CMC · California Mechanical Code
Installation Practices, Inspections, Permits and Operation
This hub orients users to the CMC rules for proper installation, required permits and inspections, and procedures to place mechanical systems into safe operation.
Last reviewed: July 6, 2026
Overview
This section of the California Mechanical Code (CMC) organizes the rules you need to install mechanical systems correctly, obtain required permits, pass mandated inspections, and place equipment into safe operation. It ties the administration and permitting framework in Chapter 1 (permits, fees and plan review) to the installation, workmanship, testing and inspection provisions that govern specific systems such as process piping and fuel equipment. See §1.8.4.1 for the written-permit requirement and related plan‑review rules , and Chapter 14 for process‑piping permit and inspection requirements (for example §1402.1 and the inspection provisions in §1405) .
Why this matters: permits, inspections and operation procedures are the compliance pathway that protects public safety, verifies pressure‑ and combustion‑safety tests, and documents Authority Having Jurisdiction (AHJ) approval before systems enter service. The CMC also provides workmanship and testing rules (for example §1404.1 and the required rough and final piping inspections and tests in §1405.2.1–§1405.2.2) that inspectors use to evaluate installations and to approve final operation. Specialized commissioning and start‑up procedures (for gas and fuel equipment) are organized in the appendices (see Appendix B and Appendix C) to guide safe placement of equipment into service .
In this section
- What are inspection, operating permit, and inspection-frequency requirements?
- What installation access and maintenance clearances are required for boilers?
- What operating instructions and control diagrams must the installer provide?
- When do NFPA 85 requirements apply to boilers, stokers and steam generators?
Code references
Grounded in the retrieved California Mechanical Code — click a citation to read the verbatim passage:
CMC § 1401.0 High relevance — show source text
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CHAPTER 14
PROCESS PIPING
1401.0 General.
1401.1 Applicability. Except as otherwise addressed in this code, this chapter shall govern the installation of process piping in or in conjunction with a building or structure located upon the premises.
1402.0 Permit.
1402.1 General. It shall be unlawful to install, alter, or repair or cause to be installed, altered, or repaired process material piping without first obtaining a permit.
Permits for process piping shall show the total number of outlets to be provided for on each system and such other information as required by the Authority Having Jurisdiction.
Fees for process piping permits are included in Table 104.5.
1403.0 Plans Required.
1403.1 General. Plans, engineering calculations, diagrams, and other data shall be submitted in one or more sets with each application for a permit. The Authority Having Jurisdiction shall be permitted to require plans, computations, and specifications to be prepared and designed by a registered design professional.
Where plans or other data are submitted for review, a plan review fee shall be paid, as provided in Section 104.3.2.
1404.0 Workmanship.
1404.1 General. Process piping shall not be strained or bent, nor shall tanks, vessels, vats, appliances, or cabinets be supported by or develop strain or stress on the piping.
1405.0 Inspections.
1405.1 General. Upon completion of the installation, alteration, or repair of process piping, and prior to the use thereof, the Authority Having Jurisdiction shall be notified that such piping is ready for inspection.
Excavations required for the installation of underground piping shall be kept open until such time as the piping has been inspected and approved. Where such piping is covered or concealed before such approval, it shall be exposed upon the direction of the Authority Having Jurisdiction.
1405.2 Required Inspections. The Authority Having Jurisdiction shall make the following inspections and shall either approve that portion of the work as completed or shall notify the permit holder wherein the same fails to be in accordance with this code.
1405.2.1 Rough Piping Inspection. This inspection shall be made after process piping authorized by the permit has been installed and before piping has been cov
ered or concealed. This inspection shall include a determination that the piping size, material, and installation are in accordance with the requirements of this code.
1405.2.2 Final Piping Inspection. This inspection shall be made after piping authorized by the permit has been installed and after portions thereof that are to be covered or concealed are so concealed. This inspection shall include a pressure test, at which time the piping shall stand a pressure of not less than one-and-one-half times the maximum designed operating pressure where hydraulic testing is conducted or 110 percent where testing is conducted pneumatically. Test pressures shall be held for a length of time satisfactory to the Authority Having Jurisdiction, but in no case for less than 30 minutes with no perceptible drop in pressure. HPM drain, waste, and vent piping shall be tested in accordance with the plumbing code. Tests shall be made in the presence of the Authority Having Jurisdiction. Necessary apparatus for conducting tests shall be furnished by the permit holder.
CMC § 2.3 High relevance — show source text
**_ Refer to the Special Occupancy Parks Act, California Health and Safety Code, Division 13, Part 2.3, commencing with Section 18860 and California Code of Regulations, Title 25, Division 1, Chapter 2.2, commencing with Section 2000 for special occupancy park administra- tive and enforcement authority, permits, fees, viola- tions, inspections, and penalties both within and outside of special occupancy parks. Exception: Special occupancy parks where the Department of Housing and Community Develop- ment is the enforcing agency. 1.8.3.2.4 Employee Housing Act. Refer to the Employee Housing Act, California Health and Safety Code, Division 13, Part 1, commencing with Section 17000 and California Code of Regulations, Title 25, Division 1, Chapter 1, Subchapter 3, commencing with Section 600 for employee housing administrative and enforcement authority, permits, fees, violations, inspections, and penalties. 1.8.3.2.5 Factory-Built Housing Law. Refer to the Factory-Built Housing Law, California Health and Safety Code, Division 13, Part 6, commencing with Section 19960 and California Code of Regulations, Title 25, Division 1, Chapter 3, Subchapter 1, commencing with Section 3000 for factory-built housing administrative and enforcement authority, permits, fees, violations, inspections, and penalties. 1.8.4 Permits, Fees, Applications, and Inspections. 1.8.4.1 Permits. A written construction permit shall be obtained from the enforcing agency prior to the erection, construction, reconstruction, installation, relocation, or alteration of any mechanical system. Exceptions: (1) Work exempt from permits as specified in Chapter 1, Scope and Administration, Division II, Section 104.2 Items (1) through (5) of this code. (2) Changes, alterations, or repairs of a minor nature not affecting structural features, egress, sanitation, safety, or accessibility as determined by the enforcing agency.
(3) Retroactive permits issued in accordance with Health and Safety Code Section 17958.12.
Exemptions from permit requirements shall not be deemed to grant authorization for any work to be done in any manner in violation of other provisions of law or this code. 1.8.4.2 Fees. Subject to other provisions of law, the governing body of any city, county, or city and county may prescribe fees to defray the cost of enforcement of rules and regulations promulgated by the Department of Housing and Community Development. The amount of the fees shall not exceed the amount reasonably neces- sary to administer or process permits, certificates, forms, or other documents, or to defray the costs of enforcement. For additional information, see State Housing Law, Health and Safety Code, Division 13, Part 1.5, Section 17951 and California Code of Regulations, Title 25, Divi- sion 1, Chapter 1, Subchapter 1, Article 3, commencing with Section 6.
_**1.8.4.3 Plan Review and Time Limitations.
CEC § 384 High relevance — show source text
384 2025 CALIFORNIA MECHANICAL CODE
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APPENDICES
The appendices are intended to supplement the provisions of the installation requirements of this code. The definitions in Chapter 2 are also applicable to the appendices.
TABLE OF CONTENTS
»
»
Appendix A Page
Residential Plans Examiner Review Form for HVAC System Design..............................................................387
Appendix B
Procedures to be Followed to Place Gas Equipment in Operation..................................................................391
Appendix C
Installation and Testing of Oil (Liquid) Fuel-Fired Equipment ..........................................................................395
Appendix D
Fuel Supply: Manufactured/Mobile Home Parks and Recreational Vehicle Parks ..........................................403
Appendix E
Sustainable Practices ......................................................................................................................................411
Appendix F
Sizing of Venting Systems and Outdoor Combustion and Ventilation Opening Design ..................................533
Appendix G
Example Calculation of Outdoor Air Rate........................................................................................................545
Appendix H
Professional Qualifications ..............................................................................................................................549
Appendix I
Indoor Horticultural Facilities ..........................................................................................................................553
Appendix J
Clean Air Delivery............................................................................................................................................559
2025 CALIFORNIA MECHANICAL CODE 385
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CALIFORNIA MECHANICAL CODE – MATRIX ADOPTION TABLE
APPENDIX A – RESIDENTIAL PLAN EXAMINER REVIEW FORM FOR HVAC SYSTEM DESIGN
(Matrix Adoption Tables are non-regulatory, intended only as an aid to the code user. See Chapter 1 for state agency authority and building applications.)
Adopting Agency BSC BSC-
CGSFM HCD Col6 Col7 DSA Col9 Col10 OSHPD Col12 Col13 Col14 Col15 Col16 Col17 BSCC DPH AGR DWR CEC CA SL SLC Adopting Agency BSC BSC-
CGSFM 1 2 1-AC AC ** SS** ** SS/CC** 1 1R 2 3 4 5 6 6 6 6 6 6 6 6 6 Adopt Entire Chapter Adopt Entire Chapter as
amended (amended sections
listed below)Adopt only those sections
that are listed belowChapter/Section CMC § 10005-4026. High relevance — show source text
IES Illuminating Engineering Society, 120 Wall St. Fl 17, New York, NY 10005-4026.
IEST Institute of Environmental Sciences and Technology, 1827 Walden Office Square, Suite 400, Schaumburg, IL 60173.
IGSHPA International Ground Source Heat Pump Association, 1723 W. Tyler Ave. Stillwater, OK 74078.
IIAR International Institute of Ammonia Refrigeration, 1001 N. Fairfax Street, Suite 503, Alexandria, VA 22314.
ISO International Organization for Standardization, 1 ch. de la Voie-Creuse, Casa Postale 56, CH-1211 Geneva 20, Switzerland.
MSS Manufacturers Standardization Society of the Valve and Fittings Industry, 127 Park Street NE, Vienna, VA 22180.
NAIMA North American Insulation Manufacturers Association, Inc., 11 Canal Center Plaza #103, Alexandria, VA 22314.
NEBB National Environmental Balancing Bureau, 8575 Grovemont Circle, Gaithersburg, MD 20877.
NFPA National Fire Protection Association, 1 Batterymarch Park, Quincy, MA 02169-7471.
NGWA National Ground Water Association, 601 Dempsey Road, Westerville, Ohio 43081-8978.
NSF NSF International, 789 N. Dixboro Road, Ann Arbor, MI 48105.
SAE Society of Automotive Engineers, 400 Commonwealth Drive, Warrendale, PA 15096.
SMACNA Sheet Metal and Air Conditioning Contractors National Association, 4201 Lafayette Center Drive, Chantilly, VA 20151-1219.
UL Underwriters Laboratories, Inc., 333 Pfingsten Road, Northbrook, IL 60062.
384 2025 CALIFORNIA MECHANICAL CODE
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APPENDICES
The appendices are intended to supplement the provisions of the installation requirements of this code. The definitions in Chapter 2 are also applicable to the appendices.
TABLE OF CONTENTS
»
»
Appendix A Page
Residential Plans Examiner Review Form for HVAC System Design..............................................................387
Appendix B
Procedures to be Followed to Place Gas Equipment in Operation..................................................................391
Appendix C
Installation and Testing of Oil (Liquid) Fuel-Fired Equipment ..........................................................................395
Appendix D
Fuel Supply: Manufactured/Mobile Home Parks and Recreational Vehicle Parks ..........................................403
Appendix E
Sustainable Practices ......................................................................................................................................411
Appendix F
Sizing of Venting Systems and Outdoor Combustion and Ventilation Opening Design ..................................533
Appendix G
Example Calculation of Outdoor Air Rate........................................................................................................545
Appendix H
Professional Qualifications ..............................................................................................................................549
Appendix I
Indoor Horticultural Facilities ..........................................................................................................................553
Appendix J
Clean Air Delivery............................................................................................................................................559
2025 CALIFORNIA MECHANICAL CODE 385
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386 2025 CALIFORNIA MECHANICAL CODE
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CMC § 1.8.3.2.1 High relevance — show source text
1.8.3.2.1 State Housing Law. Refer to the State Housing Law, California Health and Safety Code, Division 13, Part 1.5, commencing with Section 17910, and California Code of Regulations, Title 25,
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DIVISION I CALIFORNIA ADMINISTRATION
Division 1, Chapter 1, Subchapter 1, commencing with Section 1, for the erection, construction, recon- struction, movement, enlargement, conversion, alter- ation, repair, removal, demolition, or arrangement of apartments, condominiums, hotels, motels, lodging houses, and dwellings, including accessory buildings, facilities, and uses thereto.
1.8.3.2.2 Mobilehome Parks Act. Refer to the Mobilehome Parks Act, California Health and Safety Code, Division 13, Part 2.1, commencing with Section 18200 and California Code of Regula- tions, Title 25, Division 1, Chapter 2, commencing with Section 1000 for mobilehome park administra- tive and enforcement authority, permits, plans, fees, violations, inspections, and penalties both within and outside mobilehome parks. Exception: Mobilehome parks where the Depart- ment of Housing and Community Development is the enforcing agency. 1.8.3.2.3 Special Occupancy Parks Act. Refer to the Special Occupancy Parks Act, California Health and Safety Code, Division 13, Part 2.3, commencing with Section 18860 and California Code of Regulations, Title 25, Division 1, Chapter 2.2, commencing with Section 2000 for special occupancy park administra- tive and enforcement authority, permits, fees, viola- tions, inspections, and penalties both within and outside of special occupancy parks. Exception: Special occupancy parks where the Department of Housing and Community Develop- ment is the enforcing agency. 1.8.3.2.4 Employee Housing Act. Refer to the Employee Housing Act, California Health and Safety Code, Division 13, Part 1, commencing with Section 17000 and California Code of Regulations, Title 25, Division 1, Chapter 1, Subchapter 3, commencing with Section 600 for employee housing administrative and enforcement authority, permits, fees, violations, inspections, and penalties. 1.8.3.2.5 Factory-Built Housing Law. Refer to the Factory-Built Housing Law, California Health and Safety Code, Division 13, Part 6, commencing with Section 19960 and California Code of Regulations, Title 25, Division 1, Chapter 3, Subchapter 1, commencing with Section 3000 for factory-built housing administrative and enforcement authority, permits, fees, violations, inspections, and penalties. 1.8.4 Permits, Fees, Applications, and Inspections. _**1.8.4.1 Permits.
California Mechanical Code High relevance — show source text
2
5
10
15|36
38
51
NA
NA|93
69
63
NA
NA|57
47
44
39
NA|56
57
75
95
NA|190
136
128
116
NA|111
93
86
79
72|80
80
102
128
158|325
225
216
201
186|186
149
140
131
124|116
115
144
182
220|499
337
326
308
290|283
224
217
203
192|153
148
182
228
272|713
473
459
438
418|388
314
298
284
269| |20|0
2
5
10
15
20|35
37
50
NA
NA
NA|96
74
68
NA
NA
NA|60
50
47
41
NA
NA|54
56
73
93
NA
NA|200
148
140
129
NA
NA|118
99
94
86
80
NA|78
78
100
125
155
186|346
248
239
223
208
192|201
165
158
146
136
126|114
113
141
177
216
254|537
375
363
344
325
306|306
248
239
224
210
196|149
144
178
222
264
309|772
528
514
491
469
448|428
344
334
316
301
285| |30|0
2
5CMC § 1-2 High relevance — show source text
2022 – 2023 1-2
Section 1, General
1.1. (continued)
These regulations and orders include, but are not limited to, the following documents:
“ ” General Order (G.O.) 95, Rules for Overhead Electric Line Construction
G.O. 112-F, “Rules Governing Design, Construction, Testing, Operation, and Maintenance of Gas Gathering, Transmission, and Distribution Piping Systems”
G.O. 128, “Rules for Construction of Underground Electric Supply and Communication Systems”
Code of Federal Regulations ( CFR ), Title 49, “Transportation,” Part 192, “Transportation of Natural and Other Gas by Pipeline: Minimum Federal Safety Standards”
Finally, applicants must comply with all other federal, state, and local regulations. These regulations may include a Federal Aviation Administration (FAA) review for structures that impinge on navigable airspace. In such cases, the FAA requires filing notice of proposed construction a minimum of 45 days before starting the proposed construction. The FAA may issue a determination of hazard to air navigation and recommend actions to mitigate or eliminate that hazard. For additional information, please contact your PG&E project coordinator.
1.2. Permits and Inspections
Builders who are constructing new buildings or remodeling existing buildings must conform to the following guidance documents.
A. The current provisions of city and county ordinances.
B. Rules on file with, or issued by, the CPUC.
C. Applicable rules and laws of the state of California, including, but not limited to, the following three codes.
- Plumbing codes - Mechanical codes - Electric codesLocal and state ordinances require applicants to obtain the appropriate permits and final inspections before PG&E establishes services to any building or structure.
In areas where local ordinances governing gas or electrical installations do not exist, or where inspections provided by local jurisdictions for such installations are not available, the applicant must obtain written confirmation from a qualified person that the facilities meet the requirements specified in this manual.
PG&E will not establish gas or electric service until the gas piping or electric service facilities are installed satisfactorily.
N OTE : Gas meter release forms obtained from a permitting agency must include the specific, requested pressure (e.g., 7-inches w.c., 2 psig, 5 psig).
1-3 2022 – 2023
Section 1, General
1.2. (continued)
PG&E’s inspection process includes service requirements that are not governed by local or state codes. Parts of the applicant’s installation may require approval by state, local, and PG&E inspectors .
CMC § 306.0 High relevance — show source text
306.0 Industrial Wastes.
306.1 Detrimental Wastes. Wastes detrimental to the public sewer system or detrimental to the functioning of the sewage treatment plant shall be treated and disposed of as found necessary and directed by the Authority Having Jurisdiction. 306.2 Safe Discharge. Sewage or other waste from a plumbing system that is capable of being deleterious to surface or subsurface waters shall not be discharged into the ground or a waterway unless it has first been rendered safe by some acceptable form of treatment in accordance with the Authority Having Jurisdiction.
307.0 Location.
307.1 System. Except as otherwise provided in this code, no plumbing system, drainage system, building sewer, private sewage disposal system, or parts thereof shall be located in a lot other than the lot that is the site of the building, structure, or premises served by such facilities.
307.2 Ownership. No subdivision, sale, or transfer of ownership of existing property shall be made in such manner that the area, clearance, and access requirements of this code are decreased.
308.0 Prohibited Locations.
308.1 General. Piping, fixtures, appliances, or equipment shall not be so located as to interfere with the normal use thereof or with the normal operation and use of windows, doors, or other required facilities.
309.0 Workmanship.
309.1 Engineering Practices. Design, construction, and workmanship shall be in accordance with accepted engineering practices and shall be of such character as to secure the results sought to be obtained by this code. 309.2 Concealing Imperfections. It is unlawful to conceal cracks, holes, or other imperfections in materials by welding, brazing, or soldering or by using therein or thereon paint, wax, tar, solvent cement, or other leak-sealing or repair agent.
309.3 Burred Ends. Burred ends of pipe and tubing shall be reamed to the full bore of the pipe or tube, and chips shall be removed.
309.4 Installation Practices. Plumbing systems shall be installed in a workmanlike manner which is in accordance with this code, applicable standards, and the manufacturer’s installation instructions. All materials shall be installed so as not to adversely affect the systems and equipment or the structure of the building, and in compliance with all laws and other provisions of this code. All plumbing systems shall be in accordance with construction documents approved by the Authority Having Jurisdiction. 309.5 Sound Transmission. Plumbing piping systems shall be designed and installed in conformance with sound limitations as required in the California Building Code .
309.6 Dead Legs. Dead legs shall have a method of flushing.
310.0 Prohibited Fittings and Practices.
310.1 Fittings. No double hub fitting, single or double tee branch, single or double tapped tee branch, side inlet quarter bend, running thread, band, or saddle shall be used as a drainage fitting.
310.2 Drainage and Vent Piping. No drainage or vent piping shall be drilled and tapped for the purpose of making connections thereto, and no cast-iron soil pipe shall be threaded.
310.3 Waste Connection. No waste connection shall be
made to a closet bend or stub of a water closet or similar fix ture.
CMC § 4.6 High relevance — show source text
Considerations are soil density; clearance from obstacles, utilities, and structures; location of bends, and water service locations. Excavations and shoring shall be in accordance with jurisdictional safety requirements. (c) Set Up Fuse the proper length of polyethylene pipe in accordance with ASTM F2620, or ASTM D3261 and fuse the end to a small length that is attached to the pulling head. A rod pusher cable is pushed through the damaged host pipe and attached to the pulling cable, which is then drawn through the pipe. The clevis end of the cable is attached to the pulling head. The pulling equipment is then set up according to the manufacturer’s instructions.
(d) Pulling Pull the pulling head through. Once the pull is done, complete the connection to the existing piping.
4.6 Cleanouts
4.6.1 Plug Each cleanout fitting for cast-iron pipe shall consist of a cast-iron or brass body and an approved plug. Each cleanout for galvanized wrought-iron, galvanized steel, copper, or brass pipe shall consist of a brass plug as specified in Table 1, or a standard weight brass cap, or an approved ABS or PVC plastic plug, or an approved stainless-steel cleanout or plug. Plugs shall have raised square heads or approved countersunk rectangular slots. 4.6.2 Approved Each cleanout fitting and each cleanout plug, or cap shall be of an approved type.
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IS 26
4.6.3 Watertight and Gastight
Cleanouts shall be designed to be watertight and gastight.
5 Testing and Inspection Requirements
5.1 Media
The piping of the building sewer shall be tested with water. The Authority Having Jurisdiction shall be permitted to require the removal of cleanouts, etc., to ascertain whether the pressure has reached all parts of the system.
5.2 Water Test
The system shall be tested by plugging the end of the building sewer at its points of connection to the public sewer or private sewage disposal system and completely filling the building sewer with water from the lowest to the highest point thereof.
5.3 Inspections
The completed piping shall be internally inspected by camera unless waived by the Administrative Authority.
TABLE 1
CLEANOUTS (See Section 4.6.1)
NPS SIZE OF CLEANOUT
(inches)THREADS PER INCH 1.5 1.5 11.5
21.5 11.5
2.52.5 8
32.5 8
4 & larger3.5 8 Note: For SI units: 1 inch = 25 mm
Uniform Plumbing Code References
The following sections of the 2024 Uniform Plumbing Code apply.
105.2 Required Inspections
105.2.2 Other Inspections
105.3 Testing of Systems
301.2 Minimum Standards
309.0 Workmanship
312.0 Protection of Piping, Materials, and Structures
CMC § 1716.5 High relevance — show source text
1716.5 Bypass . . . . . . . . . . . . . . . . . . . . . 356
1716.6 Metering . . . . . . . . . . . . . . . . . . . . 356
1717.0 ATL Distributed Energy Systems Design Requirements . . 356
1717.1 Thermal Resources . . . . . . . . . . . 356
1717.2 District Load Profiles. . . . . . . . . . . 357
CHAPTER 18 REFERENCED STANDARDS . . . 359
1801.0 General. . . . . . . . . . . . . . . . . . . . . 361
1801.1 Standards . . . . . . . . . . . . . . . . . . . 361
Table 1801.1 Referenced Standards . . . . . . . . . 361
1801.2 Standards, Publications Practices, and Guides . . . . . . . . . 378
Table 1801.2 Standards, Publications Practices, and Guides . . . . . . . . . 378
xlvi
APPENDICES TABLE OF CONTENTS. . . . . . . . 385
Appendix A Residential Plans Examiner Review Form for HVAC
System Design . . . . . . . . . . . . . . . 387
Appendix B Procedures to be Followed to Place Gas Equipment in Operation . . . . . . . . . . . . . . . . . . . 391
Appendix C Installation and Testing of Oil (Liquid) Fuel-Fired Equipment . . . 395
Appendix D Fuel Supply: Manufactured/Mobile Home Parks and Recreational
Vehicle Parks . . . . . . . . . . . . . . . . 403
Appendix E Sustainable Practices . . . . . . . . . . 411
Appendix F Sizing of Venting Systems and Outdoor Combustion and
Ventilation Opening Design . . . . . 533
Appendix G Example Calculation of Outdoor Air Rate. . . . . . . . . . . . . . 545
Appendix H Professional Qualifications . . . . . . 549
Appendix I Indoor Horticultural Facilities . . . . 553
Appendix J Clean Air Delivery. . . . . . . . . . . . . 559
USEFUL TABLES . . . . . . . . . . . . . . . . . . . . . . . . . . . 563
INDEX . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 571
HISTORY NOTE
APPENDIX . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 593
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CALIFORNIA MECHANICAL CODE – MATRIX ADOPTION TABLE
CHAPTER 1 – ADMINISTRATION
(Matrix Adoption Tables are non-regulatory, intended only as an aid to the code user. See Chapter 1 for state agency authority and building applications.)
|Adopting
CMC § 1.8.3.2.3 High relevance — show source text
Exception: Mobilehome parks where the Depart- ment of Housing and Community Development is the enforcing agency.
1.8.3.2.3 Special Occupancy Parks Act. Refer to the Special Occupancy Parks Act, California Health and Safety Code, Division 13, Part 2.3, commencing with Section 18860 and California Code of Regulations, Title 25, Division 1, Chapter 2.2, commencing with Section 2000 for special occupancy park adminis- trative and enforcement authority, permits, fees, vio- lations, inspections, and penalties both within and outside of special occupancy parks.
Exception: Special occupancy parks where the Department of Housing and Community Develop- ment is the enforcing agency.
1.8.3.2.4 Employee Housing Act. Refer to the Employee Housing Act, California Health and Safety Code, Division 13, Part 1, commencing with Section 17000 and California Code of Regulations,
Title 25, Division 1, Chapter 1, Subchapter 3, com- mencing with Section 600 for employee housing administrative and enforcement authority, permits, fees, violations, inspections, and penalties.
1.8.3.2.5 Factory-Built Housing Law. Refer to the Factory-Built Housing Law, California Health and Safety Code, Division 13, Part 6 commencing with Section 19960 and California Code of Regulations, Title 25, Division 1, Chapter 3, Subchapter 1, com- mencing with Section 3000 for factory-built housing administrative and enforcement authority, permits, fees, violations, inspections, and penalties.
1.8.4 Permits, Fees, Applications, and Inspections.
1.8.4.1 Permits. A written construction permit shall be obtained from the enforcing agency prior to the erection, construction, reconstruction, installation, relocation, or alteration of any plumbing system.
Exceptions:
1. Work exempt from permits as specified in Chapter 1, Administration, Division II, Section 104.2 items (1)-(2) of this code.
2. Changes, alterations, or repairs of a minor nature not affecting structural features, egress, sanitation, safety, or accessibility as determined by the enforc- ing agency.
3. Retroactive permits issued in accordance with Health and Safety Code Section 17958.12.
Exemptions from permit requirements shall not be deemed to grant authorization for any work to be done in any manner in violation of other provisions of law or this code.
CMC § 2303.2.6.1 High relevance — show source text
2303.2.6.1
D5643/D5643M—2006(2018): Specification for Coal Tar Roof Cement, Asbestos-Free
Table 1507.10.2
D5664—2017: Test Methods for Evaluating the Effects of Fire-Retardant Treatments and Elevated Temperatures on Strength Properties of Fire-Retardant-Treated Lumber
2303.2.6.2
D5665/D5665M—99a(2021): Specification for Thermoplastic Fabrics Used in Cold-Applied Roofing and Waterproofing
Table 1507.10.2
D5726—98(2020): Specification for Thermoplastic Fabrics Used in Hot-Applied Roofing and Waterproofing
Table 1507.10.2
D5778—20: Standard Test Method for Electronic Friction Cone and Piezocone Penetration Testing of Soils
1813, 1813A.2
D5878—19: Standard Guides for Using Rock-Mass Classification Systems for Engineering Purposes
1803.5.1
D5882—16: Standard Test Method for Low Strain Impact Integrity Testing of Deep Foundations
1705.10
D6083/D6083M—21: Specification for Liquid Applied Acrylic Coating Used in Roofing Table 1507.10.2, Table 1507.13.3
35-18 2025 CALIFORNIA BUILDING CODE
on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.
REFERENCED STANDARDS
D6162/D6162M—2016: Specification for Styrene Butadiene Styrene (SBS) Modified Bituminous Sheet Materials Using a Combination of Polyester and Glass Fiber Reinforcements
1507.11.2
D6163/D6163M—2016: Specification for Styrene Butadiene Styrene (SBS) Modified Bituminous Sheet Materials Using Glass Fiber Reinforcements
1507.11.2
D6164/D6164M—2016: Specification for Styrene Butadiene Styrene (SBS) Modified Bituminous Sheet Materials Using Polyester Reinforcements
1507.11.2
D6222/D6222M—2016: Specification for Atactic Polypropylene (APP) Modified Bituminous Sheet Materials Using Polyester Reinforcements
1507.11.2
D6223/D6223M—2016: Specification for Atactic Polypropylene (APP) Modified Bituminous Sheet Materials Using a Combination of Polyester and Glass Fiber Reinforcements
1507.11.2
D6298—2016: Specification for Fiberglass Reinforced Styrene-Butadiene-Styrene (SBS) Modified Bituminous Sheets with a Factory Applied Metal Surface
1507.11.2
D6305—21: Practice for Calculating Bending Strength Design Adjustment Factors for Fire-Retardant-Treated Plywood Roof Sheathing
2303.2.6.1
D6380/D6380M—2003(2018): Standard Specification for Asphalt Roll Roofing (Organic Felt) 1507.1.1, Table 1507.1.1(1), 1507.2.8.2, 1507.3.3, 1507.6.5
Frequently asked questions
When is a permit required for mechanical work?
A written construction permit is required before erection, construction, installation, relocation or alteration of mechanical systems under the CMC; see §1.8.4.1 for the permit requirement and exceptions. For specific systems like process piping, the code expressly requires a permit and sets what must be shown on permit documents (§1402.1) .
What inspections and tests are typically required?
Required inspections include rough (before concealment) and final inspections; process piping requires a rough inspection (§1405.2.1) and a final inspection with pressure testing (hydraulic or pneumatic) as described in §1405.2.2. The AHJ must be notified when work is ready for inspection and may require tests to be witnessed and held for specified times .
What rules govern placing gas- or fuel-fired equipment into operation?
The CMC and its appendices provide start‑up and operation procedures; the AHJ must be notified before placing equipment into service and Appendix B contains procedures to follow for placing gas equipment in operation (appendix guidance for safe commissioning, plus Appendix C for oil‑fired equipment) .
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