CMC · California Mechanical Code
What joining methods and compatibility requirements must be followed?
In plain terms: pick piping materials and joints that are rated for the system pressure and temperature and chemically compatible with the fluid; use only the joining methods the product manufacturer or the adopted standards allow (for plastics that commonly means butt‑fusion, electrofusion, socket‑fusion, or listed mechanical fittings), follow the manufacturer’s installation instructions and the referenced ASTM/standards, and do not disturb fusion joints until they cool. If you need the exact code wording for **§ 1406.1**, I couldn’t find that section verbatim in the uploaded files — consult the adopted CMC text/Chapter 18 referenced standards and your AHJ for the final authority.
Last reviewed: July 6, 2026
What the code requires — 2–4 sentences
The California Mechanical Code identifies that piping and tubing must meet the working temperature and pressure of the system and that materials must be compatible with the transfer medium to avoid chemical attack, deformation or failure — this is the controlling policy the code applies when selecting joining methods (see § 1406.1 as the controlling section requested). The CMC directs use of approved materials, manufacturer's installation instructions and the referenced standards (Chapter 18) to determine allowable joining methods for a particular material and application. I could not retrieve the verbatim text of § 1406.1 in the files provided; the discussion below is grounded in the CMC excerpts and referenced-standards guidance that were retrieved.
The single most important rule: use materials and joining methods that are compatible with the fluid, the temperature/pressure, and the manufacturer/standard instructions — if the product or the standard doesn’t permit the joint, the code does not permit it.
Requirements in detail
1) Overarching requirements (what the code requires you to check)
- Material suitability — Piping/tubing must be rated for the system’s working temperature and working pressure, and compatible with the transfer medium to avoid chemical action or deformation.
- Follow manufacturer instructions and referenced standards — The CMC relies on referenced standards (Chapter 18) and the product manufacturer for acceptable joining methods and installation procedures; enforcement references those standards and manufacturer instructions.
2) How joining-method approval is determined (decision factors)
- Is the material listed/approved for the intended pressure/temperature? (if not — not acceptable)
- Does the manufacturer or an accepted standard (ASTM, ASME, etc.) list a permitted joint type for the specific pipe/fitting size and material? (required)
- Will the joint method produce a permanent, serviceable seal for the expected loads and environment? (required)
3) Specific/plastic (PE) example: common allowed methods (from referenced standards & plumbing code examples)
- For polyethylene and similar plastics the recognized heat- and mechanical-joining methods include butt-fusion, electro-fusion, socket-fusion, and mechanical/compression where listed by the manufacturer or referenced standard. The California plumbing guidance and referenced standards identify these methods and require ASTM practices (ASTM F2620 for butt-fusion; ASTM F1055 for electrofusion). Do not disturb heat-fusion/electrofusion joints until cooled to ambient temperature.
Decision table — at-a-glance (decision-relevant dimensions)
| Material / System | Typical allowed joining methods (decision) | Key decision criteria / limit | Code Reference |
|---|---|---|---|
| Generic piping (CMC requirement) | Use methods listed by manufacturer or referenced standards | Must meet working temperature, pressure, and compatibility with transfer medium | |
| Polyethylene (small sizes — ½" CTS to 1¼" IPS) | Electrofusion, Socket-fusion; Mechanical as alternate where listed | Follow manufacturer & ASTM; some materials (Aldyl-A) restrict heat iron fusion | |
| Polyethylene (2" IPS) | Electrofusion, Socket-fusion, Butt-fusion; mechanical as alternate | Use ASTM F2620 (butt) and ASTM F1055 (electro); align/ restrain per fitting instructions; do not disturb until cooled | |
| Polyethylene (3"–8" IPS) | Butt-fusion preferred; electrofusion as alternate | Large diameters typically joined by butt-fusion per ASTM practice | |
| Galvanized steel (plumbing reference) | Mechanical joints (elastomeric gasket) or Threaded joints (ASME B1.20.1 threads) | Thread sealant only on male threads; listed, approved sealant types | cite |
| PEX / PE-RT | Manufacturer-specified mechanical or crimp/compression systems | Must comply with referenced standards and manufacturer instructions; brass fittings must meet NSF/ANSI as required |
Notes:
- The CMC delegates technical details to the referenced standards tables (Chapter 18) and product/manufacturer instructions; check those references for the exact test procedures, fusion cycles, torque values, clamp spacing, etc.
- For plastics, plumbing-code materials and ASTM standards describe the fusion processes and required practices (see Table references and ASTM standards cited in the plumbing excerpts).
Exceptions & special cases
- If the product’s manufacturer expressly prohibits a joining method for that specific material (for example, some Aldyl‑A materials prohibit standard heat iron fusion), that prohibition controls — do not use a prohibited method even if a method would otherwise be common. (PG&E utility guidance documents document such prohibitions as industry practice.)
- The CMC/Chapter 18 approach means some specialized systems may have unique approved joining methods listed in other referenced standards; those referenced standards take precedence for the specific material/system.
- Where a transition is made between dissimilar materials (PE to steel, copper to plastic, etc.) use listed/approved adapters or transition fittings specifically intended for that transition; follow the fitting manufacturer’s welding/protection instructions (e.g., protect PE from welding heat).
Common mistakes
- Assuming “one joining method fits all” — many joining methods are tied to material, size and product listing; the CMC requires checking manufacturer/standard approvals first.
- Disturbing heat-fusion or electrofusion joints before they cool — the plumbing standard explicitly warns to not disturb joints until cooled to ambient temperature. This is a frequent field cause of weak joints.
- Using mechanical fittings on components not intended for them (for example, mechanical fittings on molded butt-fusion fittings) — utility guidance calls this out as not allowed. Always confirm compatibility of the fitting end with the coupling method.
- Failing to guard transitions from welding heat (e.g., welding steel end of transition fitting adjacent to PE) — overheating PE at transition joints is a documented hazard.
Worked example — choosing a joining method for a 2" IPS PE service riser
Scenario: You are installing a 2" IPS PE service riser in a mechanical room that will carry a neutral, non‑corrosive gas at low pressure.
- Code/standards check: For 2" IPS, recognized joining methods include electrofusion, socket-fusion, and butt-fusion (with mechanical only as an alternate for repair) — check manufacturer & ASTM references for the pipe and fittings.
- Material compatibility: Confirm the PE compound grade is suitable for the service pressure and ambient temperature per the manufacturer and ASTM F714 (or the product marking).
- Method selection: Choose electrofusion if the fitting is electrofusion‑rated (common indoors and for tie-in work). If using electrofusion:
- Align and restrain fitting to prevent movement.
- Apply the specified electrofusion cycle as provided by the fitting manufacturer/ASTM F1055.
- Do not disturb the joint until cooled to ambient temperature.
- Verification and records: Follow the manufacturer’s installation instructions and record the fusion parameters (serial number of fitting, cycle used, operator) per referenced-standard / AHJ practice. The CMC requires compliance with manufacturer instructions and referenced standards.
Related provisions
- § 1406.1 — controlling section requested (I could not retrieve the verbatim text of this section from the provided files; see note at top).
- Chapter 18 / referenced standards (Table 1801.1 and related) — CMC delegates the technical joining details and test/performance requirements to referenced standards listed in Chapter 18.
- For plastic/PE joining particulars (examples of referenced standards used in practice): see PE fusion and electrofusion descriptions that reference ASTM F2620 and ASTM F1055 in plumbing/industry guidance (useful for verifying the specific fusion process referenced by the CMC).
Note about sources and missing text
- The instructions asked for grounding on § 1406.1 specifically. I was unable to retrieve the verbatim text of § 1406.1 from the uploaded files; the guidance above is therefore grounded in the retrieved CMC excerpts about material/compatibility policy and Chapter 18 referenced standards, together with California plumbing code / industry guidance examples for plastic joining methods. For the definitive authoritative wording and any OSHPD/local amendments, consult the text of § 1406.1 and the Chapter 18 referenced standards in your adopted code set.
Code references
Grounded in the retrieved California Mechanical Code — click a citation to read the verbatim passage:
CMC § 90.2 High relevance — show source text
Locating wire gauge requirements for plastic pipe installations
- The Company will accept 14-gauge locating wire on existing plastic pipe service installations, installed prior to August 1, 2009, as long as the wire passes continuity tests. Applicant installers are not required to replace existing 14-gauge wire (that pass continuity tests) with 10-gauge on plastic services, and service stubs that have already been installed. However, all new plastic services and service stubs must be installed with 10-gauge wire in accordance with GDS A-90.2 and GDS A-90.3.
Pressure Test
- Main and stubs are required to be tested per GDS A-34.
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Page 17 of 17
GAS DESIGN STANDARD
INSTALLING AND MAINTAINING A
POLYETHYLENE (PE) GAS DISTRIBUTION SYSTEM
A-93.1
Publication Date: 12/15/2021 Effective Date: 03/01/2022 Rev. 11
Purpose and Scope
This gas design standard (GDS) provides requirements for installing and maintaining the Pacific Gas and Electric Company (PG&E or Company) polyethylene (PE) gas distribution system.
1 General Information
1.1. Joining PE
A. For approved joining methods, approved materials, and qualification requirements, see Appendix A.
B. Standard heat iron fusions are not allowed on Aldyl-A material. Use only electrofusion or mechanical fittings with Aldyl-A material.
C. Mechanical fittings are not allowed on molded butt fusion fittings such as 3-way tees, 90° elbows, 45° elbows, end caps, reducers, branch saddles, PE valves with molded ends, and tapping tees without pipe pups.
(1) Exception: ½ in. excess flow valves (EFVs) have molded ends but are made to pipe tolerances and are compatible with mechanical fittings.
1.2. Transitions from PE to Steel
CAUTION
If the transition joint is exposed to excessive heat when welding, the PE pipe could
become damaged.
A. Take precautions to protect the PE pipe at the point of transition when welding the steel end.
(1) Never shorten the steel portion of a transition fitting. Heat from welding can damage the PE pipe if the steel is cut.
(2) Protect the transition joint from excessive heat. Do not weld, thermite weld, or heat the body of the fitting; only butt welding of the steel end is permitted.
B. During this welding, protect the PE part of the heat-fusion transition fitting from overheating by wrapping the midpoint of the steel part of the fitting with wet cloth to remove heat. Keep the cloth wet during the weld. After completing the weld, leave the wet cloth on the fitting until the steel pipe is cool enough to touch.
Printed copies of this document might be out of date. The Technical Information Library (TIL) has the current version.
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Page 1 of 19
Installing and Maintaining a Polyethylene (PE)
A-93.1 Gas Distribution System
CMC § 705.4.1 High relevance — show source text
** Joining methods for galvanized steel pipe and fittings shall be installed in accordance with the manufacturer’s installation instructions and shall comply with Section 705.4.1 or Section 705.4.2. 705.4.1 Mechanical Joints. Mechanical joints shall be made with an elastomeric gasket. 705.4.2 Threaded Joints. Threaded joints shall be made with pipe threads that comply with ASME B1.20.1. Thread sealant tape or compound shall be applied only to male threads, and such material shall be of approved types, insoluble in water, and nontoxic. 705.5 Polyethylene (PE) Sewer Pipe. Polyethylene (PE) sewer pipe or tubing and fitting joining methods shall be installed in accordance with the manufacturer’s installation instructions and shall comply with Section 705.5.1 through Section 705.5.1.3.
705.5.1 Heat-Fusion Joints. Heat-fusion joints between PE sewer pipe or tubing and fittings shall be assembled in accordance with Section 705.5.1.1 through Section 705.5.1.3 using butt-fusion, electro-fusion, or socket-fusion heat methods. Do not disturb the joint until cooled to ambient temperature. 705.5.1.1 Butt-Fusion Joints. Butt-fusion joints for PE pipe shall be installed in accordance with ASTM F2620 and shall be made by heating the prepared ends of two pipes, pipe and fitting, or two fittings by holding ends against a heated element. The heated element shall be removed when the required melt or times are obtained and heated ends shall be placed together with applied force. Do not disturb the joint until cooled to ambient temperature.
705.5.1.2 Electro-Fusion Joints. Electro-fusion joints shall be heated internally by a conductor at the interface of the joint. Fittings shall comply with ASTM F1055 for the performance requirements of polyethylene electro-fusion fittings. The specified electro-fusion cycle used to form the joint requires consideration of the properties of the materials being joined, the design of the fitting being used, and the environmental conditions. Align and restrain fitting to pipe to prevent movement and apply electric current to the fitting. Turn off the current when the
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SANITARY DRAINAGE
required time has elapsed to heat the joint. Do not disturb the joint until cooled to ambient temperature.
705.5.1.3 Socket-Fusion Joints. Socket fusion joints shall be installed in accordance with ASTM F2620 and shall be made by simultaneously heating the outside surface of a pipe end and the inside of a fitting socket. Where the required melt is obtained, the pipe and fitting shall be joined by inserting one into the other with applied force. Do not disturb the joint until cooled to ambient temperature. 705.6 PVC and PVC Co-Extruded Plastic Pipe and Joining Methods. Joining methods for PVC plastic pipe and fittings shall be installed in accordance with the manufacturer’s installation instructions and shall comply with Section 705.6.1 through Section 705.6.3. 705.6.1 Mechanical Joints. Mechanical joints shall be designed to provide a permanent seal and shall be of the mechanical or push-on joint type.
CMC § 93.1 High relevance — show source text
” Applicant-Installed Work
Attachments
Attachment 1, “Illustration of a Direct Burial Main and Service Installation”
Revision Notes
Revision 7 has the following changes:
Incorporated content from Utility Bulletin TD-A-93.1B-001, “Mechanical Fittings Connections Use Clarification” to clarify what connections mechanical fittings can be used on.
Added guidance for fully replaced services, 1″ CTS is the preferred minimum pipe size but to consider ½″ pipe when inserting or splitting if adequate for service load and length.
Updated Table 1 to clarify preferred joining methods and alternate joining methods for PE pipe.
Clarified definition of hot tie-in for 2″ stab fittings.
Added guidance on parallel main installations for capacity jobs.
Updated guidance on methods used to vent casings on risers.
Removed old plastic pipe stamp and referenced GDS A-34 for leak test stamp requirements.
Removed table for bend radius in riser casing, as Table 2 will be adequate table to use for that scenario.
Asset Type: Distribution Services
Function: Design, Construction, and Maintenance
Document Contact: Gas Design Standard Responsibility List
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Page 15 of 17
Polyethylene Gas Distribution System Design A-90
Publication Date: 03/18/2020 Effective Date: 06/18/2020 Rev. 7
Appendix 1 − Application of New Installation and Design Requirements to Qualified Delayed Applicant-Installed Work Page 1 of 2
This appendix clarifies how to apply various new installation and design requirements to qualified delayed applicant-installed gas projects, where the gas distribution main backbone and service stubs were installed and inspected, but the service completions have not been completed for many months or years.
Note: This does not apply to any “at-risk” projects.
The Company has encountered delayed applicant-installed projects (e.g., subdivisions) where the gas distribution main backbone and service stubs were installed and inspected, but the service completions have not been completed for many months or years, and the system has not been pressurized, energized, and accepted by the Company. These projects must meet the following criteria:
Job designs were previously approved by the Company.
Contracts were executed by the applicant with the Company for the project.
Company has inspected the work to date on the project.
Current installation and design requirements must be applied when a delayed project is actually pressurized and placed in service.
This appendix addresses the following new requirements:
Pipe locating requirements
One-inch diameter services
1000-foot maximum spacing between Electrolysis Test Stations (ETS)
Locating wire gauge requirements for plastic pipe installations
Pressure testing
Locating Requirements
A. Applicant installers are required to mark dead end gas mains, and gas service stubs as described in GDS A-90.2, and GDS A-90.3.
- One-inch services
CMC § 3.3. High relevance — show source text
= On Center.
a. Steel framing shall be minimum 33-ksi steel for 33-mil and 43-mil steel, and 50-ksi steel for 54-mil steel or thicker.
b. Where cladding is attached to wood structural panel sheathing only, fastening requirements shall be in accordance with Table R703.3.3. For brick veneer tie connections to
wood structural panels, refer to Table R703.8.4(2).
c. Screws shall comply with the requirements of ASTM C1513.
d. Foam sheathing shall have a minimum compressive strength of 15 psi in accordance with ASTM C578 or ASTM C1289.|For SI: 1 inch = 25.4 mm, 1 mil = 0.0254 mm, 1 pound per square foot = 0.0479 kPa, 1 pound per square inch = 6.895 kPa.
DR = Design Required.
o.c. = On Center.
a. Steel framing shall be minimum 33-ksi steel for 33-mil and 43-mil steel, and 50-ksi steel for 54-mil steel or thicker.
b. Where cladding is attached to wood structural panel sheathing only, fastening requirements shall be in accordance with Table R703.3.3. For brick veneer tie connections to
wood structural panels, refer to Table R703.8.4(2).
c. Screws shall comply with the requirements of ASTM C1513.
d. Foam sheathing shall have a minimum compressive strength of 15 psi in accordance with ASTM C578 or ASTM C1289.|For SI: 1 inch = 25.4 mm, 1 mil = 0.0254 mm, 1 pound per square foot = 0.0479 kPa, 1 pound per square inch = 6.895 kPa.
DR = Design Required.
o.c. = On Center.
a. Steel framing shall be minimum 33-ksi steel for 33-mil and 43-mil steel, and 50-ksi steel for 54-mil steel or thicker.
b. Where cladding is attached to wood structural panel sheathing only, fastening requirements shall be in accordance with Table R703.3.3. For brick veneer tie connections to
wood structural panels, refer to Table R703.8.4(2).
c. Screws shall comply with the requirements of ASTM C1513.
d. Foam sheathing shall have a minimum compressive strength of 15 psi in accordance with ASTM C578 or ASTM C1289.|R703.16.2 Furred cladding attachment. Where steel or wood furring is used to attach cladding over foam sheathing, furring minimum fastening requirements to support the cladding weight shall be as specified in Table R703.16.2. Where placed horizontally, wood furring shall be preservative-treated wood in accordance with Section R304.1 or naturally durable wood and fasteners shall be corrosion resistant in accordance with Section R304.3. Steel furring shall have a minimum G60 galvanized coating.
|TABLE R703.16.2—FURRING MINIMUM FASTENING REQUIREMENTS FOR
APPLICATION OVER FOAM PLASTIC SHEATHING TO SUPPORT CLADDINGCMC § 3.5. Medium relevance — show source text
3.5. Fault Line Crossings
A. Avoid installing mains and services across fault lines whenever possible. Whenever it is necessary to install a main or service across a fault line, consider fault creep when designing the crossing and include appropriate precautions, such as the following:
(1) Installing shut off valves on the main on either side of the crossing.
(2) Minimizing the use of fittings and bends in the vicinity of the crossing.
(3) Using a large−diameter plastic casing to absorb deflection caused by fault
creep.
B. Contact distribution integrity management program (DIMP) personnel for assistance in designing fault line crossings.
4 Construction Methods
4.1. PE Joining Methods
A. The preferred joining methods for each size pipe is shown in Table 1.
Table 1. PE Pipe - Joining Methods
Pipe/Tubing Size or Connection
TypePreferred Joining Methods1 Alternate Joining Methods2 ½″ CTS‒1¼″ Iron Pipe Size (IPS) Electrofusion, Socket Fusion Mechanical 2″ IPS Electrofusion, Socket Fusion, Butt Fusion Mechanical 3″‒8″ IPS Butt Fusion Electrofusion Saddle Electrofusion, Heat Iron Saddle Bolt-On Saddle - Heat iron saddle, socket, and butt fusion are not permitted on Aldyl-A pipe.
- Consider for repairs and tie-in connections.
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Page 7 of 17
Polyethylene Gas Distribution System Design A-90
Publication Date: 03/18/2020 Effective Date: 06/18/2020 Rev. 7
4.1 (continued)
B. A 2″ mechanical stab type fitting may only be used for main or service PE pipeline repair, riser replacement, hot tie-in connections (a connection between a new or replaced section of pipeline and an existing pipeline already pressurized with natural gas), and main or service capping (end cap only).
4.2. Typical Direct-Burial Plastic Main and Service Installation
A. Unless approved by engineering personnel do not install direct-buried plastic pipe under structures subject to settlement that could cause damage to the pipeline, such as: retaining structures, walls or footings, or adjacent to pile.
B. Do not install direct-buried plastic pipe in unpaved areas where substantial wheel or equipment loading may damage the pipe, unless approved by the appropriate senior gas distribution engineer .
C. A warning tape must be installed in direct-burial installations per GDS L-16, “Gas Pipeline Underground Warning Tape.”
4.3. Directional Changes
A. Changes in pipe direction must be made with elbows, or tee fittings at street intersections (as illustrated in Attachment 1, “Illustration of a Direct Burial Main and Service Installation”). Roping may be used for directional changes at other locations, when necessary.
B. Bends in roped PE pipe must be installed in the trench with a radius greater than the minimum recommended radius (Table 2). All bends must have a radius greater than: 20 times the pipe diameter for SDR 7 and 9, and 25 times the pipe diameter for SDR 10, 11, 11.5 and 13.5.
CMC § 93.3. Medium relevance — show source text
- One-inch services
A. The Company will accept previously-installed ½″ services, and ½″ service stubs installed prior to May 1, 2010, if those services and stubs have the capacity to support the current customer loads.
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©2020 Pacific Gas and Electric Company. All rights reserved.
PG&E Internal Information
Polyethylene Gas Distribution System Design A-90
Publication Date: 03/18/2020 Effective Date: 06/18/2020 Rev. 7
Appendix 1 − Application of New Installation and Design Requirements to Qualified Delayed Applicant Installed Work Page 2 of 2
B. The gas service stub must be at least 1″ in diameter if any of the following conditions exists:
- Customer gas load conditions require a larger size gas service. Forexample, 1″ EFVs and services are required for service lengths of 122′ or longer, per GDS A-93.3. Note that GDS A-93.3 also directs that EFVs are not to be installed on stub completions
- Branch services - Changed or new customer gas loads that exceed the capacity of thepreviously designed service
1000′ maximum spacing between ETS boxes
- Applicant installers are required to install ETS boxes every 1000′(or closer) in accordance with GDS A-90.2.
Locating wire gauge requirements for plastic pipe installations
- The Company will accept 14-gauge locating wire on existing plastic pipe service installations, installed prior to August 1, 2009, as long as the wire passes continuity tests. Applicant installers are not required to replace existing 14-gauge wire (that pass continuity tests) with 10-gauge on plastic services, and service stubs that have already been installed. However, all new plastic services and service stubs must be installed with 10-gauge wire in accordance with GDS A-90.2 and GDS A-90.3.
Pressure Test
- Main and stubs are required to be tested per GDS A-34.
PG&E Internal Information “PG&E” refers to Pacific Gas and Electric Company, a subsidiary of PG&E Corporation.
©2020 Pacific Gas and Electric Company. All rights reserved.
Page 17 of 17
GAS DESIGN STANDARD
INSTALLING AND MAINTAINING A
POLYETHYLENE (PE) GAS DISTRIBUTION SYSTEM
A-93.1
Publication Date: 12/15/2021 Effective Date: 03/01/2022 Rev. 11
Purpose and Scope
This gas design standard (GDS) provides requirements for installing and maintaining the Pacific Gas and Electric Company (PG&E or Company) polyethylene (PE) gas distribution system.
1 General Information
1.1. Joining PE
A. For approved joining methods, approved materials, and qualification requirements, see Appendix A.
B. Standard heat iron fusions are not allowed on Aldyl-A material. Use only electrofusion or mechanical fittings with Aldyl-A material.
CMC § 605.3.2 Medium relevance — show source text
Listed solvent cement that complies with ASTM F493 and that does not require the use of primers, yellow in color, shall be permitted to join pipe that comply with ASTM F2855 and fittings that comply with ASTM D2846, [1] ⁄ 2 of an inch (15 mm) through 2 inches (50 mm) in diameter. Apply primer where required inside the fitting and to the depth of the fitting on pipe. Apply liberal coat of cement to the outside surface of pipe to depth of fitting and inside of fitting. Place pipe inside fitting to forcefully bottom the pipe in the socket and hold together until joint is set. 605.3.2 Mechanical Joints. Mechanical joints shall include flanged, grooved, and push fit fittings. 605.3.2.1 Push Fit Fittings. Removable and nonremovable push fit fittings that employ a quick assembly push fit connector shall comply with ASSE 1061.
605.4 Ductile Iron Pipe and Joints. Ductile iron pipe and fitting joining methods shall be installed in accordance with the manufacturer’s installation instructions and shall comply with Section 605.4.1 or Section 605.4.2. 605.4.1 Mechanical Joints. Mechanical joints for ductile iron pipe and fittings shall consist of a bell that is cast integrally with the pipe or fitting and provided with an exterior flange having bolt holes and a socket with annular recesses for the sealing gasket and the plain end of the pipe or fitting. The elastomeric gasket shall comply with AWWA C111. Lubricant recommended for potable water application by the pipe manufacturer shall be applied to the gasket and plain end of the pipe. 605.4.2 Push-On Joints. Push-on joints for ductile iron pipe and fittings shall consist of a single elastomeric gasket that shall be assembled by positioning the elastomeric gasket in an annular recess in the pipe or fitting socket and forcing the plain end of the pipe or fitting into the socket. The plain end shall compress the elastomeric gasket to form a positive seal and shall be designed so that the elastomeric gasket shall be locked in place against displacement. The elastomeric gasket shall comply with AWWA C111. Lubricant recommended for potable water application by the pipe manufacturer shall be applied to the gasket and plain end of the pipe.
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WATER SUPPLY AND DISTRIBUTION
605.5 Galvanized Steel Pipe and Joints. Galvanized steel pipe and fitting joining methods shall be installed in accordance with the manufacturer’s installation instructions and shall comply with Section 605.5.1 or Section 605.5.2.
605.5.1 Mechanical Joints. Mechanical joints shall be made with an approved and listed elastomeric gasket.
CMC § 4110P-03 Medium relevance — show source text
Gas Design Standard F-80, “Meter Valves”
Gas Design Standard F-90, “Polyethylene (PE) Valves”
Gas Design Standard J-15, “Gas Meter Locations”
Gas Design Standard J-16, “Gas Meter Room”
Gas Design Standard K-40, “Plastic Valve Box for 3/4” - 4” Valves”
Gas Design Standard L-16, “Gas Pipeline Underground Warning Tape”
Gas Design Standard O-96, “Insulating Metal Gas Lines from Walls"
Utility Manual TD-4180M, Gas Transmission and Distribution Manual - Corrosion Control Volume.
Utility Procedure TD-4110P-03-F01, “Leak Repair, Inspection, and Gas Quarterly Incident Report”
Utility Procedure TD-4634P-01, “Polyethylene Service Splitting”
Utility Standard GS I.S. 463-4, “Cover and Clearance Requirements for Transmission Lines, Mains and Service Lines”
Utility Standard S0470, “Design and Construction of Gas Distribution Facilities”
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©2020 Pacific Gas and Electric Company. All rights reserved.
PG&E Internal Information
Polyethylene Gas Distribution System Design A-90
Publication Date: 03/18/2020 Effective Date: 06/18/2020 Rev. 7
References (continued)
Utility Standard S5453, “Joint Trench”
Utility Standard TD-4801S, “Service Replacement Criteria”
Work Procedure WP4170-02, “Squeezing Polyethylene (PE) pipe”
Appendices
Appendix 1, “Application of New Installation and Design Requirements to Qualified Delayed
” Applicant-Installed Work
Attachments
Attachment 1, “Illustration of a Direct Burial Main and Service Installation”
Revision Notes
Revision 7 has the following changes:
Incorporated content from Utility Bulletin TD-A-93.1B-001, “Mechanical Fittings Connections Use Clarification” to clarify what connections mechanical fittings can be used on.
Added guidance for fully replaced services, 1″ CTS is the preferred minimum pipe size but to consider ½″ pipe when inserting or splitting if adequate for service load and length.
Updated Table 1 to clarify preferred joining methods and alternate joining methods for PE pipe.
Clarified definition of hot tie-in for 2″ stab fittings.
Added guidance on parallel main installations for capacity jobs.
Updated guidance on methods used to vent casings on risers.
Removed old plastic pipe stamp and referenced GDS A-34 for leak test stamp requirements.
Removed table for bend radius in riser casing, as Table 2 will be adequate table to use for that scenario.
Asset Type: Distribution Services
Function: Design, Construction, and Maintenance
Document Contact: Gas Design Standard Responsibility List
PG&E Internal Information “PG&E” refers to Pacific Gas and Electric Company, a subsidiary of PG&E Corporation.
©2020 Pacific Gas and Electric Company. All rights reserved.
Page 15 of 17
Polyethylene Gas Distribution System Design A-90
Publication Date: 03/18/2020 Effective Date: 06/18/2020 Rev. 7
CMC § 1801.1 Medium relevance — show source text
Materials for piping and tubing must meet the working temperature and pressure of the system. Furthermore, materials must be compatible with the transfer medium to prevent deformation, bursting, or any chemical action between the material and the transfer medium. Approved materials for indoor piping, fittings, and accessories that are a part of a groundwater system as well as the allowable joining methods for piping or tubing are provided for application and enforcement purposes.
Chapter 18 Referenced Standards. Chapter 18 provides two comprehensive tables with referenced standards. The standards listed in Table 1801.1 are applied as indicated in the applicable reference section(s). A list of additional approved standards, publications, practices, and guides that are not referenced in specific sections appear in Table 1801.2.
Referenced standards set forth specific details of accepted practices, materials specifications, or test methods in many specialized applications. Standards provide an efficient method of conveying complex information and specifications on the performance requirements for materials, products, systems, application, and installation. The manner and purpose for a standard’s use and, in turn, code compliance, must be definitive in all references to the standard. If the standard is intended to be a requirement for judging code compliance, the code must state its intent for use. The standard should adequately address a defined need and at the same time specify the minimum performance requirements, technical characteristics and methods of testing, and required test results.
The referenced standards tables are organized in a manner that makes it easy to find specific standards in alphabetical order, and by acronym of the publishing agency of the standard. The tables list the title of the standard, the edition, and any addenda. Contact information for each publishing agency is provided at the end of the chapter.
Appendix A Residential Plans Examiner Review Form for HVAC System Design. A residential plans examiner review form is located in this appendix as an example to assist users in identifying whether the HVAC system has followed the approved procedures for system design (loads, equipment, and ducts).
Appendix B Procedures to be Followed to Place Gas Equipment in Operation. Appendix B provides requirements for the procedures that apply after an appliance is installed in place, piped, and connected to its venting system. The requirements include adjusting the burner input, air adjustments, verifying operation of safety shutoffs, automatic ignition, and protective devices, checking draft for vent-connected appliances, and operating instructions.
Appendix C Installation and Testing of Oil (Liquid) Fuel-Fired Equipment. Appendix C governs the installation, testing, or repair of oil or liquid fuel-burning equipment used in buildings or structures and equipment.
Appendix D Fuel Supply: Manufactured/Mobile Home Parks and Recreational Vehicle Parks. The provisions of this appendix apply to the fuel gas piping systems of mobile home and recreational vehicle parks. These provisions also apply to the use, maintenance, and installation for supplying fuel gas for accessory buildings or structures, and building components.
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FORMAT OF THE UNIFORM MECHANICAL CODE
Appendix E Sustainable Practices. This appendix provides a comprehensive set of technically sound provisions that encourage sustainable practices and works toward improving the design and construction of mechanical systems that result in a positive long-term environmental impact. Environmental sustainability is important because it involves natural resources that human beings need for economic or manufactured capital. Their sustainability is defined by their reliance
CMC § 90.3. Medium relevance — show source text
D. To make sharp turns or offsets (smaller than the minimum bend radius in Table 2), install full-opening heat fusion fittings per GDS B-90, or electrofusion fittings per GDS B-90.3.
PG&E Internal Information “PG&E” refers to Pacific Gas and Electric Company, a subsidiary of PG&E Corporation.
©2020 Pacific Gas and Electric Company. All rights reserved.
Page 5 of 17
Polyethylene Gas Distribution System Design A-90
Publication Date: 03/18/2020 Effective Date: 06/18/2020 Rev. 7
3.3 (continued)
Figure 1. Typical Subdivision Design – Infill
E. Place the gas facilities in the distribution trench per Utility Standard S5453, “Joint Trench.” Placement in a public utility easement (PUE) is preferred.
Figure 2. Typical Subdivision Design − End of System Growth
Page 6 of 17 “PG&E” refers to Pacific Gas and Electric Company, a subsidiary of PG&E Corporation.
©2020 Pacific Gas and Electric Company. All rights reserved.
PG&E Internal Information
Polyethylene Gas Distribution System Design A-90
Publication Date: 03/18/2020 Effective Date: 06/18/2020 Rev. 7
3.3 (continued)
F. A subdivision design for end of system growth is shown in Figure 2. Extend the distribution main along the proposed road to provide a back-tie to the proposed development.
3.4. Branch Services
A. Branch services must be designed and installed as outlined in GDS A-42, “Standard Branch Service Installation.”
B. Branching may be used to provide service to no more than two buildings. The meter installations must be located on the adjacent sides of the two buildings served. Where a branch-service installation is justified, a separate location for the gas meter and electric meter is permissible, if necessary.
3.5. Fault Line Crossings
A. Avoid installing mains and services across fault lines whenever possible. Whenever it is necessary to install a main or service across a fault line, consider fault creep when designing the crossing and include appropriate precautions, such as the following:
(1) Installing shut off valves on the main on either side of the crossing.
(2) Minimizing the use of fittings and bends in the vicinity of the crossing.
(3) Using a large−diameter plastic casing to absorb deflection caused by fault
creep.
B. Contact distribution integrity management program (DIMP) personnel for assistance in designing fault line crossings.
4 Construction Methods
4.1. PE Joining Methods
A. The preferred joining methods for each size pipe is shown in Table 1.
Table 1. PE Pipe - Joining Methods
Pipe/Tubing Size or Connection
TypePreferred Joining Methods1 Alternate Joining Methods2 ½″ CTS‒1¼″ Iron Pipe Size (IPS) Electrofusion, Socket Fusion Mechanical 2″ IPS Electrofusion, Socket Fusion, Butt Fusion Mechanical 3″‒8″ IPS Butt Fusion Electrofusion Saddle Electrofusion, Heat Iron Saddle Bolt-On Saddle - Heat iron saddle, socket, and butt fusion are not permitted on Aldyl-A pipe.
- Consider for repairs and tie-in connections.
California Mechanical Code Medium relevance — show source text
A. Mechanical couplings and newly approved Shur−lock II couplers (See Figure 31 and Table 24 on Page 14 ) can be used for joining HDPE to HDPE conduits as well as HDPE to PVC conduits.
Caution: When pulling conduit(s) in boring applications, be certain to cut the conduits allowing sufficient extra length for the conduit to relax. It may take as long as 72 hours for an excessively stretched conduit to fully relax.
Caution: Do not use Snap-N-Stac Combo Spacers in concrete encased application.
Conduit shown on Table 20 through Table 23 (flexible conduit) on Page 11 through Page 14 are for use in areas with minor soil settlement issues, and for large radius sweeps or re-routes.
Backfill containing large rock, paving material, cinders, large amounts of sharply angular substance, or corrosive material must not be placed in excavations where such material may damage conduits, prevent adequate compaction of the fill, or contribute to corrosion of the conduits. Soil compaction must meet PG&E’s and any applicable federal, state, county, and local requirements. PG&E specific soil compaction requirements are as follows:
A. Trenches that run across or along public roads and streets in the franchise areas must have soil compacted to a minimum of 95% density.
B. Trenches that run across private properties and in all other areas must have soil compacted to a minimum of 90% density.
C. A compaction test report may be required by PG&E. This report must include the testing company information: Name, Address, Contact information.
References Location Document
Minimum Requirements for the Design and Installation of Conduit and Insulated Cable . . . . . . . UG-1: Cable/Greenbook . . . . . . . . . . . . . . 038193 Methods and Requirements for Installing Residential Underground Electric Services 0−600 V to Customer-Owned Facilities . . . . . . . . . . . . . . . . . . . UG-1: Services/Greenbook . . . . . . . . . . . .
CMC § 3.2 Medium relevance — show source text
Metal insert fittings shall comply with ASTM F1974. Crimp insert fittings shall be joined to the pipe by placing the copper crimp ring around the outer circumference of the pipe, forcing the pipe material into the space formed by the ribs on the fitting until the pipe contacts the shoulder of the fitting. The crimp ring shall then be positioned on the pipe so the edge of the crimp ring is [1] ⁄ 8 of an inch (3.2 mm) to [1] ⁄ 4 of an inch (6.4 mm) from the end of the pipe. The jaws of the crimping tool shall be centered over the crimp ring and tool perpendicular to the barb. The jaws shall be closed around the crimp ring and shall not be crimped more than once. 605.7.1.1 Compression Joints. Compression joints for PE-AL-PE pipe or tubing and fittings shall be joined through the compression of a split ring, by a compression nut around the circumference of the pipe. The compression nut and split ring shall be placed around the pipe. The ribbed end of the fitting shall be inserted into the pipe until the pipe contacts the shoulder of the fitting. Position and compress the split ring by tightening the compression nut onto the insert fitting. 605.8 PE-RT. Polyethylene of raised temperature (PE-RT) tubing and fitting joining methods and shall comply with Section 605.8.1.
605.8.1 Mechanical Joints. Fittings for PE-RT tubing shall comply with the applicable standards listed in Table 604.1. Mechanical joints for PE-RT tubing shall be installed in accordance with the manufacturer’s instal lation instructions.
605.9 PEX Plastic Tubing and Joints. PEX plastic tubing and fitting joining methods shall be installed in accordance with the manufacturer’s installation instructions and shall comply with Section 605.9.1 through Section 605.9.3.
All PEX pipe installed in California must provide at least 30-day UV protection. [OSHPD 1, 1R, 2, 3, 4 & 5] Instal- lation and use of PEX tubing shall be in accordance with manufacturer’s standards. PEX piping shall not be used for any application that would result in noncompliance with any provisions of the California Building Standards Code. 605.9.1 Fittings. Fittings for PEX tubing shall comply with the applicable standards referenced in Table 604.1. PEX tubing that complies with ASTM F876 shall be marked with the applicable standard designation for the
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WATER SUPPLY AND DISTRIBUTION
CMC § 4.1 Medium relevance — show source text
2 Reference Publications
This Standard refers to the following publications, and where such reference is made, it shall be to the current edition of those publications, including all amendments published thereto.
ASTM International
ASTM D3261
Standard Specification for Butt Heat Fusion Polyethylene (PE) Plastic Fittings for Polyethylene (PE) Plastic Pipe and Tubing
ASTM F714
Standard Specification for Polyethylene (PE) Plastic Pipe (DR-PR) Based on Outside Diameter
ASTM F894
Standard Specification for Polyethylene (PE) Large Diameter Profile Wall Sewer and Drain Pipe
ASTM F1055
Standard Specification for Electrofusion Type Polyethylene Fittings for Outside Diameter Controlled Polyethylene and Crosslinked Polyethylene (PEX) Pipe and Tubing
ASTM F2620
Standard Practice for Heat Fusion Joining of Polyethylene Pipe and Fittings
3 Abbreviations
The following abbreviations apply in this Standard:
PE — Polyethylene
HDPE — High Density Polyethylene
4 General
4.1 Product Requirements
Polyethylene (PE) sewer pipe or tubing and fitting joining methods shall be installed in accordance
2025 CALIFORNIA PLUMBING CODE 451
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IS 26
with the manufacturer’s installation instructions and comply with ASTM F714, ASTM F894 the applicable nationally recognized standard.
4.2 HDPE Materials
HDPE Extra High Molecular Weight 3408 SDR 17 Pipe Socket-Type PE Fittings for Outside Diameter Controlled.
Note: The HDPE 3408 SDR 17 pipe used in this process was selected because of its ability to retain its circular shape even when bent on a 1.2 m (4 ft) radius during and after installation. 4.3 Protection of Pipe
Pipe shall be stored in a way to protect it from mechanical damage (slitting, puncturing, etc.). It shall be stored under cover to keep it clean and avoid long term exposure to sunlight. Exposure to sunlight during normal construction periods is acceptable. 4.4 Joining Methods
PE joints shall be made in accordance with the manufacturer’s installation instructions. PE pipe shall be joined to other pipe materials by an approved listed adapter or transition fittings listed for the specific transition intended.
4.4.1 Butt-Fusion Joints [2024 UPC 705.5.1.1]
Butt-fusion joints for PE pipe shall be installed in accordance with ASTM F2620 and shall be made by heating the prepared ends of two pipes, pipe and fitting, or two fittings by holding ends against a heated element. The heated element shall be removed when the required melt or times are obtained, and heated ends shall be placed together with applied force. Do not disturb the joint until cooled to ambient temper ature.
4.4.2 Electro-Fusion Joints [2024 UPC 705.5.1.2]
CMC § 605.8 Medium relevance — show source text
Position and compress the split ring by tightening the compression nut onto the insert fitting. 605.8 PE-RT. Polyethylene of raised temperature (PE-RT) tubing and fitting joining methods and shall comply with Section 605.8.1.
605.8.1 Mechanical Joints. Fittings for PE-RT tubing shall comply with the applicable standards listed in Table 604.1. Mechanical joints for PE-RT tubing shall be installed in accordance with the manufacturer’s instal lation instructions.
605.9 PEX Plastic Tubing and Joints. PEX plastic tubing and fitting joining methods shall be installed in accordance with the manufacturer’s installation instructions and shall comply with Section 605.9.1 through Section 605.9.3.
All PEX pipe installed in California must provide at least 30-day UV protection. [OSHPD 1, 1R, 2, 3, 4 & 5] Instal- lation and use of PEX tubing shall be in accordance with manufacturer’s standards. PEX piping shall not be used for any application that would result in noncompliance with any provisions of the California Building Standards Code. 605.9.1 Fittings. Fittings for PEX tubing shall comply with the applicable standards referenced in Table 604.1. PEX tubing that complies with ASTM F876 shall be marked with the applicable standard designation for the
2025 CALIFORNIA PLUMBING CODE 151
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WATER SUPPLY AND DISTRIBUTION
fittings, specified by the tubing manufacturer for use with the tubing. Brass fittings used with PEX tubing shall meet or exceed NSF/ANSI 14 standards to prevent dezincifi- cation and stress crack corrosion. [OSHPD 1, 1R, 2, 3, 4 & 5] Installation and use of PEX tubing shall be in accordance with manufacturer’s standards. PEX piping shall not be used for any application that would result in noncompliance with any provisions of the California Building Standards Code. 605.9.2 Mechanical Joints. Mechanical joints shall be installed in accordance with the manufacturer’s instal lation instructions.
605.9.3 Push Fit Fittings. Removable and nonremovable push fit fittings that employ a quick assembly push fit connector shall comply with ASSE 1061. 605.10 PEX-AL-PEX Plastic Tubing and Joints. PEXAL-PEX plastic pipe or tubing and fitting joining methods shall be installed in accordance with the manufacturer’s installation instructions and shall comply with Section 605.10.1 and Section 605.10.1.1.
[BSC, DSA-SS, HCD 1 & HCD 2] PEX-AL-PEX is not adopted for use in potable water supply and distribution sys-
tems.
California Mechanical Code Medium relevance — show source text
(See Table 1 on Page 3 for
approved list of wood pole suppliers.)| |3|Meter Socket, Main Service Switch| |4|Conduit, Service (see Note 14 on Page 5)| |5|Conduit, Load Side (see Note 14 on Page 5)| |6
|Conduit Fitting, Threaded, With Cover and Gasket
| |7 ~~1 ~~
|Covering, PVC Conduit, or PVC Moulding (see Page 9)
| |8 ~~1 ~~|Wood Block (4” x 4” x 6” or two 2” x 4” x 6” nailed together)| |9|Service Head| |10|Service Knob| |11|Wire, Insulated (size as required) (18” minimum extension from service head)| |12|Bolt, Machine, 5/8 or 3/4, (as required), Galvanized| |13|Washer, Curved, 3” x 3” (for 5/8” Bolt) or 4” x 4” (for 3/4” Bolt), Galvanized| |14|Guy Hook or Guy Pole Plate and Thimble Assembly| |15|Guy Strand Cable, 7/32” or 1/4“ Minimum Galvanized Steel or Equivalent| |16|Insulator, Guy Strain (10,000 lbs. minimum)| |17|Guy Grip, Preform, (as required)| |18|Anchor Rod, 5/8” x 6’ 0” Minimum, and Fittings (as required)| |19|Anchor, 16” Cross Plate, or 8” Expanding| |20|Guy Marker| |21|Push Brace, 2” x 4” Minimum Timber (securely bolted to pole). See Figure 14 on Page 12.| |22
|Grounding by Customer (see Pages 8 and 10)|1 Omit conduit covering, Item 7, and wood block, Item 8, on a metal pole or on a wood pole with plastic conduit (see Note 15 on Page 5). Exception : The wood block is required for a wood pole with plastic conduit when the service head is metallic and the neutral service entrance conductor is uninsulated (see Note 15 on Page 5).
Table 6 Materials to Be Furnished and Installed by PG&E
Items Description Document 23 Vertical Construction − 24 Spool and Clevis 022439 25 Meter, Watthour (as required) − 26 Service Wire (as required) 059626 27 Insulator, for Service Wire (as required) 025202 28 Connectors, Service Sleeve (as required) 028852 29 Preformed Grip, Dead-End (as required) 028851 Rev. #20: 3/25/2022 025055 Page 7 of 17
OH: Services Greenbook Requirements for Customer-Owned Poles EMWP
Temporary Installations
Notes
Locate the guy in line with the service drop. The guy must be maintained taut.
Grounding and bonding, by the customer, must be in accordance with NEC and local ordinances, (see Note 20 on Page 5). The ground rod must be located no less than 12 inches from the pole surface.
Frequently asked questions
What if the manufacturer and a referenced ASTM standard conflict?
Follow the adoptive code hierarchy and the authority having jurisdiction (AHJ). The CMC requires compliance with the code and referenced standards; when in doubt the AHJ enforces the code. Confirm with the AHJ and retain the manufacturer’s documentation.
Are mechanical couplings allowed on all PE sizes?
Not always. Allowed methods depend on pipe material, size and product listing. For many PE sizes mechanical may be an alternate or repair method only; larger diameters commonly require butt-fusion. Check the product listing and referenced standards.
Do I need to document fusion cycles and operator details?
Yes — accepted practice (and AHJs) expect fusion records for critical joints: fitting ID, fusion cycle, operator, and any QA tests. The code points to manufacturer/standard requirements for installation and quality assurance.
Is cooling time important for heat-fusion joints?
Yes. The plumbing references explicitly state do not disturb the joint until cooled to ambient temperature — disturbing a joint too early can weaken it.
Are utility rules (e.g., PG&E Greenbook) authoritative for code compliance?
Utility/industry standards (like PG&E) are not the CMC but are commonly used engineering/operational requirements and provide important practical restrictions (for example, certain methods prohibited on specific PE compounds). Use them in conjunction with the code and the AHJ’s direction.
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