds of 500 maximum pulses per minute with no false pulses and requiring no field adjustments.
Provide not less than one pulse per 2.83 cubic meter 100 cubic feet of gas.
2.5 EARTHQUAKE ACTUATED AUTOMATIC GAS SHUTOFF SYSTEM
NOTE: Include earthquake actuated automatic gas shutoff system if the facility
is either essential or hazardous. Determine the classification of the facility
per UFC 3-310-03A and provide a detail on the drawings showing this system.
ASCE has developed a "Public-Approved Version" of ASCE 25 - Standard Specification
for EARTHQUAKE ACTUATED AUTOMATIC GAS SHUTOFF DEVICES, dated 2008, which includes
a test procedure to verify that the valve will activate during strong ground
shaking but will not activate for minor ground shaking or accidental bumping
by a pedestrian or vehicle.
The State of California, Division of the State Architect/Real Estate Services
Division maintains a list of devices that have been tested and conform to the
ASCE Standard; inquiries can be directed to telephone No. 916-445-2600.
Show the earthquake actuated automatic gas shutoff on the drawings when required
in the project. The designer must fill the bracketed blank for additional local
requirements, and ensure that a copy is included with the Contract documents.
Provide Earthquake Actuated Automatic Gas Shutoff devices conforming to ASCE 25, [UL or AGA listed][_____] [and]
[requirements furnished by the Contracting Officer] [ as listed by the State of [California] [_____], Division
of the State Architect as being tested and in conformance with specified requirements]. The valve may be either
pendulum or ball construction with [remote [, pneumatic] [electronic] [or] [electric]] actuator.
2.6 EMERGENCY GAS SUPPLY CONNECTION
NOTE: Include emergency gas supply connections when the customer determines
the ability to provide gas to the building is necessary during an outage of
the gas distribution system. Show the emergency gas piping connection on the
drawings when required in the project.
Provide an emergency gas supply connection consisting of piping (same size as service line) and accessories
that will enable a portable, commercial-sized gas cylinder system to be connected to the gas piping system.
Cap this connection to prevent gas leakage with a lockable manual valve located to allow shutting off flow.
Provide the entire assembly in a weatherproof, lockable box, with permanently installed written instructions
stating the type and pressure of the gas allowed to be connected to the line, and providing specific instruction
for testing of the integrity of the building's gas system with an inert gas before the fuel gas connection is
made. Provide a subplate in the box that is required to be unbolted to gain access to the connection, and containing
a warning regarding the potential consequences of using gas other than that specified or of failing to test system
integrity before hooking up emergency fuel supply.
2.7 PROTECTIVE COVERING MATERIALS
Provide a continuously extruded polyethylene and adhesive coating system material conforming to NACE SP0185,
Type A.
2.8 TELEMETERING OR RECORDING GAUGES
NOTE: On distribution systems supplied by a single district pressure regulating
station, determine the necessity of installing telemetering or recording gauges
in the supply line, taking into consideration the number of buildings supplied,
the operating pressures, the capacity of installation, and other operating conditions.
Equip each distribution system supplied by more than one district pressure regulating station with telemetering
or recording pressure gauges to indicate the gas pressure in the district line.
PART 3 EXECUTION
3.1 EXAMINATION
After becoming familiar with all details of the work, verify all dimensions in the field, and advise the Contracting
Officer of any discrepancy before performing the work.
3.2 EXCAVATION AND BACKFILLING
Earthwork is as specified in Section 31 00 00 EARTHWORK.
3.3 GAS MAINS
Provide [steel] [polyethylene] [or] [fiberglass]pipe for gas mains. [Coat steel pipe and fittings with protective
covering as specified.] [Do not install polyethylene or fiberglass mains aboveground.]
3.4 SERVICE LINES AND EMERGENCY GAS SUPPLY CONNECTION
3.4.1 General
NOTE: Locate service line isolation valve as close to the supply main as possible,
but at a safe distance from traffic lanes.
Construct service lines of materials specified for gas mains and extend from a gas main to and including the
point of delivery within 1.5 meters 5 feet of the building. The point of delivery is the [meter set assembly]
[service regulator] [shutoff valve]. Connect the service lines to the gas mains [as indicated] [through service
tees, with end of run plugged]. Where indicated, provide service line with an isolation valve of the same size
as the service line. Make the service lines as short and as straight as practicable between the point of delivery
and the gas main, without bends or lateral curves unless necessary to avoid obstructions or otherwise permitted.
Lay service lines with as few joints as practicable using standard lengths of pipe, use shorter lengths only
for closures. Do not install polyethylene or fiberglass service lines aboveground [except as permitted in ASME B31.8
].
3.4.2 Emergency Gas Supply Connection
NOTE: If it is expected that a portable gas tank providing pressure regulated
gas would be provided during an emergency, locate the emergency gas connection
downstream from the building's pressure regulator.
Provide an aboveground locked, valved and capped emergency gas supply connection [downstream] [upstream] of the
pressure regulator, located outside of the building within 300 mm12 inches of the exterior wall and installed
in a weatherproof box which is mounted on the exterior wall and clearly marked with an appropriate metal sign
mounted on wall above.
3.5 WORKMANSHIP AND DEFECTS
Make pipe, tubing, and fittings clear and free of cutting burrs and defects in structure or threading, and thoroughly
brushed and blown free of chips and scale. Do not repair, but replace defective pipe, tubing, or fittings.
3.6 PROTECTIVE COVERING
3.6.1 Protective Covering for Underground Steel Pipe
Except as otherwise specified, apply protective coverings mechanically in a factory or field plant especially
equipped for the purpose. Hand apply protective covering to valves and fittings that cannot be coated and wrapped
mechanically, preferably at the plant that applies the covering to the pipe. Coat and wrap joints by hand, in
a manner and with materials that will produce a covering equal in thickness to that of the covering applied mechanically.
3.6.1.1 Thermoplastic Resin Coating System
Provide a thermoplastic coating system conforming to NACE SP0185, Type A. Clean the exterior of the pipe to
a commercial grade blast cleaning finish in accordance with SSPC SP 6, and apply adhesive compound to the pipe.
Immediately after the adhesive is applied, extrude a seamless tube of polyethylene over the adhesive to produce
a bonded seamless coating, with a nominal thickness of 0.25 mm 10 mils (plus or minus 10 percent) of adhesive
and 1.0 mm 40 mils (plus or minus 10 percent) of polyethylene for pipes up to 400 mm 16 inches in diameter.
For pipes 450 mm 18 inches and larger in diameter, apply a minimum thickness to the pipe of 0.25 mm 10 mils
(plus or minus 10 percent) adhesive and 1.5 mm 60 mils (plus or minus 10 percent) polyethylene. Apply joint
coating and field repair material as recommended by the coating manufacturer, consisting of one the following:
a. Heat shrinkable polyethylene sleeves.
b. Polyvinyl chloride pressure-sensitive adhesive tape.
c. High density polyethylene/bituminous rubber compound tape.
Inspect the coating system for holes, voids, cracks, and other damage during installation.
3.6.1.2 Inspection of Pipe Coatings
Repair any damage to the protective covering during transit and handling before installation. After field coating
and wrapping has been applied, inspect the entire pipe using an electric holiday detector with impressed current
set at a value in accordance with NACE RP0274 using a full-ring, spring-type coil electrode. Equip the holiday
detector with a bell, buzzer, or other type of audible signal which sounds when a holiday is detected. Immediately
repair all holidays in the protective covering upon detection. The Contracting Officer reserves the right to
inspect and determine the suitability of the detector. Furnish labor, materials, and equipment necessary for
conducting the inspection.
3.6.2 Protective Covering for Aboveground Piping Systems
Apply finish painting conforming to the applicable paragraphs of Section 09 90 00 PAINTS AND COATINGS and as
follows:
3.6.2.1 Ferrous Surfaces
Touch up shop primed surfaces with ferrous metal primer of the same type paint as the shop primer. Solvent-clean
surfaces that have not been shop primed in accordance with SSPC SP 1. Mechanically clean surfaces that contain
loose rust, loose mill scale, and other foreign substances by power wire brushing in accordance with SSPC SP 3
or brush-off blast clean in accordance with SSPC SP 7 and primed with ferrous metal primer in accordance with
SSPC Paint 25. Finish primed surfaces with two coats of exterior alkyd paint conforming to MPI 9.
3.6.2.2 Nonferrous Surfaces
NOTE: Retain only the first sentence for normal conditions; delete the first
sentence for corrosive conditions.
[Do not paint nonferrous surfaces.] [Paint nonferrous surfaces to corrosive conditions. Solvent-clean the surfaces
in accordance with SSPC SP 1. Apply a first coat of MPI 10, and 2 coats of [MPI 119] [or] [MPI 11].]
3.6.3 Protective Covering for Piping in Valve Boxes and Manholes
Apply protective coating to piping in valve boxes or manholes as specified for underground steel pipe.
3.7 INSTALLATION
NOTE: When existing gas piping is abandoned, show disconnect details on the
drawings. Refer to ASME B31.8 for guidance on preparing the disconnect details.
ASME B31.8 requires physical disconnection from gas sources. Shutoff valves
are not an acceptable means of disconnect.
Install gas distribution system and equipment in conformance with the manufacturer's recommendations and applicable
sections of ASME B31.8, AGA XR0603 and 49 CFR 192. Perform abandonment of existing gas piping in accordance
with ASME B31.8. Cut the pipe damaging the pipe; unless otherwise authorized, use an approved type of mechanical
cutter. Use wheel cutters where practicable. On steel pipe 150 mm6 inches and larger, an approved gas-cutting-and-beveling
machine may be used. Cut plastic pipe in accordance with AGA XR0603. Design valve installation in plastic pipe
to protect the plastic pipe against excessive torsional or shearing loads when the valve is operated and from
other stresses which may be exerted through the valve or valve box.[ Install polyethylene mains and service
lines for LPG only below ground in accordance with NFPA 58.]
3.7.1 Installing Pipe Underground
NOTE: Indicate profile of gas lines on the drawing. If it is impractical to
comply with the minimum cover specified for pipe, and necessary to prevent damage
from external loads, the pipe will be installed in a casing. The locations
of all casings and details of the installation will be indicated.
Grade gas mains and service lines as indicated. Weld joints in steel pipe except as otherwise permitted for
installation of valves. Provide mains with 600 mm 24 inch minimum cover; service lines with 485 mm 18 inch minimum
cover; and place both mains and service lines on firmly compacted select material for the full length. Where
indicated, encase, bridge, or design the main to withstand any anticipated external loads as specified in ASME B31.8
. Provide standard weight black steel pipe encasement material with a protective coating as specified. Separate
the pipe from the casing by insulating spacers and seal the ends with casing bushings. Excavate the trench below
pipe grade, bed with bank sand, and compact to provide full-length bearing. Laying pipe on blocks to produce
uniform grade is not permitted. Ensure that the pipe is clean inside before it is lowered into the trench and
keep free of water, soil, and all other foreign matter that might damage or obstruct the operation of the valves,
regulators, meters, or other equipment. When work is not in progress, securely close open ends of pipe or fittings
with expandable plugs or other suitable means. Minor changes in line or gradient of pipe that can be accomplished
through the natural flexibility of the pipe material without producing permanent deformation and without overstressing
joints may be made when approved. Make changes in line or gradient that exceed the limitations specified with
fittings. When cathodic protection is furnished, provide electrically insulated joints or flanges. When polyethylene
or fiberglass piping is installed underground, place foil backed magnetic tape above the pipe to permit locating
with a magnetic detector. After laying of pipe and testing, backfill the trench in accordance with Section
31 00 00 EARTHWORK.
3.7.2 Installing Pipe Aboveground
Protect aboveground piping against dirt and other foreign matter, as specified for underground piping. Weld
joints in steel pipe ; however, joints in pipe 40 mm 1-1/2 inches in diameter and smaller may be threaded; joints
may also be threaded to accommodate the installation of valves. Provide flanges of the weld neck type to match
wall thickness of pipe.
3.8 PIPE JOINTS
Design and install pipe joints to effectively sustain the longitudinal pullout forces caused by the contraction
of piping or superimposed loads.
3.8.1 Threaded Steel Joints
Provide threaded joints in steel pipe with tapered threads evenly cut, made with UL approved graphite joint sealing
compound for gas service or polytetrafluoroethylene tape applied to the male threads only. Caulking of threaded
joints to stop or prevent leaks is not permitted.
3.8.2 Welded Steel Joints
Perform gas pipe weldments as indicated. Make changes in direction of piping by welding fittings only; mitering
or notching pipe to form elbows and tees or other similar type construction is not permitted. Branch connection
may be made with either welding tees or forged branch outlet fittings. Use forged or flared branch outlet fittings
for improvement of flow where attached to the run, and reinforced against external strains. Perform all beveling,
alignment, heat treatment, and inspection of welds conforming to ASME B31.8. Remove weld defects and repair
the weld, or remove the weld joints entirely and reweld. After filler metal has been removed from its original
package, protect it or store so that its characteristics or welding properties are not affected adversely. Do
not use electrodes that have been wetted or have lost any of their coating.
3.8.3 Polyethylene and Fiberglass Pipe Jointing Procedures
Use jointing procedures conforming to AGA XR0603. Avoid making indiscriminate heat fusion joining of plastic
pipe or fittings made from different polyethylene resins by classification or by manufacturer if other alternative
joining procedures are available. If heat fusion joining of dissimilar polyethylene is required, special procedures
are required. Test the method of heat fusion joining dissimilar polyethylene resins in accordance with paragraph
TESTS, subparagraph Destructive Tests of Plastic Pipe Joints.
3.8.4 Connections Between Metallic and Plastic Piping
Only make metallic to plastic connections outside, underground, and with approved transition fittings.
3.9 VALVE BOXES
Provide valve boxes of cast iron not less than 4.7 mm 3/16 inch thick at each underground valve except where
concrete or other type of housing is indicated. Provide valve boxes with locking covers that require a special
wrench for removal, and furnish the correctly marked wrench for each box. Cast the word "gas" in the box cover.
When the valve is located in a roadway, protect the valve box by a suitable concrete slab at least 1 square meter
3 square feet. When in a sidewalk, provide the top of the box as a removable concrete slab 600 mm 2 feet square
and set flush with the sidewalk. Make the boxes adjustable extension type with screw or slide-type adjustments.
Separately support valve boxes to not rest on the pipe, so that no traffic loads can be transmitted to the pipe.
Only locate valves valve boxes or inside of buildings.
[3.10 DRIPS
NOTE: If gas mains are for the distribution of high-pressure natural gas (above
400 kPa (60 psig)) only, delete the entire paragraph: DRIPS. Require drips
for lines transmitting natural gas at the low point immediately following reduction
from high pressure (above 400 kPa (60 psig)) to medium pressure (400 kPa (60
psig) or less), and at occasional low points throughout the system, to provide
for blowing out the lines. Require drips at all low points in lines transmitting
manufactured gas or a mixture of manufactured and natural gas. Indicate locations
of drips. Locate drip points to provide for proper drainage of pipe system.
Detail drips and discharge terminal (outlet) piping. If the need to contain
and dispose of liquids through the valve for environmental concerns is required,
delete the first bracketed sentence.
Install drips at locations where indicated, conforming to the details shown, or provide commercial units of approved
type and capacity. Connect a blow off pipe 32 mm 1-1/4 inches or larger to each drip at its lowest point and
extend to or near the ground surface at a convenient location away from traffic. Provide a reducing fitting
for each discharge at each drip terminal (outlet), a plug valve, and a 15 mm 1/2 inch nipple turned down. Locate
the discharge terminal (outlet) inside a length of 300 mm 12 inches or larger vitrified clay pipe, concrete sewer
pipe or concrete terminal box [set vertically on a bed of coarse gravel 300 mm 1 foot thick and 1 m3 feet square,]
[with concrete bottom to contain liquids and a connection to remove liquids for disposal,] and closed at the
ground surface with a suitable replacement cover.
]3.11 PRESSURE REGULATOR INSTALLATION
3.11.1 Main Distribution Line Regulators
NOTE: Remove reference to bypasses around pressure regulators for main distribution
lines unless continuity of service is imperative and the bypass is regulated
to prevent possible overpressure of downstream lines.
Install pressure regulators where shown. Install a valve on each side of the regulator for isolating the regulator
for maintenance.[ Provide a bypass line with bypass valves or 3 way valves and an over-pressurization pressure
regulating device.] Install regulators and valves in rectangular reinforced concrete boxes, large enough so
that all required equipment can be properly installed, operated, and maintained, with box sidewalls extending
above ground line. Provide the boxes with [steel door] [cast iron manhole] covers with locking provisions and
100 mm 4 inch diameter vents. Furnish one key or other unlocking device with each cover. Locate discharge
stacks, vents, or outlet ports of all pressure relief devices where gas can be discharged into the atmosphere
without undue hazard. Provide stacks and vents with fittings to preclude entry of water.
3.11.2 Service Line Regulators
NOTE: Delete inapplicable requirements.
Install a shutoff valve,[ meter set assembly,] and service regulator on the service line outside the building,
450 mm 18 inches above the ground on the riser. Install an insulating joint on the inlet side of the [meter
set assembly and] service regulator and construct to prevent flow of electrical current. Provide a 10 mm 3/8
inch tapped fitting equipped with a plug on both sides of the service regulator for installation of pressure
gauges for adjusting the regulator. Terminate all service regulator vents and relief vents in the outside air
in rain and insect resistant fittings. Locate the open end of the vent where gas can escape freely into the
atmosphere, away from any openings into the building and above areas subject to flooding.
[3.12 METER INSTALLATION
NOTE: Air Force Engineering Technical Letter Number 87-5 "Utility Meters in
New and Renovated Facilities" provides guidance for when to exclude meters from
Air Force new and major renovation projects. Review the requirements for gas
meters in TI 800-01 Design Criteria and 10 CFR 435.
Install meters in accordance with ASME B31.8. Install permanent gas meters with provisions for isolation and
removal for calibration and maintenance, and suitable for operation in conjunction with an energy monitoring
and control system.
]3.13 CONNECTIONS TO EXISTING LINES
NOTE: If connections to existing mains are required, retain this subparagraph,
and select the appropriate Paragraph. Drawings will show existing gas lines
when interface with the existing gas system is required.
Make connections between new work and existing gas lines, where required, in accordance with ASME B31.8, using
proper fittings to suit the actual conditions. When connections are made by tapping into a gas main, provide
the same size connecting fittings as the pipe being connected.
3.13.1 Connections to Publicly or Privately Operated Gas Utility Lines
NOTE: Delete inapplicable requirements.
Provide materials for the connections to the existing gas lines. The Utility is to make final connections and
turn on the gas. The Utility is to also disconnect, purge and cap, plug or otherwise effectively seal existing
lines that are to be a abandoned or taken out of service. Notify the Contracting Officer, in writing, 10 days
before final connections and turning on of gas lines. Make necessary arrangements with the Utility for tie in
and activation of new gas lines. Only the Operating Agency/Utility Company may reactivate the system after tie
in. Furnish a certification by the Operating Agency/Utility Company that all Utility work has been satisfactorily
completed.
3.13.2 Connection to Government Owned/Operated Gas Lines
NOTE: Provide the name and location of the Utility or Operating Agency of the
existing gas lines. Show on the drawings, the location of valves to be operated
for existing system deactivation. When lines are to be abandoned, give consideration
to any effects the abandonment may have on an active cathodic protection system
and take appropriate action. If the segment is long and there are few line
valves, give consideration to plugging the abandoned segment at intervals.
Provide connections to the existing gas lines in accordance with approved procedures. Only perform deactivation
of any portion of the existing system at the valve location shown on the drawings. Reactivation of any existing
gas lines will only be done by the [Government] [local Utility] [Operating Agency]. Submit the approved Contractor's
Connection and Abandonment Plan prior to making any connections to existing gas lines, manicure the [Operating
Agency's] [Utility's] required procedures which may be obtained from [_____]. Notify the Contracting Officer,
in writing, 10 days before connections to existing lines are to be made.
a. Physically disconnect from the pipeline system if facilities are abandoned in place. Purge, cap,
plug or otherwise effectively seal the open ends of all abandoned facilities. Do not complete abandonment
until it has been determined that the volume of gas or liquid hydrocarbons contained within the abandoned
section poses no potential hazard. Use air or inert gas for purging, or fill the facility with water
or other inert material. If air is used for purging, ensure that a combustible mixture is not present
after purging.
b. When a main is abandoned, together with the service lines connected to it, only the customer's end
of such service lines is required to be sealed as stipulated above.
c. Disconnect abandoned service lines from the active mains as close to the main as practicable.
d. Close all valves left in the abandoned segment.
e. Remove all above grade valves, risers, and vault and valve box covers. Fill vault and valve box
voids with suitable compacted backfill material.
3.14 CATHODIC PROTECTION
NOTE: Cathodic protection is mandatory for underground metallic gas distribution
lines. Select the type and design of cathodic protection in accordance with
UFC 3-570-02A. Provide testing stations for the cathodic protection system.
Provide cathodic protection for all metallic gas piping installed underground and install as specified in [Section
26 42 14.00 10 - CATHODIC PROTECTION SYSTEM (SACRIFICIAL ANODE)] [Section 26 42 17.00 10 - CATHODIC PROTECTION
SYSTEM (IMPRESSED CURRENT)].
3.15 TESTS
[3.15.1 Destructive Tests of Plastic Pipe Joints
NOTE: Destructive tests of plastic pipe joints are provided as a designer option.
Destructive tests are considered useful in assuring that good joints will be
made. Delete the paragraph if this option is not exercised.
Each day, prior to making polyethylene heat fusion joints or fiberglass adhesive joints, make a joint of each
size and type to be installed that day by each person performing joining of plastic pipe that day and destructively
test. Cut at least 3 longitudinal straps from each joint. Visually examine each strap for voids or discontinuities
on the cut surfaces of the joint area, deformations by bending, torque, or impact. If failure occurs, it must
not initiate in the joint area. If a joint fails the visual or deformation test, the qualified joiner who made
that joint is not allowed to make further field joints in plastic pipe on this job until that joiner has been
retrained and re-qualified. Record the results of the destructive tests including the date and time of the tests,
size and type of the joints, ambient conditions, fusion iron temperature and names of inspectors and joiners.
]3.15.2 Pressure and Leak Tests
NOTE: Specify correct test pressure (including Class Location) to be used for
tests of gas line systems in accordance with ASME B31.8. Specify correct test
pressure (including Class Location) to be used for tests of gas line systems
in accordance with NFPA 58. Test pressures should recognize the weakest component
of each system tested for the design pressure, the maximum allowable operating
pressure, and the gas supplier's maximum operating pressure.
The test pressure will be 150 percent of the maximum operating pressure or 350
kPa (50 psig), whichever is greater. However, the maximum test pressure must
not be more than three times the design pressure of the pipe.
Test the system of gas mains and service lines after construction and before being placed in service, using air
as the test medium. Conform testing to ASTM D 1598 and ASTM D 1599 for plastic piping. The normal operating
pressure for the system is [_____]. The test pressure is [_____].
a. Prior to testing the system, blow-out, clean, and clear the interior of all foreign materials. Remove
all meters, regulators, and controls before blowing out and cleaning,and reinstall after clearing of
all foreign materials.
b. Perform testing of gas mains and service lines with due regard for the safety of employees and the
public during the test. Keep persons not working on the test operations out of the testing area while
testing is proceeding. Perform the test on the system as a whole or on sections that can be isolated.
c. Test joints in sections prior to backfilling when trenches will be backfilled before the completion
of other pipeline sections. Continue the test for at least 24 hours from the time of the initial readings
to the final readings of pressure and temperature. Do not take the initial test readings of the instrument
for at least 1 hour after the pipe has been subjected to the full test pressure. Do not take initial
or final readings at times of rapid changes in atmospheric conditions, and temperatures are representative
of the actual trench conditions. No indication of reduction of pressure is allowed during the test after
corrections have been made for changes in atmospheric conditions in conformity with the relationship
T(1)P(2)=T(2)P(1), in which T and P denote absolute temperature and pressure, respectively, and the numbers
denote initial and final readings.
d. During the test, completely isolate the entire system from all compressors and other sources of air
pressure. Test each joint by means of soap and water or an equivalent nonflammable solution prior to
backfilling or concealing any work. Secure approval of testing instruments from the Contracting Officer.
Furnish all labor, materials and equipment for conducting the tests subject to inspection at all times
during the tests. Maintain safety precautions for air pressure testing at all times during the tests.