1602.2 Liquid-Fueled Engines and

Gas Turbines . . . . . . . . . . . . . . . . 343

1602.3 Stationary Engine Generators . . . 343

CHAPTER 17 GEOTHERMAL ENERGY

SYSTEMS AND AMBIENT

TEMPERATURE LOOPS. . . . . . . 345

Part I General . . . . . . . . . . . . . . . . . . . . 347

1701.0 General. . . . . . . . . . . . . . . . . . . . . 347

1701.1 Applicability. . . . . . . . . . . . . . . . . . 347

1701.2 Construction Documents . . . . . . . 347

1701.3 Site Survey . . . . . . . . . . . . . . . . . . 347

1701.4 Used Materials . . . . . . . . . . . . . . . 347

1701.5 Contact with Building Material . . . 347

1701.6 Strains and Stresses . . . . . . . . . . 347

1701.7 Flood Hazard . . . . . . . . . . . . . . . . 347

1701.8 Pipe Support. . . . . . . . . . . . . . . . . 347

1701.9 Velocities . . . . . . . . . . . . . . . . . . . 347

1701.10 Chemical Compatibility . . . . . . . . . 347

1701.11 Heat Transfer Fluid. . . . . . . . . . . . 347

1702.0 Groundwater Systems . . . . . . . . . 347

1702.1 General. . . . . . . . . . . . . . . . . . . . . 347

Table 1701.11.1 Water Quality . . . . . . . . . . . . . . . . 348

1703.0 Design of Systems . . . . . . . . . . . . 348

1703.1 Ground-Heat Exchanger Design . . . . . . . . . . . . . . . . . . . . . 348

1703.2 Piping and Tubing Materials Standards . . . . . . . . . . . . . . . . . . . 348

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Table 1703.2 Plastic Ground Source

Loop Piping. . . . . . . . . . . . . . . . . . 348

1703.3 Fittings . . . . . . . . . . . . . . . . . . . . . 348

Table 1703.3 Ground Source Loop Pipe Fittings . . . . . . . . . . . . . . . . . 348

1703.4 Underground Piping and Submerged Materials . . . . . . . . . . 348

1703.5 Indoor Piping . . . . . . . . . . . . . . . . 349

1704.0 Heat Pumps . . . . . . . . . . . . . . . . . 349

1704.1 Heat Pump Distribution System . . . . . . . . . . . . . . . . . . . . . 349

1704.2 Circulating Pumps . . . . . . . . . . . . 349

1705.0 Valves. . . . . . . . . . . . . . . . . . . . . . 349

1705.1 Where Required . . . . . . . . . . . . . . 349

1705.2 Heat Exchangers . . . . . . . . . . . . . 349

1705.3 Central Systems . . . . . . . . . . . . . . 349

1705.4 Pressure Vessels . . . . . . . . . . . . . 349

1705.5 Pressure-Reducing Valves . . . . . . 349

1705.6 Equipment and Appliances. . . . . . 349

1705.7 Expansion Tanks . . . . . . . . . . . . . 349

1705.8 Reduced Pressure . . . . . . . . . . . . 350

1706.0 Specific System Components Design . . . . . . . . . . . . . . . . . . . . . 350

1706.1 General. . . . . . . . . . . . . . . . . . . . . 350

Table 1706.1 Heat Pumps . . . . . . . . . . . . . . . . . 350

1706.2 Heat Exchangers . . . . . . . . . . . . . 350

1706.3 Heat-Transfer Medium . . . . . . . . . 350

1706.4 Insulation . . . . . . . . . . . . . . . . . . . 350

1707.0 Installation Practices. . . . . . . . . . . 350

1707.1 Prior to Construction. . . . . . . . . . . 350

1707.2 Equipment, Accessories, Components, and Materials . . . . . 350

1707.3 Construction Documents . . . . . . . 350

1707.4 Site Survey Requirements . . . . . . 350

1707.5 Subsurface Investigation . . . . . . . 350

1707.6 Subsurface Conditions . . . . . . . . . 350

1707.7 Ground-Heat Exchanger Installation Practices. . . . . . . . . . . 350

1707.8 Trenching, Excavation, and Backfill . . . . . . . . . . . . . . . . . . 351

1707.9 Trenches, Tunneling, and Driving . . . . . . . . . . . . . . . . . . 351

1707.10 Excavations and

Open Trenches. . . . . . . . . . . . . . . 351

1707.11 Protection of Piping, Materials, and Structures . . . . . . . 351

1707.12 Sleeves. . . . . . . . . . . . . . . . . . . . . 351

1707.13 Steel Nail Plates . . . . . . . . . . . . . . 351

1707.14 Exterior Piping Protection . . . . . . . 351

1707.15 Heat Pump and Distribution System Installation . . . . . . . . . . . . 351

1707.16 Pressurizing During Installation . . . . . . . . . . . . . . . . . . 351

1707.17 Horizontal Geothermal

Piping - Materials and Methods . . 351

1707.18 Trenches, Excavation,

and Backfill . . . . . . . . . . . . . . . . . . 351

1708.0 System Start-Up . . . . . . . . . . . . . . 352

1708.1 General. . . . . . . . . . . . . . . . . . . . . 352

1708.2 Operation and Maintenance Manual . . . . . . . . . . . . . . . . . . . . . 352

1708.3 Labeling and Marking . . . . . . . . . . 352

1708.4 Documentation . . . . . . . . . . . . . . . 352

1708.5 Maintenance . . . . . . . . . . . . . . . . . 352

1708.6 Records . . . . . . . . . . . . . . . . . . . . 352

1708.7 System Start-Up . . . . . . . . . . . . . . 352

1708.8 Contaminants . . . . . . . . . . . . . . . . 352

1709.0 Decommissioning and Abandonment . . . . . . . . . . . . . . . . 352

1709.1 General. . . . . . . . . . . . . . . . . . . . . 352

Part II Closed-Loop Systems . . . . . . . . 352

1710.0 General. . . . . . . . . . . . . . . . . . . . . 352

1710.1 Applicability. . . . . . . . . . . . . . . . . . 352

1710.2 Piping and Tubing. . . . . . . . . . . . . 352

1710.3 Borehole Piping and Tubing . . . . . 352

1710.4 Underground Fittings . . . . . . . . . . 352

1710.5 Verification . . . . . . . . . . . . . . . . . . 353

1710.6 Vertical Bores . . . . . . . . . . . . . . . . 353

1711.0 Ground-Heat Exchanger Testing . . . . . . . . . . . . . . . . . . . . . 353

1711.1 Testing . . . . . . . . . . . . . . . . . . . . . 353

1711.2 Individual Loop Pressure Testing . . . . . . . . . . . . . . . . . . . . . 353

1711.3 Field Pressure Testing – Final . . . 353

1711.4 Field Flow Testing – Final. . . . . . . 353

Part III Open-Loop Systems . . . . . . . . . . 353

1712.0 General. . . . . . . . . . . . . . . . . . . . . 353

1712.1 Applicability. . . . . . . . . . . . . . . . . . 353

1712.2 Test Wells. . . . . . . . . . . . . . . . . . . 353

1712.3 Installation of Water Wells . . . . . . 354

1712.4 Setbacks. . . . . . . . . . . . . . . . . . . . 354

1713.0 Open Ground Water Systems . . . 354

1713.1 General. . . . . . . . . . . . . . . . . . . . . 354

1713.2 Open-Loop Water Well Drilling Logs . . . . . . . . . . . . . . . . . 354

1713.3 Design Considerations . . . . . . . . . 354

1713.4 Water Wells and Injection Wells. . . 354

TABLE OF CONTENTS

1713.5 Testing and Sampling. . . . . . . . . . 354

1713.6 Disinfection . . . . . . . . . . . . . . . . . . 354

1714.0 Testing and Verification . . . . . . . . 354

1714.1 Pumping Test . . . . . . . . . . . . . . . . 354

1714.2 Retesting . . . . . . . . . . . . . . . . . . . 354

1714.3 Variable Rate Pump Test . . . . . . . 355

1714.4 Constant Rate Pump Test . . . . . . 355

1714.5 Water Level Monitoring. . . . . . . . . 355

1714.6 Injection Wells . . . . . . . . . . . . . . . 355

1714.7 Re-Injected Water. . . . . . . . . . . . . 355

Part IV Direct Exchange (DX) Systems . . . . . . . . . . . . . . . . . . . . 355

1715.0 Direct Exchange (DX) Systems . . . . . . . . . . . . . . . . . . . . 355

1715.1 General. . . . . . . . . . . . . . . . . . . . . 355

1715.2 Applicability. . . . . . . . . . . . . . . . . . 355

1715.3 DX Systems . . . . . . . . . . . . . . . . . 355

1715.4 DX System Testing. . . . . . . . . . . . 355

1715.5 Indoor Piping . . . . . . . . . . . . . . . . 355

1715.6 On Site Storage . . . . . . . . . . . . . . 355

1715.7 System Start-Up . . . . . . . . . . . . . . 355

1715.8 DX Piping . . . . . . . . . . . . . . . . . . . 355

Part V Geothermal Ambient

Temperature Loops (ATL) . . . . . 355

1716.0 Ambient Temperature Loop (ATL) Distributed Energy Systems . . . . . . . . . . . . . . 355

1716.1 General. . . . . . . . . . . . . . . . . . . . . 355

1716.2 Permitting . . . . . . . . . . . . . . . . . . . 356

1716.3 Ambient Loop Temperature Range . . . . . . . . . . . . . . . . . . . . . . 356

1716.4 Shutoff Valve . . . . . . . . . . . . . . . . 356

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

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

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.)

CALIFORNIA MECHANICAL CODE – MATRIX ADOPTION TABLE

CHAPTER 1 – ADMINISTRATION (continued) (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.)

This state agency does not adopt sections identified with the following symbol: The Office of the State Fire Marshal’s adoption of this chapter or individual sections is applicable to structures regulated by other state agencies pursuant to Section 1.11.0.

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DIVISION I CALIFORNIA ADMINISTRATION

1.1.0 General.

1.1.1 Title. These regulations shall be known as the California Mechanical Code, may be cited as such and will be referred to herein as “this code.” The California Mechanical Code is Part 4 of thirteen parts of the official compilation and publi- cation of the adoption, amendment, and repeal of mechanical regulations to the California Code of Regulations, Title 24, also referred to as the California Building Standards Code. This part incorporates by adoption the 2024 Uniform Mechan- ical Code of the International Association of Plumbing and Mechanical Officials with necessary California amendments.

icial compilation and publi-_ cation of the adoption, amendment, and repeal of mechanical regulations to the California Code of Regulations, Title 24, also referred to as the California Building Standards Code. This part incorporates by adoption the 2024 Uniform Mechan- ical Code of the International Association of Plumbing and Mechanical Officials with necessary California amendments.

1.1.2 Purpose. The purpose of this code is to establish the minimum requirements to safeguard the public health, safety and general welfare through structural strength, means of egress facilities, stability, access to persons with disabilities, sanitation, adequate lighting and ventilation, and energy conservation; safety to life and property from fire and other hazards attributed to the built environment; and to provide safety to fire fighters and emergency responders during emer- gency operations.

1.1.3 Scope. The provisions of this code shall apply to the construction, alteration, movement, enlargement, replace- ment, repair, equipment, use and occupancy, location, main- tenance, removal, and demolition of every building or structure or any appurtenances connected or attached to such buildings or structures throughout the State of California.

1.1.3.1 Nonstate-Regulated Buildings, Structures, and Applications. Except as modified by local ordinance pursuant to Section 1.1.8, the following standards in the California Code of Regulations, Title 24, Parts 2, 2.5, 3, 4, 5, 6, 7, 9, 10 and 11 shall apply to all occupancies and applications not regulated by a state agency.

1.1.3.2 State-Regulated Buildings, Structures, and Applications. The model code, state amendments to the model code, and/or state amendments where there are no relevant model code provisions shall apply to the following buildings, structures, and applications regu- lated by state agencies as specified in Sections 1.2.0 through 1.14.0, except where modified by local ordinance pursuant to Section 1.1.8. When adopted by a state agency, the provisions of this code shall be enforced by the appropriate enforcing agency, but only to the extent of authority granted to such agency by the state legislature.

Note: See “How to Distinguish Between Model Code Language and California Amendments” in the front of the code.

(1) State-owned buildings, including buildings constructed by the Trustees of the California State University, and to the extent permitted by California laws, buildings designed and constructed by the

Regents of the University of California, and regu- lated by the Building Standards Commission. See Section 1.2.0 for additional scope provisions.

(2) Section 1.3.0 is reserved for the Board of State and Community Corrections.

(3) Section 1.4.0 is reserved for the Department of Consumer Affairs.

(4) Section 1.5.0 is reserved for the California Energy Commission.

(5) Section 1.6.0 is reserved for the Department of Food and Agriculture.

(6) Organized camps, laboratory animal quarters, public swimming pools, radiation protection, commissaries serving mobile food preparation vehi- cles, and wild animal quarantine facilities regulated by the Department of Public Health. See Section 1.7.0 for additional scope provisions.

(7) Hotels, motels, lodging houses, apartments, dwellings, dormitories, condominiums, shelters for homeless persons, congregate residences, employee housing, factory-built housing and other types of dwellings containing sleeping accommodations with or without common toilets or cooking facilities. See Section 1.8.2.1.1 for additional scope provisions.

(8) Accommodations for persons with disabilities in buildings containing newly constructed covered multifamily dwellings, new common use areas serving existing covered multifamily dwellings, additions to existing buildings where the addition alone meets the definition of covered multifamily dwellings and new common-use areas serving new covered multifamily dwellings which are regulated by the Department of Housing and Community Development. See Section 1.8.2.1.2 for additional scope provisions.

(9) Permanent buildings and permanent accessory build- ings or structures constructed within mobilehome parks and special occupancy parks regulated by the Department of Housing and Community Development. See Section 1.8.2.1.3 for additional scope provisions.

(10)Accommodations for persons with disabilities regu- lated by the Division of the State Architect. See Section 1.9.1 for additional scope provisions.

(11) Public elementary and secondary schools, commu- nity college buildings and state-owned or state- leased essential service buildings regulated by the Division of the State Architect. See Section 1.9.2 for additional scope provisions.

(12)Reserved for the State Historical Building Safety Board with the Division of the State Architect.

DIVISION I CALIFORNIA ADMINISTRATION

(13)General acute care hospitals, acute psychiatric hospitals, skilled nursing and/or intermediate care facilities, clinics licensed by the Department of Public Health and correctional treatment centers regulated by the Department of Health Care Access and Information/Office of Statewide Hospital Plan- ning and Development. See Section 1.10.0 for addi- tional scope provisions.

(14)Applications regulated by the Office of State Fire Marshal include but are not limited to the following in accordance with Section 1.11.0:

(1) Buildings or structures used or intended for use

as an:

1.1. Asylum, jail, prison.

1.2. Mental hospital, hospital, home for the elderly, children’s nursery, children’s home or institution, school or any similar occu- pancy of any capacity.

1.3. Theater, dancehall, skating rink, audito- rium, assembly hall, meeting hall, night- club, fair building or similar place of assemblage where 50 or more persons may gather together in a building, room, or structure for the purpose of amusement, entertainment, instruction, deliberation, worship, drinking or dining, awaiting transportation, or education.

1.4. Small family day care homes, large family day-care homes, residential facilities and residential facilities for the elderly, resi- dential care facilities.

1.5. State institutions or other state-owned or state-occupied buildings.

1.6. High rise structures.

1.7. Motion picture production studios.

1.8. Organized camps.

1.9. Residential structures.

(2) Tents, awnings, or other fabric enclosures used in connection with any occupancy.

(3) Fire alarm devices, equipment, and systems in connection with any occupancy.

(4) Hazardous materials, flammable, and combustible liquids.

(5) Public school automatic fire detection, alarm, and sprinkler systems.

(6) Wildland-urban interface fire areas.

(15)Section 1.12.0 is reserved for public libraries constructed and renovated using funds from the California Library Construction and Renovation Bond Act of 1988 and regulated by the State Librarian.

(16)Section 1.13.0 is reserved for the Department of Water Resources.

(17)For applications listed in Section 1.9.1 regulated by the Division of the State Architect – Access Compli-

ance, outdoor environments and uses shall be clas- sified according to accessibility uses described in Chapters 11A and 11B.

(18)Section 1.14.0 is reserved for Marine Oil Terminals regulated by the California State Lands Commis- sion.

1.1.4 Appendices. Provisions contained in the appendices of this code shall not apply unless specifically adopted by a state agency or adopted by a local enforcing agency in compliance with Health and Safety Code Section 18901 et. seq. for Building Standards Law, Health and Safety Code Section 17950 for State Housing Law and Health and Safety Code Section 13869.7 for Fire Protection Districts. See Section 1.1.8 of this code.

1.1.5 Referenced Codes. The codes, standards and publica- tions adopted and set forth in this code, including other codes, standards, and publications referred to therein are, by title and date of publication, hereby adopted as standard refer- ence documents of this code. When this code does not specif- ically cover any subject related to building design and construction, recognized architectural, or engineering prac- tices shall be employed. The National Fire Codes, standards, and the Fire Protection Handbook of the National Fire Protection Association are permitted to be used as authori- tative guides in determining recognized fire prevention engi- neering practices.

not specif-_ ically cover any subject related to building design and construction, recognized architectural, or engineering prac- tices shall be employed. The National Fire Codes, standards, and the Fire Protection Handbook of the National Fire Protection Association are permitted to be used as authori- tative guides in determining recognized fire prevention engi- neering practices.

1.1.6 NonBuilding Standards, Orders and Regulations. Requirements contained in the Uniform Mechanical Code, or in any other referenced standard, code or document, which are not building standards as defined in Health and Safety Code Section 18909, shall not be construed as part of the provisions of this code. For nonbuilding standards, orders, and regulations, see other titles of the California Code of Regulations.

1.1.7 Order of Precedence and Use.

1.1.7.1 Differences. In the event of any differences between these building standards and the standard refer- ence documents, the text of these building standards shall

govern.

1.1.7.2 Specific Provisions. Where a specific provision varies from a general provision, the specific provision shall apply.

1.1.7.3 Conflicts. When the requirements of this code conflict with the requirements of any other part of the California Building Standards Code, Title 24, the most restrictive requirements shall prevail.

1.1.7.3.1 Detached One- and Two-Family Dwellings. Detached one- and two-family dwellings, efficiency dwelling units, lodging houses, live/work units, townhouses not more than three stories above grade plane in height with a separate means of egress, and their accessory structures, shall not be required to comply with the California Residential Code if constructed in accordance with the California Building Code.

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DIVISION I CALIFORNIA ADMINISTRATION

1.1.8 City, County, or City and County Amendments, Additions or Deletions. The provisions of this code do not limit the authority of city, county, or city and county governments to establish more restrictive and reasonably necessary differences to the provisions contained in this code pursuant to complying with Section 1.1.8.1. The effective date of amendments, addi- tions, or deletions to this code by a city, county, or city and county filed pursuant to Section 1.1.8.1 shall be the date filed. However, in no case shall the amendments, additions, or dele- tions to this code be effective any sooner than the effective date of this code.

Local modifications shall comply with Health and Safety Code Section 18941.5 for Building Standards Law, Health and Safety Code Section 17958 for State Housing Law or Health and Safety Code Section 13869.7 for Fire Protection Districts.

1.1.8.1 Findings and Filings.

(1) The city, county, or city and county shall make express findings for each amendment, addition, or deletion based upon climatic, topographical, or geological conditions.

Exception: Hazardous building ordinances and programs mitigating unreinforced masonry build- ings.

(2) The city, county, or city and county shall file the amendments, additions or deletions expressly marked and identified as to the applicable findings. Cities, counties, cities and counties, and fire depart- ments shall file the amendments, additions, or dele- tions, and the findings with the California Building Standards Commission at 2525 Natomas Park

Drive, Suite 130, Sacramento, CA 95833.

(3) Findings prepared by fire protection districts shall be ratified by the local city, county, or city and county and filed with the California Department of Housing and Community Development, Division of Codes and Standards, P.O. Box 278180, Sacra- mento, CA 95827-8180 or 9342 Tech Center Drive, Suite 500, Sacramento, CA, 95826-2582.

1.1.8.2 California Energy Code Requirements for Locally Adopted Energy Standards. In addition to the provisions of Section 1.1.8.1 of this part, local jurisdic- tions that adopt changes to energy conservation or insu- lation standards (including energy efficiency measures) may not enforce such changes until the California Energy Commission has made the findings required by Public Resources Code Section 25402.1(h)(2), following the process specified in Section 10-106 of the California Administrative Code.

1.1.9 Effective Date of This Code. Only those standards approved by the California Building Standards Commission that are effective at the time an application for building permit is submitted shall apply to the plans and specifications for, and to the construction performed under, that permit. For the effective dates of the provisions contained in this code, see the History Note page of this code.

Exceptions: (1) [HCD 1 & HCD 2] Retroactive permits issued in accor- dance with Health and Safety Code Section 17958.12.

(2) [HCD 1 & HCD 2] Plans approved by the Department of Housing and Community Development or a Department- approved design approval agency for factory-built housing as defined by Health and Safety Code Section 19971. Approved plans, pursuant to the California Code of Regu- lations, Title 25, Division 1, Chapter 3, Subchapter 1, Article 3, Section 3037 remain valid for a period of 36 months from the date of plan approval.

1.1.10 Availability of Codes. At least one complete copy each of Titles 8, 19, 20, 24, and 25 with all revisions shall be main- tained in the office of the building official responsible for the administration and enforcement of this code. Each state department concerned and each city, county, or city and county shall have an up-to-date copy of the code available for public inspection, see Health and Safety Code Section 18942(e)(1) and (2).

ach_ of Titles 8, 19, 20, 24, and 25 with all revisions shall be main- tained in the office of the building official responsible for the administration and enforcement of this code. Each state department concerned and each city, county, or city and county shall have an up-to-date copy of the code available for public inspection, see Health and Safety Code Section 18942(e)(1) and (2).

1.1.11 Format. This part fundamentally adopts the Uniform Mechanical Code by reference on a chapter-by-chapter basis. When a specific chapter of the Uniform Mechanical Code is not printed in the code and is marked “Reserved”, such chapter of the Uniform Mechanical Code is not adopted as a portion of this code. When a specific chapter of the Uniform Mechanical Code is marked “Not adopted by the State of California” but appears in the code, it may be available for adoption by local ordinance.

Note: Matrix Adoption Tables at the front of each chapter may aid the code user in determining which chapter or sections within a chapter are applicable to buildings under the authority of a specific state agency, but they are not to be considered regulatory.

1.1.12 Validity. If any chapter, section, subsection, sentence, clause, or phrase of this code is for any reason held to be unconstitutional, contrary to statute, exceeding the authority of the state as stipulated by statutes or otherwise inoperative, such decision shall not affect the validity of the remaining portion of this code.

1.2.0 Building Standards Commission.

1.2.1 BSC. Specific scope of application of the agency responsible for enforcement, the enforcement agency, and the specific authority to adopt and enforce such provisions of this code, unless otherwise stated.

(1) State Buildings for All Occupancies.

Application – State buildings (all occupancies), including buildings constructed by the Trustees of the California State University (CSU) and the Regents of the University of California (UC) where no state agency has the authority to adopt building standards applicable to such buildings.

Enforcing Agency – State or local agency specified by the applicable provisions of law.

Authority Cited – Health and Safety Code Section 18934.5.

DIVISION I CALIFORNIA ADMINISTRATION

Reference – Health and Safety Code, Division 13, Part 2.5, commencing with Section 18901.

(2) University of California, California State Universities, and California Community Colleges.

Application – Standards for lighting for parking lots and primary campus walkways at the University of Cali- fornia, California State Universities, and California Community Colleges.

Enforcing Agency – State or local agency specified by the applicable provisions of law.

Authority Cited – Government Code Section 14617.

Reference – Government Code Section 14617.

(3) Existing State-Owned Buildings, including those owned by the University of California and by the Cali- fornia State University – Building seismic retrofit stan- dards including abating falling hazards of structural and nonstructural components and strengthening of building structures. See also Division of the State Architect.

Enforcing Agency – State or local agency specified by the applicable provisions of law.

Authority Cited – Government Code Section 16600.

References – Government Code Sections 16600 through 16604.

(4) Unreinforced Masonry Bearing Wall Buildings.

Application – Minimum seismic strengthening standards for buildings specified in the California Existing Building Code, except for buildings subject to building standards adopted pursuant to Part 1.5 (commencing with Section 17910).

Enforcing Agency – State or local agency specified by the applicable provisions of law.

Authority Cited – Health and Safety Code Section 18934.7.

References – Health and Safety Code Division 13, Part 2.5 commencing with Sections 18901.

1.2.1.1 State Building. For purposes of this code, a “state building” is a structure for which a state agency or state entity has authority to construct, alter, enlarge, replace, repair or demolish.

1.2.1.2 Enforcement. [CSU, UC, Judicial Council & California Department of Corrections and Rehabilita- tion] state agencies or state entities authorized to construct state buildings may appoint a building official who is responsible to the agency for enforcement of the provisions of the California Building Standards Code.

Exception: State buildings regulated by other sections of this code remain the enforcement responsibility of the designated entities.

1.2.1.3 Enforcement, Reserved for DGS.

1.2.1.4 Adopting Agency Identification. The provisions of this code applicable to buildings identified in this section will be identified in the Matrix Adoption Tables under the acronym BSC.

1.2.2 BSC-CG. Specific scope of application of the agency responsible for enforcement, the enforcement agency, and the specific authority to adopt and enforce such provisions of this code, unless otherwise stated.

(1) Green Building Standards for Nonresidential Occu- pancies.

Application – All occupancies where no other state agency has the authority to adopt green building stan- dards applicable to those occupancies.

Enforcing Agency – State or local agency specified by the applicable provisions of law.

Authority Cited – Health and Safety Code Sections 18930.5, 18938 and 18940.5.

Reference – Health and Safety Code, Division 13, Part 2.5, commencing with Section 18901.

(2) Graywater Systems for Nonresidential Occupancies.

Application – The construction, installation, and alter- ation of graywater systems for indoor and outdoor uses in nonresidential occupancies.

Enforcing Agency – State or local agency specified by the applicable provisions of law.

Authority Cited – Health & Safety Code Section 18941.8.

Reference – Health & Safety Code Section 18941.8.

1.2.3 Alternative Materials, Design, and Methods of Construction and Equipment. The provisions of this code are not intended to prevent the installation of any material or to prohibit any design or method of construction not specifically prescribed by this code, provided that any such alternative has been approved. An alternative material, design, or method of construction shall be approved where the building official finds that the proposed design is satisfactory and complies with the intent of the provisions of this code, and that the material, method or work offered is, for the purpose intended, at least the equivalent of that prescribed in this code in quality, strength, effectiveness, fire resistance, durability and safety.

1.2.3.1 Research Reports. Supporting data, where neces- sary to assist in the approval of materials or assemblies not specifically provided for in this code, shall consist of valid research reports from approved sources.

1.2.3.2 Tests. Whenever there is insufficient evidence of compliance with the provisions of this code, or evidence that a material or method does not conform to the require- ments of this code, or in order to substantiate claims for alternative materials or methods, the building official shall have the authority to require tests as evidence of compli- ance to be made at no expense to the jurisdiction. Test methods shall be as specified in this code or by other recog- nized test standards. In the absence of recognized and accepted test methods, the building official shall approve the testing procedures. Tests shall be performed by an approved agency. Reports of such tests shall be retained by the building official for the period required for retention of public records.

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1.3.0 Reserved for Board of State and Community Correc- tions.

1.4.0 Department of Consumer Affairs.

1.4.1 Specific scope of application of the agency responsible for enforcement, the enforcement agency, and the specific authority to adopt and enforce such provisions of this code, unless otherwise stated.

Board of Pharmacy.

Application – Pharmacies.

Enforcing Agency – State or local agency specified by applicable provisions of law.

Authority Cited – Business and Professions Code Section 4005.

References – Business and Professions Code Sections 4005, 4127.7, and 4201.

1.4.2 Adopting Agency Identification. The provisions of this code applicable to buildings identified in this section will be identified in the Matrix Adoption Tables under the acronym CA.

1.5.0 Reserved for California Energy Commission.

1.6.0 Reserved for Department of Food and Agriculture.

1.7.0 California Department of Public Health.

1.7.1 Specific scope of application of the agency responsible for enforcement, the enforcement agency, and the specific authority to adopt and enforce such provisions of this code, unless otherwise stated.

Department of Public Health.

Application – Food establishments.

Enforcing Agency – Department of Health Services and the local health agency.

Authority Cited – Health and Safety Code Sections 110065, 113710, and 131200.

References – Health and Safety Code Sections 110065, 113705, 114140, and 131200.

1.7.2 Adopting Agency Identification. The provisions of this code applicable to buildings identified in this section will be identified in the Matrix Adoption Tables under the acronym DPH.

1.8.0 Department of Housing and Community Development.

[HCD]

1.8.1 Purpose. The purpose of this code is to establish the minimum requirements necessary to protect the health, safety, and general welfare of the occupants and the public by governing the erection, construction, reconstruction, enlarge- ment, conversion, alteration, repair, moving, removal, demo- lition, ventilation, and maintenance or use of heating, ventilating, cooling, refrigeration systems, incinerators, and other miscellaneous heat-producing appliances.

1.8.2 Authority and Abbreviations.

1.8.2.1 General. The Department of Housing and Community Development is authorized by law to prom- ulgate and adopt building standards and regulations for several types of building applications. The applications under the authority of the Department of Housing and Community Development are listed in Sections 1.8.2.1.1 through 1.8.2.1.3.

1.8.2.1.1 Housing Construction.

Application – Hotels, motels, lodging houses, apart- ments, dwellings, dormitories, condominiums, shel- ters for homeless persons, congregate residences, employee housing, factory-built housing, and other types of dwellings containing sleeping accommoda- tions with or without common toilet or cooking facil- ities including accessory buildings, facilities, and uses thereto. Sections of this code which pertain to applications listed in this section are identified using the abbreviation “HCD 1.”

Enforcing Agency – Local building department or the Department of Housing and Community Devel- opment.

Authority Cited – Health and Safety Code Sections 17040, 17920.9, 17921, 17921.5, 17921.6, 17921.10, 17922, 17922.6, 17922.12, 17922.14, 17922.15, 17926, 17927, 17928, 17958.12, 18938.3, 18944.11, and 19990; and Government Code Section 12955.1.

References – Business and Professions Code Divi- sion 5; Health and Safety Code Sections 17000 through 17062.5, 17910 through 17995.5, 18200 through 18700, 18860 through 18874, 18938.6, 18941, 19890, 19891, 19892 and 19960 through 19997; Civil Code Sections 832, 1101.4, 1101.5, 1954.201, 1954.202 and 5551; and Government Code Sections 8698.4, 12955.1 and 12955.1.1. Cali- fornia Code of Regulations, Title 20, Sections 1605.1, 1605.3 and 1607.

1.8.2.1.2 Housing Accessibility.

Application – Covered multifamily dwellings as defined in Chapter 2 of the California Code of Regu- lations, Title 24, Part 2, also known as the California Building Code including, but not limited to, lodging houses, dormitories, timeshares, condominiums, shel- ters for homeless persons, congregate residences, apartments, dwellings, employee housing, factory- built housing, and other types of dwellings containing sleeping accommodations with or without common toilet or cooking facilities.

Sections of this code identified by the abbrevia- tion “HCD 1-AC” require specific accommodations for persons with disabilities as defined in Chapter 2 of the California Building Code. The application of such provisions shall be in conjunction with other requirements of this code and apply only to newly- constructed covered multifamily dwellings as defined in Chapter 2 of the California Building Code. “HCD 1-AC” applications include, but are not limited to, the following:

DIVISION I CALIFORNIA ADMINISTRATION

(1) All newly-constructed covered multifamily dwellings as defined in Chapter 2 of the Cali- fornia Building Code.

(2) New common use areas as defined in Chapter 2 of the California Building Code serving existing covered multifamily dwellings.

(3) Additions to existing buildings, where the addi- tion alone meets the definition of covered multi- family dwellings as defined in Chapter 2 of the California Building Code.

(4) New common use areas serving new covered multifamily dwellings.

(5) Where any portion of a building’s exterior is preserved, but the interior of the building is removed, including all structural portions of floors and ceilings, the building is considered a new building for determining the application of California Building Code, Chapter 11A.

“HCD 1-AC” building standards generally do not apply to public use areas or public accommodations such as hotels and motels, and public housing. Public use areas, public accommodations, and public housing, as defined in Chapter 2 of the Cali- fornia Building Code, are subject to the Division of the State Architect (DSA-AC) in Chapter 11B, and are referenced in Section 1.9.1.

Newly constructed covered multifamily dwellings, which can also be defined as public housing, shall be subject to the requirements of Chapter 11A and Chapter 11B.

Enforcing Agency – Local building department or the Department of Housing and Community Devel- opment.

Authority Cited – Health and Safety Code Sections 17040, 17920.9, 17921, 17921.5, 17921.6, 17921.10, 17922, 17922.6, 17922.12, 17922.14, 17926, 17927, 17928, 17958.12, 18938.3, 18944.11, and 19990; and Government Code Section 12955.1 and 12955.1.1.

References – Health and Safety Code Sections 17000 through 17062.5, 17910 through 17995.5, 18200 through 18700, 18860 through 18874, 18938.6, 18941 and 19960 through 19997; Civil Code Sections 1101.4, 1101.5, 1954.201, 1954.202; and Government Code Sections 12955.1 and 12955.1.1. California Code of Regulations, Title 20, Sections 1605.1, 1605.3 and 1607.

1.8.2.1.3 Permanent Buildings in Mobilehome Parks and Special Occupancy Parks.

Application – Permanent buildings, and permanent accessory buildings or structures, constructed within mobilehome parks and special occupancy parks that are under the control and ownership of the park operator. Sections of this code which pertain to applications listed in this section are iden- tified using the abbreviation “HCD 2.”

Enforcing Agency – The Department of Housing and Community Development, local building depart- ment or other local agency that has assumed respon- sibility for the enforcement of Health and Safety Code, Division 13, Part 2.1, commencing with Section 18200 for mobilehome parks and Health and Safety Code, Division 13, Part 2.3, commencing with Section 18860 for special occupancy parks.

Authority Cited – Health and Safety Code Sections 17040, 17920.9, 17921, 17921.5, 17921.6, 17921.10, 17922, 17922.6, 17922.12, 17922.14, 17922.15, 17926, 17927, 17928, 17958.12, 18552, 18554, 18620, 18630, 18640, 18670, 18690, 18691, 18865, 18871.3, 18871.4, 18873, 18873.1 through 18873.5, 18938.3, 18944.11, and 19990; and Government Code Section 12955.1.

References – Health and Safety Code Sections 17000 through 17062.5, 17910 through 17995.5, 18200 through 18700, 18860 through 18874, 18938.6, 18941, 19890, 19891, 19892 and 19960 through 19997; Civil Code Sections 1101.4, 1101.5 and 1954.201; and Government Code Sections 12955.1 and 12955.1.1. California Code of Regula- tions, Title 20, Sections 1605.1, 1605.3 and 1607; and Title 25, Sections 1042 and 2042.

1.8.3 Local Enforcing Agency.

1.8.3.1 Duties and Powers. The building department of every city, county, or city and county shall enforce all the provisions of law, this code, and the other rules and regu- lations promulgated by the Department of Housing and Community Development pertaining to the installation, erection, construction, reconstruction, movement, enlargement, conversion, alteration, repair, removal, demolition, or arrangement of apartments, condo- miniums, hotels, motels, lodging houses, and dwellings, including accessory buildings, facilities, and uses thereto.

The provisions regulating the erection and construc- tion of dwellings and appurtenant structures shall not apply to existing structures as to which construction is commenced or approved prior to the effective date of these regulations. Requirements relating to use, mainte- nance, and occupancy shall apply to all dwellings and appurtenant structures approved for construction or constructed before or after the effective date of this code.

ion of dwellings and appurtenant structures shall not_ apply to existing structures as to which construction is commenced or approved prior to the effective date of these regulations. Requirements relating to use, mainte- nance, and occupancy shall apply to all dwellings and appurtenant structures approved for construction or constructed before or after the effective date of this code.

For additional information regarding the use and occupancy of existing buildings and appurtenant structures, see California Code of Regulations, Title 25, Division 1, Chapter 1, Subchapter 1, commencing with Section 1.

1.8.3.2 Laws, Rules, and Regulations. Other than the building standards contained in this code, and notwith- standing other provisions of law, the statutory authority and location of the laws, rules, and regulations to be enforced by local enforcing agencies are listed by statute in Sections 1.8.3.2.1 through 1.8.3.2.5.

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 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. 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