CMC · California Mechanical Code

What are the rules for appliance connectors, tee (sediment) traps and accessory installations?

If an appliance lacks a built‑in sediment trap you must install a tee‑type trap (or an approved equivalent) immediately downstream of its shutoff and as close to the appliance inlet as practical; arrange piping and accessories so they do not block inspection or servicing; LP‑Gas installations must follow NFPA 58. **§ 1312.9**, **§ 1312.10**, **§ 1312.11**.

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Last reviewed: July 6, 2026

What the code requires — 2-4 sentences

The California Mechanical Code requires that when an appliance does not include an internal sediment trap, a trap (commonly a tee fitting with a capped nipple) must be installed immediately downstream of the appliance shutoff valve and as close to the appliance inlet as practical. This same portion of the code requires that piping and accessory installations be arranged so they do not interfere with inspection, maintenance, or servicing. For liquefied petroleum gas (LP‑Gas) facilities and piping the CMC defers to NFPA 58. See § 1312.9, § 1312.10, and § 1312.11.

The single most important rule: install a sediment trap (tee with capped nipple or an approved equivalent) immediately downstream of the appliance shutoff valve and as close to the appliance inlet as practical. § 1312.9.

Requirements in detail

Sediment traps (tee traps)

What’s required: Where the appliance does not include a built‑in trap, install a sediment trap downstream of the appliance shutoff valve and as close to the inlet of the appliance as practical. § 1312.9.
Acceptable form: The trap shall be either a tee fitting with a capped nipple in the bottom outlet (the usual “tee trap” configuration) or another device recognized as an effective sediment trap. § 1312.9.
Exempt appliances: Illuminating appliances, gas ranges, clothes dryers, decorative appliances for installation in vented fireplaces, gas fireplaces, and outdoor cooking appliances are specifically not required to have the trap. § 1312.9.

Decision-relevant dimensions / values

Decision item	What the code requires	Code Reference
Location of trap relative to shutoff	Downstream of the appliance shutoff valve and as close to inlet as practical	§ 1312.9
Acceptable trap configuration	Tee fitting with a capped nipple in bottom outlet, or other approved device	§ 1312.9
Appliances exempt from trap requirement	Illuminating appliances, gas ranges, clothes dryers, decorative vented‑fireplace appliances, gas fireplaces, outdoor cooking appliances	§ 1312.9
Visual guidance	Figure showing method of installing a tee fitting sediment trap (see CMC figure)	FIGURE 1312.9 (illustration referenced in § 1312.9)

Piping and accessory installation (access for service)

Requirement: Piping shall be installed in a manner not to interfere with inspection, maintenance, or servicing of the appliances. That applies to locations of connectors, valves, traps, and other accessories. § 1312.10.
Practical implications:
- Leave clear access to the appliance inlet, shutoff valve, and the sediment trap so they can be inspected and cleaned.
- Avoid routing piping or placing devices so that a disconnected appliance blocks access to its valve or trap.

Decision item	What the code requires	Code Reference
Interference with service	Install piping/accessories so they do not interfere with inspection, maintenance, servicing	§ 1312.10
Typical design check	Can technician get to the shutoff, trap, and connector without removing major finishes or moving the appliance? — If no, redesign	§ 1312.10

LP‑Gas facilities and piping

Requirement: Liquefied Petroleum Gas (LP‑Gas) facilities and piping shall comply with NFPA 58. The CMC does not restate NFPA 58 requirements but mandates compliance. § 1312.11.

Decision item	What the code requires	Code Reference
LP‑Gas rules	LP‑Gas facilities and piping must comply with NFPA 58 (see NFPA 58 for details)	§ 1312.11

Exceptions & special cases

The code expressly exempts the following appliances from the sediment‑trap requirement: illuminating appliances, gas ranges, clothes dryers, decorative appliances for installation in vented fireplaces, gas fireplaces, and outdoor cooking appliances. § 1312.9.
The requirement allows alternatives to the tee trap if the alternative is recognized as an effective sediment trap (i.e., approved devices or listings). § 1312.9.
For LP‑Gas installations the CMC delegates to NFPA 58; detailed LP‑Gas design/installation requirements (tank placement, piping materials, regulator arrangements, etc.) are found in NFPA 58 rather than in these CMC sections. § 1312.11.

If you need the specific NFPA 58 text or provisions (for example: clearances, tank location, or component labeling), those are not reproduced here and must be consulted directly in NFPA 58 as required by § 1312.11.

Common mistakes

Placing the sediment trap far away from the appliance inlet. The trap must be downstream of the shutoff valve and as close to the inlet as practical—not tucked away several feet down the line. § 1312.9.
Using a non‑approved trap configuration (e.g., horizontal clogged pockets that cannot be cleaned) instead of a tee with a capped nipple or an approved equivalent. § 1312.9.
Routing piping or accessories so they obstruct access to the shutoff, connector, or trap (violates the installation/access requirement). § 1312.10.
Assuming LP‑Gas is covered by the general gas rules—LP‑Gas installations must comply with NFPA 58; don’t rely solely on these sections for LP‑Gas specifics. § 1312.11.

Worked example

Scenario: You are installing a natural‑gas tank‑type water heater that does not have an internal sediment trap. The water‑heater inlet stub and the appliance shutoff valve are mounted on the sheet‑metal flue box.

Per § 1312.9, install a tee fitting with a capped nipple immediately downstream of the appliance shutoff valve and as close to the appliance inlet as practical (place the tee so its bottom leg with capped nipple is adjacent to the appliance inlet fitting). § 1312.9.
Arrange the piping so the trap and the shutoff valve remain accessible for inspection and cleaning—do not bury the trap behind the appliance or in a concealed chase, per § 1312.10.
If the appliance were an exempt type (for example a clothes dryer), the trap would not be required under § 1312.9.

Note: the code language uses “as close to the inlet of the appliance as practical” rather than a specific inch measurement—place the trap as near as practicable so it can intercept solids before they enter the appliance. § 1312.9.

Related provisions (select CMC sections to review)

§ 1312.6 Appliance shutoff valves and connections — location and servicing of shutoffs (see adjacent requirements to § 1312.9).
§ 1312.7 Quick‑disconnect devices — listing and valve requirements for quick disconnects.
§ 1312.8 Gas convenience outlets — requirements when using convenience outlets and listed appliance connectors.
§ 1310.9 Drips and sediment traps — additional context for drips and accessibility; references § 1312.9 for sediment trap installation.
FIGURE 1312.9 — Illustration of the tee‑fitting sediment trap method referenced by § 1312.9.

Code references

Grounded in the retrieved California Mechanical Code — click a citation to read the verbatim passage:

CMC § 9.6.2 High relevance — show source text
(2) The connector shall be of minimum length and shall not exceed 6 feet (1829 mm).

(3) The connector shall not be concealed and shall not extend from one room to another or pass through wall partitions, ceilings, or floors. [NFPA 54:9.6.2(1)] 1212.3.2 Outdoor. Where outdoor gas hose connectors are used to connect portable outdoor appliances, the connector shall be listed in accordance with CSA/ANSI

Z21.54/CSA 8.4 and installed in accordance with the following:

(1) An appliance shutoff valve, a listed quick-disconnect device, or a listed gas convenience outlet shall be installed where the connector is attached to the supply piping and in such a manner so as to prevent the accumulation of water or foreign matter.

(2) This connection shall be made only in the outdoor area where the appliance is to be used. [NFPA 54:9.6.2(2)]

(3) The connector length shall not exceed 15 feet (4572 mm).

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1212.8 Gas Convenience Outlets. Appliances shall be permitted to be connected to the building piping by means of a listed gas convenience outlet, in conjunction with a listed appliance connector, installed in accordance with the manufacturer’s installation instructions.

Gas convenience outlets shall be listed in accordance

with CSA/ANSI Z21.90/CSA 6.24 and installed in accor dance with the manufacturer’s installation instructions.

[NFPA 54:9.6.7]

1212.9 Sediment Trap. Where a sediment trap is not incorporated as a part of the appliance, a sediment trap shall be installed downstream of the appliance shutoff valve as close to the inlet of the appliance as practical at the time of appliance installation. The sediment trap shall be either a tee fitting with a capped nipple in the bottom outlet, as illustrated in Figure 1212.9, or another device recognized as an effective sediment trap. Illuminating appliances, gas ranges, clothes dryers, decorative appliances for installation in vented fireplaces, gas fireplaces, and outdoor cooking appliances shall not be required to be so equipped. [NFPA 54:9.6.8]

For SI units: 1 inch = 25.4 mm

FIGURE 1212.9

METHOD OF INSTALLING A TEE FITTING SEDIMENT TRAP

[NFPA 54: FIGURE 9.6.8]

1212.10 Installation of Piping. Piping shall be installed in a manner not to interfere with inspection, maintenance, or servicing of the appliances. [NFPA 54:9.6.9] 1212.11 Liquefied Petroleum Gas Facilities and Pip- ing. Liquefied petroleum gas facilities shall be in accordance with NFPA 58.

1213.0 Pressure Testing, Inspection, and Purging.

1213.1 Piping Installations. Prior to acceptance and initial operation, all piping installations shall be visually inspected and pressure tested to determine that the materials, design, fabrication, and installation practices comply with the requirements of this code. [NFPA 54:8.1.1.1]
CMC § 1312.7 High relevance — show source text
1312.7 Quick-Disconnect Devices. Quick-disconnect devices used to connect appliances to the building piping shall be listed in accordance with ANSI Z21.41/CSA 6.9.

Where installed indoors, an approved manual shutoff valve with a nondisplaceable valve member shall be installed upstream of the quick-disconnect device. [NFPA 54:9.6.6 – 9.6.6.2]

1312.8 Gas Convenience Outlets. Appliances shall be permitted to be connected to the building piping by means of a listed gas convenience outlet, in conjunction with a listed appliance connector, installed in accordance with the manufacturer’s installation instructions.

Gas convenience outlets shall be listed in accordance

with CSA/ANSI Z21.90/CSA 6.24 and installed in accor dance with the manufacturer’s installation instructions.

[NFPA 54:9.6.7]

1312.9 Sediment Trap. Where a sediment trap is not incorporated as a part of the appliance, a sediment trap shall be installed downstream of the appliance shutoff valve as close to the inlet of the appliance as practical at the time of appliance installation. The sediment trap shall be either a tee fitting with a capped nipple in the bottom outlet, as illustrated in Figure 1312.9, or another device recognized as an effective sediment trap. Illuminating appliances, gas ranges, clothes dryers, decorative appliances for installation in vented fireplaces, gas fireplaces, and outdoor cooking appliances shall not be required to be so equipped. [NFPA 54:9.6.8]

For SI units: 1 inch = 25.4 mm

FIGURE 1312.9

METHOD OF INSTALLING A TEE FITTING SEDIMENT TRAP

[NFPA 54: FIGURE 9.6.8]

1312.10 Installation of Piping. Piping shall be installed in a manner not to interfere with inspection, maintenance, or servicing of the appliances. [NFPA 54:9.6.9] 1312.11 Liquefied Petroleum Gas (LP-Gas) Facilities and Piping. Liquefied petroleum gas (LP-Gas) facilities shall comply with NFPA 58.

1313.0 Pressure Testing, Inspection, and Purging. 1313.1 Piping Installations. Prior to acceptance and initial operation, all piping installations shall be visually inspected and pressure tested to determine that the materials, design, fabrication, and installation practices comply with the requirements of this code. [NFPA 54:8.1.1.1] 1313.1.1 Inspection Requirements. Inspection shall consist of visual examination, during or after manufacture, fabrication, assembly, or pressure tests. [NFPA 54:8.1.1.2] 1313.1.2 Repairs and Additions. Where repairs or additions are made following the pressure test, the affected piping shall be tested. Minor repairs and additions are not required to be pressure tested, provided that the work is inspected and connections are tested with a noncorrosive leak-detecting fluid or other leak-detecting methods approved by the Authority Having Jurisdiction.

[NFPA 54:8.1.1.3]
CMC § 9.6.7 High relevance — show source text
[NFPA 54:9.6.7]

1212.9 Sediment Trap. Where a sediment trap is not incorporated as a part of the appliance, a sediment trap shall be installed downstream of the appliance shutoff valve as close to the inlet of the appliance as practical at the time of appliance installation. The sediment trap shall be either a tee fitting with a capped nipple in the bottom outlet, as illustrated in Figure 1212.9, or another device recognized as an effective sediment trap. Illuminating appliances, gas ranges, clothes dryers, decorative appliances for installation in vented fireplaces, gas fireplaces, and outdoor cooking appliances shall not be required to be so equipped. [NFPA 54:9.6.8]

For SI units: 1 inch = 25.4 mm

FIGURE 1212.9

METHOD OF INSTALLING A TEE FITTING SEDIMENT TRAP

[NFPA 54: FIGURE 9.6.8]

1212.10 Installation of Piping. Piping shall be installed in a manner not to interfere with inspection, maintenance, or servicing of the appliances. [NFPA 54:9.6.9] 1212.11 Liquefied Petroleum Gas Facilities and Pip- ing. Liquefied petroleum gas facilities shall be in accordance with NFPA 58.

1213.0 Pressure Testing, Inspection, and Purging.

1213.1 Piping Installations. Prior to acceptance and initial operation, all piping installations shall be visually inspected and pressure tested to determine that the materials, design, fabrication, and installation practices comply with the requirements of this code. [NFPA 54:8.1.1.1]

1213.1.1 Inspection Requirements. Inspection shall consist of visual examination, during or after manufacture, fabrication, assembly, or pressure tests. [NFPA 54:8.1.1.2]

1213.1.2 Repairs and Additions. Where repairs or additions are made following the pressure test, the affected piping shall be tested. Minor repairs and additions are not required to be pressure tested, provided that the work is inspected and connections are tested with a noncorrosive leak-detecting fluid or other leak-detecting methods approved by the Authority Having Jurisdiction.

[NFPA 54:8.1.1.3]

1213.1.3 New Branches. Where new branches are installed to new appliance(s), only the newly installed branch(es) shall be required to be pressure tested. Connections between the new piping and the existing piping shall be tested with a noncorrosive leak-detecting fluid or approved leak-detecting methods. [NFPA 54:8.1.1.4] 1213.1.4 Piping System. A piping system shall be tested as a complete unit or in sections. Under no circumstances shall a valve in a line be used as a bulkhead between gas in one section of the piping system and test medium in an adjacent section, unless a double block and bleed valve system is installed. A valve shall not be subjected to the test pressure unless it can be determined that the valve, including the valve closing mechanism, is designed to safely withstand the pressure. [NFPA 54:8.1.1.5] **1213.1.5 Regulators and Valves.
CMC § 25.4 High relevance — show source text
For SI units: 1 inch = 25.4 mm

FIGURE 1312.9

METHOD OF INSTALLING A TEE FITTING SEDIMENT TRAP

[NFPA 54: FIGURE 9.6.8]

1312.10 Installation of Piping. Piping shall be installed in a manner not to interfere with inspection, maintenance, or servicing of the appliances. [NFPA 54:9.6.9] 1312.11 Liquefied Petroleum Gas (LP-Gas) Facilities and Piping. Liquefied petroleum gas (LP-Gas) facilities shall comply with NFPA 58.

1313.0 Pressure Testing, Inspection, and Purging. 1313.1 Piping Installations. Prior to acceptance and initial operation, all piping installations shall be visually inspected and pressure tested to determine that the materials, design, fabrication, and installation practices comply with the requirements of this code. [NFPA 54:8.1.1.1] 1313.1.1 Inspection Requirements. Inspection shall consist of visual examination, during or after manufacture, fabrication, assembly, or pressure tests. [NFPA 54:8.1.1.2] 1313.1.2 Repairs and Additions. Where repairs or additions are made following the pressure test, the affected piping shall be tested. Minor repairs and additions are not required to be pressure tested, provided that the work is inspected and connections are tested with a noncorrosive leak-detecting fluid or other leak-detecting methods approved by the Authority Having Jurisdiction.

[NFPA 54:8.1.1.3]

1313.1.3 New Branches. Where new branches are installed to new appliance(s), only the newly installed branch(es) shall be required to be pressure tested. Connections between the new piping and the existing piping shall be tested with a noncorrosive leak-detecting fluid or approved leak-detecting methods. [NFPA 54:8.1.1.4] 1313.1.4 Piping System. A piping system shall be tested as a complete unit or in sections. Under no circumstances shall a valve in a line be used as a bulkhead between gas in one section of the piping system and test medium in an adjacent section, unless a double block and bleed valve sys

2025 CALIFORNIA MECHANICAL CODE 291

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tem is installed. A valve shall not be subjected to the test pressure unless it can be determined that the valve, including the valve-closing mechanism, is designed to safely withstand the pressure. [NFPA 54:8.1.1.5]

1313.1.5 Regulators and Valves. Regulator and valve assemblies fabricated independently of the piping system in which they are to be installed shall be permitted to be tested with inert gas or air at the time of fabrication. [NFPA 54:8.1.1.6]

1313.1.6 Test Medium. The test medium shall be air, nitrogen, carbon dioxide, or an inert gas. Oxygen shall not be used as a test medium. [NFPA 54:8.1.2]
CMC § 9.6.4.4 High relevance — show source text
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length and shall not extend from one room to another or pass through any walls, partitions, ceilings, or floors. Flexible connections shall not be used in any concealed location. They shall be protected against physical or thermal damage and shall be provided with gas shutoff valves in readily accessible locations in rigid piping upstream from the flexible connections. [NFPA 54:9.6.4.4]

1312.6 Appliance Shutoff Valves and Connections. Each appliance connected to a piping system shall have an accessible, approved manual shutoff valve with a nondisplaceable valve member, or a listed gas convenience outlet. Appliance shutoff valves and convenience outlets shall serve a single appliance only. [NFPA 54:9.6.5] The shutoff valve shall be located within 6 feet (1829 mm) of the appliance it serves. [NFPA 54:9.6.5.1] Where a connector is used, the valve shall be installed upstream of the connector. A union or flanged connection shall be provided downstream from the valve to permit removal of appliance controls. [NFPA 54:9.6.5.1(A)]

Exceptions:

(1) Shutoff valves serving decorative appliances in a fireplace shall not be located within the fireplace firebox except where the valve is listed for such use. [NFPA 54: 9.6.5.1(B)]

(2) Shutoff valves shall be permitted to be accessibly located inside wall heaters and wall furnaces listed for recessed

installation where necessary maintenance is performed without removal of the shutoff valve.

1312.7 Quick-Disconnect Devices. Quick-disconnect devices used to connect appliances to the building piping shall be listed in accordance with ANSI Z21.41/CSA 6.9.

Where installed indoors, an approved manual shutoff valve with a nondisplaceable valve member shall be installed upstream of the quick-disconnect device. [NFPA 54:9.6.6 – 9.6.6.2]

1312.8 Gas Convenience Outlets. Appliances shall be permitted to be connected to the building piping by means of a listed gas convenience outlet, in conjunction with a listed appliance connector, installed in accordance with the manufacturer’s installation instructions.

Gas convenience outlets shall be listed in accordance

with CSA/ANSI Z21.90/CSA 6.24 and installed in accor dance with the manufacturer’s installation instructions.

[NFPA 54:9.6.7]

1312.9 Sediment Trap. Where a sediment trap is not incorporated as a part of the appliance, a sediment trap shall be installed downstream of the appliance shutoff valve as close to the inlet of the appliance as practical at the time of appliance installation. The sediment trap shall be either a tee fitting with a capped nipple in the bottom outlet, as illustrated in Figure 1312.9, or another device recognized as an effective sediment trap. Illuminating appliances, gas ranges, clothes dryers, decorative appliances for installation in vented fireplaces, gas fireplaces, and outdoor cooking appliances shall not be required to be so equipped. [NFPA 54:9.6.8]

For SI units: 1 inch = 25.4 mm

FIGURE 1312.9

METHOD OF INSTALLING A TEE FITTING SEDIMENT TRAP
CMC § 1310.4 High relevance — show source text
1310.4 Concealed Piping in Buildings . . . 285

1310.5 Piping in Vertical Chases . . . . . . . 286

1310.6 Maximum Operating Pressure in Buildings . . . . . . . . . . . . . . . . . . 286

1310.7 Appliance Overpressure Protection . . . . . . . . . . . . . . . . . . . 286

1310.8 Gas Pipe Turns. . . . . . . . . . . . . . . 286

1310.9 Drips and Sediment Traps . . . . . . 287

1310.10 Outlets . . . . . . . . . . . . . . . . . . . . . 287

1310.11 Manual Gas Shutoff Valves . . . . . 287

1310.12 Prohibited Devices . . . . . . . . . . . . 288

1310.13 Systems Containing Gas-Air Mixtures Outside the Flammable

Range . . . . . . . . . . . . . . . . . . . . . . 288

1310.14 Systems Containing Flammable Gas-Air Mixtures. . . . . . . . . . . . . . 288

1311.0 Electrical Bonding and Grounding. . . . . . . . . . . . . . . . . . . 289

1311.1 Pipe and Tubing other than CSST . . . . . . . . . . . . . . . . . . . . . . 289

1311.2 Bonding of CSST Gas Piping . . . . 289

1311.3 Arc-Resistant Jacketed CSST . . . 289

1311.4 Prohibited Use . . . . . . . . . . . . . . . 289

1311.5 Lightning Protection System. . . . . 289

1311.6 Electrical Circuits . . . . . . . . . . . . . 289

1311.7 Electrical Connections . . . . . . . . . 289

1312.0 Appliance and Equipment Connections to Building Piping. . . 289

1312.1 Connecting Appliances and Equipment . . . . . . . . . . . . . . . . . . 289

2025 CALIFORNIA MECHANICAL CODE

1312.2 Suspended Low-Intensity Infrared Tube Heaters . . . . . . . . . 290

1312.3 Use of Nonmetallic Gas Hose

Connectors . . . . . . . . . . . . . . . . . . 290

1312.4 Injection (Bunsen) Burners . . . . . . 290

1312.5 Connection of Portable and

Mobile Industrial Appliances. . . . . 290

1312.6 Appliance Shutoff Valves and Connections. . . . . . . . . . . . . . 291

1312.7 Quick-Disconnect Devices . . . . . . 291

1312.8 Gas Convenience Outlets. . . . . . . 291

1312.9 Sediment Trap . . . . . . . . . . . . . . . 291

1312.10 Installation of Piping . . . . . . . . . . . 291

1312.11 Liquefied Petroleum Gas Facilities and Piping . . . . . . . . . . . 291
CMC § 1311.4 High relevance — show source text
1311.4 Prohibited Use . . . . . . . . . . . . . . . 289

1311.5 Lightning Protection System. . . . . 289

1311.6 Electrical Circuits . . . . . . . . . . . . . 289

1311.7 Electrical Connections . . . . . . . . . 289

1312.0 Appliance and Equipment Connections to Building Piping. . . 289

1312.1 Connecting Appliances and Equipment . . . . . . . . . . . . . . . . . . 289

2025 CALIFORNIA MECHANICAL CODE

1312.2 Suspended Low-Intensity Infrared Tube Heaters . . . . . . . . . 290

1312.3 Use of Nonmetallic Gas Hose

Connectors . . . . . . . . . . . . . . . . . . 290

1312.4 Injection (Bunsen) Burners . . . . . . 290

1312.5 Connection of Portable and

Mobile Industrial Appliances. . . . . 290

1312.6 Appliance Shutoff Valves and Connections. . . . . . . . . . . . . . 291

1312.7 Quick-Disconnect Devices . . . . . . 291

1312.8 Gas Convenience Outlets. . . . . . . 291

1312.9 Sediment Trap . . . . . . . . . . . . . . . 291

1312.10 Installation of Piping . . . . . . . . . . . 291

1312.11 Liquefied Petroleum Gas Facilities and Piping . . . . . . . . . . . 291

1313.0 Pressure Testing, Inspection, and Purging. . . . . . . . . . . . . . . . . . 291

1313.1 Piping Installations . . . . . . . . . . . . 291

1313.2 Test Preparation . . . . . . . . . . . . . . 292

1313.3 Test Pressure . . . . . . . . . . . . . . . . 292

1313.4 Detection of Leaks and Defects . . 292

1313.5 Piping System Leak Test . . . . . . . 292

1313.6 Purging Requirements . . . . . . . . . 292

Table 1313.6.1 Size and Length of Piping. . . . . . . 293

1314.0 Required Gas Supply . . . . . . . . . . 293

1314.1 General. . . . . . . . . . . . . . . . . . . . . 293

1314.2 Volume . . . . . . . . . . . . . . . . . . . . . 293

1314.3 Gas Appliances . . . . . . . . . . . . . . 294

1314.4 Size of Piping Outlets . . . . . . . . . . 294

1315.0 Required Gas Piping Size . . . . . . 294

1315.1 Pipe Sizing Methods. . . . . . . . . . . 294

1315.2 Sizing of Gas Piping Systems . . . 294

1315.3 Sizing Equations. . . . . . . . . . . . . . 294

Table 1315.3 Cr and Y for Natural Gas and
CMC § 1210.3.5.1 High relevance — show source text
Table 1210.3.5.1 Support of Piping . . . . . . . . . . . . .225

1210.4 Concealed Piping in Buildings . . .225

1210.5 Piping in Vertical Chases . . . . . . .226

1210.6 Gas Pipe Turns . . . . . . . . . . . . . .226

1210.7 Drips and Sediment Traps . . . . . .227

1210.8 Outlets . . . . . . . . . . . . . . . . . . . . .227

1210.9 Manual Gas Shutoff Valves . . . . .227

1210.10 Prohibited Devices . . . . . . . . . . . .227

1210.11 Systems Containing Gas-Air Mixtures Outside the

Flammable Range . . . . . . . . . . . .227

1210.12 Systems Containing Flammable Gas-Air Mixtures . . . . . . . . . . . . . .227

1211.0 Electrical Bonding and Grounding . . . . . . . . . . . . . . . . . . .229

1211.1 Pipe and Tubing Other than CSST . . . . . . . . . . . . . . . . . . . . . .229

1211.2 Bonding of CSST Gas Piping . . . .229

1211.3 Arc-Resistant Jacketed CSST . . .229

1211.4 Prohibited Use . . . . . . . . . . . . . . .229

1211.5 Lightning Protection System . . . . .229

1211.6 Electrical Circuits . . . . . . . . . . . . .229

1211.7 Electrical Connections . . . . . . . . .229

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TABLE OF CONTENTS

1211.8 Earthquake-Actuated Gas Shutoff Valves . . . . . . . . . . . . . . . .229

1212.0 Appliance and Equipment Connections to Building Piping . . .229

1212.1 Connecting Appliances and Equipment . . . . . . . . . . . . . . . . . .229

1212.2 Suspended Low-Intensity Infrared Tube Heaters . . . . . . . . .230

1212.3 Use of Nonmetallic Gas

Hose Connectors . . . . . . . . . . . . .230

1212.4 Injection (Bunsen) Burners . . . . . .230

1212.5 Connection of Portable

and Mobile Industrial

Gas Appliances . . . . . . . . . . . . . .230

1212.6 Appliance Shutoff Valves and Connections . . . . . . . . . . . . . .230

1212.7 Quick-Disconnect Devices . . . . . .230

1212.8 Gas Convenience Outlets . . . . . .231

1212.9 Sediment Trap . . . . . . . . . . . . . . .231

1212.10 Installation of Piping . . . . . . . . . . .231

1212.11 Liquefied Petroleum Gas Facilities and Piping . . . . . . . . . . .231
CMC § 1310.9 Medium relevance — show source text
1310.9 Drips and Sediment Traps. For other than dry gas conditions, a drip shall be provided at any point in the line of pipe where condensate could collect. Where required by the Authority Having Jurisdiction or the serving gas supplier, a drip shall also be provided at the outlet of the meter. This drip shall be installed so as to constitute a trap wherein an accumulation of condensate shuts off the flow of gas before it runs back into the meter. [NFPA 54:7.6.1]

1310.9.1 Location of Drips. All drips shall be installed only in such locations that they are readily accessible to permit cleaning or emptying. A drip shall not be located where the condensate is likely to freeze.

[NFPA 54:7.6.2]

1310.9.2 Sediment Traps. The installation of sediment traps shall be in accordance with Section 1312.9.

[NFPA 54:7.6.3]

1310.10 Outlets. Outlets shall be located and installed in accordance with the following requirements:

(1) The outlet fittings or piping shall be securely fastened in place.

(2) Outlets shall not be located behind doors.

(3) Outlets shall be located far enough from floors, walls, patios, slabs, and ceilings to permit the use of wrenches without straining, bending, or damaging the piping.

(4) The unthreaded portion of gas piping outlets shall extend not less than 1 inch (25.4 mm) through finished ceilings or indoor or outdoor walls.

(5) The unthreaded portion of gas piping outlets shall extend not less than 2 inches (51 mm) above the surface of floors or outdoor patios or slabs.

(6) The provisions of Section 1310.10(4) and Section 1310.10(5) shall not apply to listed quick-disconnect devices of the flush-mounted type or listed gas convenience outlets. Such devices shall be installed in accor dance with the manufacturer’s installation instructions.

[NFPA 54:7.7.1.1 – 7.7.1.6] 1310.10.1 Cap Outlets. Each outlet, including a valve, shall be closed gastight with a threaded plug or cap immediately after installation and shall be left closed until the appliance or equipment is connected thereto. When an appliance or equipment is disconnected from an outlet and the outlet is not to be used again immediately, it shall be capped or plugged gastight.

Exceptions:

(1) Laboratory appliances installed in accordance with Section 1312.3.1 shall be permitted.

(2) The use of a listed quick-disconnect device with integral shutoff or listed gas convenience outlet shall be permitted. [NFPA 54:7.7.2.1] 1310.10.1.1 Appliance Shutoff Valves. Appliance shutoff valves installed in fireplaces shall be removed and the piping capped gastight where the fireplace is used for solid fuel burning. [NFPA 54:7.7.2.2] 1310.11 Manual Gas Shutoff Valves. An accessible gas shutoff valve shall be provided upstream of each gas pressure regulator. Where two gas pressure regulators are installed in series in a single gas line, a manual valve shall not be required at the second regulator.

CMC § 03-25 Medium relevance — show source text

If several insulated aluminum conductors are to be connected to one insulated copper conductor, each aluminum conductor must first be spliced to a short length of copper conductor so that the multiple connection can be made with all copper conductors. This multiple connection may be a tee tap (or several tee taps) as shown in Document 051034.
Special care must be used to prevent moisture from entering through the copper strands when connecting a bare stranded copper conductor to an insulated aluminum conductor (e.g., copper-to-aluminum neutral connection). See Figure 1 below for these connections.

Insulated PVC Tape (as required) Conductor

Figure 1 Connection Between Bare and Insulated Conductor

Rev. #07: 03-25-22 015251 Page 7 of 39

UG-1: Connectors Greenbook Connectors for Insulated Cables Underground Distribution Systems

Straight Connectors Compression-Type (predrilled) Copper-to-Aluminum

A

L	Col2	Col3
		O
L AA BB	L AA BB	L AA BB

(copper or aluminum)

Crimps Made

Conductor A Conductor B

Figure 2 Figure 3 Overall Dimensions View After Connector Installation (for Figure 2)

Table 3 Compression-Type Connectors − Predrilled

Conductor Size − AWG or kcmil	Col2	Connector Dimensions (inches)	Col4	Col5	Col6	Manufacturer and Catalog Numbers	Col8	Col9	6-Ton Tool Die # 5 12-Ton Tool Die # 15-Ton ToolDie #	Connector Code
A 1 (Cu or Al)	B (Al)	AA	BB	L 2	OD	Burndy	Richards	Homac	Homac	Homac
4	2	1.03	1.03	2.75	0.65	SeeDocument 028852	SeeDocument 028852	SeeDocument 028852	W-BG U-BG U-BG4	3055583
2	2	2	2	2	2	2	2	2	2	3055593
2	1	1	1	1	1	YR1CA2CCAG1	ALCR 8-7	SAC1R2	SAC1R2	305569
2	1/0	1/0	1/0	1/0	1/0	SeeDocument 028852	SeeDocument 028852	SeeDocument 028852	SeeDocument 028852	3055623
2	1/0	1/0	1/0	1/0	1/0	SeeDocument 028852
2	2/0	1.56	1.56	4.00	0.

CMC § 1310.8.1 Medium relevance — show source text
1310.8.1 Metallic Pipe. Metallic pipe bends shall comply with the following:

(1) Bends shall be made only with bending tools and procedures intended for that purpose.

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FUEL GAS PIPING

(2) All bends shall be smooth and free from buckling, cracks, or other evidence of mechanical damage.

(3) The longitudinal weld of the pipe shall be near the neutral axis of the bend.

(4) Pipe shall not be bent through an arc of more than 90 degrees.

(5) The inside radius of a bend shall be not less than 6 times the outside diameter of the pipe. [NFPA 54:7.5.1]

1310.8.2 Plastic Pipe. Plastic pipe bends shall comply with the following:

(1) The pipe shall not be damaged, and the internal diameter of the pipe shall not be effectively reduced.

(2) Joints shall not be located in pipe bends.

(3) The radius of the inner curve of such bends shall not be less than 25 times the inside diameter of the pipe.

(4) Where the piping manufacturer specifies the use of special bending tools or procedures, such tools or procedures shall be used. [NFPA 54:7.5.2]

1310.8.3 Elbows. Factory-made welding elbows or transverse segments cut therefrom shall have an arc length measured along the crotch of at least 1 inch (25 mm) for pipe sizes 2 inches (50 mm) and larger. [NFPA 54:7.5.3]

1310.9 Drips and Sediment Traps. For other than dry gas conditions, a drip shall be provided at any point in the line of pipe where condensate could collect. Where required by the Authority Having Jurisdiction or the serving gas supplier, a drip shall also be provided at the outlet of the meter. This drip shall be installed so as to constitute a trap wherein an accumulation of condensate shuts off the flow of gas before it runs back into the meter. [NFPA 54:7.6.1]

1310.9.1 Location of Drips. All drips shall be installed only in such locations that they are readily accessible to permit cleaning or emptying. A drip shall not be located where the condensate is likely to freeze.

[NFPA 54:7.6.2]

1310.9.2 Sediment Traps. The installation of sediment traps shall be in accordance with Section 1312.9.

[NFPA 54:7.6.3]

1310.10 Outlets. Outlets shall be located and installed in accordance with the following requirements:

(1) The outlet fittings or piping shall be securely fastened in place.

(2) Outlets shall not be located behind doors.

(3) Outlets shall be located far enough from floors, walls, patios, slabs, and ceilings to permit the use of wrenches without straining, bending, or damaging the piping.

(4) The unthreaded portion of gas piping outlets shall extend not less than 1 inch (25.4 mm) through finished ceilings or indoor or outdoor walls.
CMC § 802.10.5 Medium relevance — show source text
802.10.5 Joints. Joints between sections of connector piping and connections to flue collars or draft hood outlets shall be fastened in accordance with one of the following methods:

(1) Mechanically fastened by means of not less than three sheet-metal screws equally spaced around the joint.

(2) Vent connectors of listed vent material assembled and connected to flue collars or draft hood outlets in

accordance with the manufacturer’s instructions.

(3) Other approved means. {NFPA 54:12.11.6}

802.10.6 Connector Junctions. Where vent connectors are joined together, the connection shall be made with a manufactured tee or wye fitting. [NFPA 54:12.11.7]

802.10.7 Slope. A vent connector shall be installed without any dips or sags and shall slope upward toward the vent or chimney at least [1] ⁄ 4 inch per foot (20.8 mm/m).

Exception: Vent connectors attached to a mechanical draft system installed in accordance with appliance and the draft system manufacturers’ instructions. [NFPA 54:12.11.8]

802.10.8 Length of Vent Connector. The length of vent connectors shall comply with Section 802.10.8.1 or Section 802.10.8.2.

802.10.8.1 Single Wall Connector. The maximum horizontal length of a single-wall connector shall be 75 percent of the height of the chimney or vent, except for engineered systems. [NFPA 54:12.11.9.1]

802.10.8.2 Type B Double Wall Connector. The maximum horizontal length of a Type B double-wall connector shall be 100 percent of the height of the chimney or vent, except for engineered systems. The maximum length of an individual connector for a chimney or vent system serving multiple

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164 2025 CALIFORNIA MECHANICAL CODE

), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.

CHIMNEYS AND VENTS

ances requiring chimney draft for operation; single-firebox boilers equipped with conversion burners with inputs greater than 400 000 Btu/h (117 kW); appliances equipped with blast, power, or pressure burners that are not listed for use with draft hoods; and appliances designed for forced venting. [NFPA 54:12.13.1]

802.12.1 Installation. A draft hood supplied with or forming a part of a listed vented appliance shall be installed without alteration, exactly as furnished and specified by the appliance manufacturer. [NFPA 54:12.13.2]

If a draft hood is not supplied by the appliance manufacturer where one is required, a draft hood shall be installed, be of a listed or approved type, and, in the absence of other instructions, be of the same size as the appliance flue collar. Where a draft hood is required with a conversion burner, it shall be of a listed or approved type. [NFPA 54:12.13.2.1]

802.12.2 Draft Control Devices. Where a draft con trol device is part of the appliance or is supplied by the appliance manufacturer, it shall be installed in accordance with the manufacturer’s instructions. In the

Frequently asked questions

Do I have to install a tee trap for every gas appliance?

If the appliance does not include a built‑in sediment trap, yes—you must install a sediment trap downstream of the appliance shutoff valve and as close to the appliance inlet as practical (exceptions listed in § 1312.9).

Can I use something other than a tee fitting with a capped nipple?

Yes—another device recognized as an effective sediment trap is permitted if approved or listed as effective. § 1312.9.

Are clothes dryers and ranges required to have sediment traps?

No. Clothes dryers, gas ranges, certain illuminating or decorative appliances, gas fireplaces, and outdoor cooking appliances are exempt from the sediment‑trap requirement in § 1312.9.

How close to the appliance inlet is “practical”?

The code uses the phrase “as close to the inlet of the appliance as practical” rather than a set distance; place the trap as near the inlet as feasible so it effectively intercepts sediment and remains serviceable. § 1312.9.

Who decides LP‑Gas-specific details like tank placement and clearances?

The CMC requires LP‑Gas facilities and piping to comply with NFPA 58; consult NFPA 58 for detailed LP‑Gas requirements referenced by § 1312.11.

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