CMC · California Mechanical Code

When do Chapter 2 definitions apply?

Summary: For mechanical work in California, always check Chapter 2 first — Chapter 2 definitions control the Mechanical Code unless a section says otherwise; if a term isn’t in Chapter 2, the Mechanical Code points you to other California codes for definitions and finally to ordinary meanings if no code defines the term (see § 201.1, § 201.3, § 201.4)

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Last reviewed: July 6, 2026

What the code requires — 2–4 sentences

Unless a code provision explicitly says otherwise, the definitions in Chapter 2 apply to terms used in the California Mechanical Code. That basic rule is stated in § 201.1. When a term is not defined in the Mechanical Code, the code directs the user to definitions in other California codes where applicable (§ 201.3); if still not defined, the term takes its ordinarily accepted meaning (§ 201.4) .

If a term appears in the Mechanical Code, use the Chapter 2 definition unless the code text or a listed referenced code says to use a different definition. § 201.1

Requirements in detail

Core rule (when Chapter 2 controls)

Bold rule: Chapter 2 definitions apply throughout the Mechanical Code unless a specific provision says otherwise — see § 201.1 .
Practical consequence: you must check Chapter 2 first for a term that appears in a requirement or table before applying external or dictionary meanings.

Where to look next (if CMC Chapter 2 has no definition)

If Chapter 2 does not define the term, the CMC tells you to look to other California codes and referenced documents for a definition — § 201.3 .
If no definition is found in the code or referenced publications, use the ordinarily accepted meaning of the word as the context implies — § 201.4 .

Decision table — which definition to use

Condition (what you find)	Action (which definition governs)	Code reference
The term is defined in CMC Chapter 2	Use the Chapter 2 definition	§ 201.1
Term not in Chapter 2 but appears in another adopted California code (e.g., Building, Fire, Plumbing)	Use the definition from the other California code / referenced document	§ 201.3
Term not defined in CMC or other referenced codes	Use the ordinarily accepted (dictionary/context) meaning	§ 201.4
Code text explicitly defines a term within a chapter or section (special, local, or agency-adopted language)	The chapter/section-specific definition controls for that text (i.e., "unless otherwise stated")	§ 201.1

(When the CMC has been adopted or modified by a state agency or jurisdiction, consult the adoption/matrix notes in the front matter — those adoption notes appear in the code and direct which sections an agency enforces; see the matrix/adoption material in the CMC files for details.)

Exceptions & special cases

"Unless otherwise expressly stated" language: where a chapter or individual section contains its own definitions or a specific statement that a term has a different meaning, that specific text overrides the Chapter 2 entry — i.e., the Chapter 2 rule is the default, not absolute (§ 201.1) .
Cross‑code definitions: the CMC explicitly defers to definitions in other California codes and referenced documents when it does not define a term itself (§ 201.3) . That means, for example, that for terms governed by the California Fire Code those Fire Code definitions will control where called for.
Ordinary-meaning fallback: when neither the CMC nor referenced codes define a term, the code directs use of "ordinarily accepted meanings" as the context implies (§ 201.4) . The CMC text retrieved does not supply a single required dictionary for every case; some other California codes do cite a specific dictionary. If a local adopting document specifies a dictionary or interpretation, follow that local instruction.

If you need a jurisdictional nuance (for example, OSHPD or other state-agency adoptions that alter which sections apply), consult that agency’s adoption matrix or front-matter notes in the CMC—those are part of the code package and can change which sections are effective for that agency .

Common mistakes

Assuming Chapter 2 definitions never change: wrong. Chapter 2 is the default, but explicit in-text definitions and agency adoptions can override the Chapter 2 entry (§ 201.1) .
Pulling a dictionary meaning before checking Chapter 2 or referenced codes: the code prefers its own definitions first; dictionary meanings are a last resort (§ 201.1, § 201.3, § 201.4) .
Applying a definition from a different California code without checking whether the CMC already defines the term: the CMC’s Chapter 2 definition (if present) controls in the Mechanical Code context (§ 201.1) .
Ignoring adoption/matrix notes: some state agencies adopt only portions of the code or adopt with amendments. Those adoption notes can change which definitions apply to that agency’s regulated facilities; always check the adoption tables/front matter for the applicable authority .

Worked example — concrete scenario

Scenario: A plan reviewer sees the word "mechanical room" in a set of mechanical drawings. The reviewer needs to know whether a specific clearance table and ventilation requirement apply.

Step 1 — Check CMC Chapter 2:

Look in Chapter 2 for "mechanical room". If Chapter 2 contains a definition, use it and apply the associated CMC requirements (default per § 201.1) .

Step 2 — If not defined in CMC Chapter 2:

Check other adopted California codes referenced by the CMC (for instance the California Building Code) to see if that code defines "mechanical room". If the Building Code has a definition and the CMC refers you to other codes, use the Building Code’s definition per § 201.3. For example: if the Building Code defines a room type and includes mandatory clearances, that definition governs the meaning of the term for the mechanical requirement .

Step 3 — If still not defined:

Use the ordinarily accepted meaning in the context of the project per § 201.4. For a mechanical-room example that might reasonably mean “a room used primarily for mechanical equipment,” and you would then apply the CMC provisions that reference mechanical rooms using that ordinary meaning .

Numbers in a concrete check:

Suppose the CMC duct-clearance table requires 3 ft clearance around equipment in a “mechanical room.” If the Building Code definition of “mechanical room” requires a fire-rated enclosure for equipment of a particular size, and the equipment exceeds that threshold, the Building Code definition (found using § 201.3) could change the set of required protections. So the reviewer must follow the hierarchy: Chapter 2 → other California codes → ordinary meaning (§ 201.1, § 201.3, § 201.4) .

Related provisions

§ 201 — General (Chapter 2 introduction and scope)
§ 201.1 — Scope: Chapter 2 definitions apply unless otherwise stated (default rule)
§ 201.2 — Interchangeability / rules of construction (tense/gender/number) — helpful when reading definitions; check if present in your adopted code text
§ 201.3 — Terms defined in other codes: when to use definitions from the California Building Code, Fire Code, Plumbing Code, etc.
§ 201.4 — Terms not defined: use ordinarily accepted meanings as the context implies
CMC adoption/matrix and front-matter notes — check the matrix/adoption tables and agency annotations in the CMC front matter for agency-specific modifications to definitions and applicability

Code references

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

CMC § 1-33 Medium relevance — show source text
112 Service Utilities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-33

113 Means of Appeals. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-33

114 Violations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-34

115 Stop Work Order . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-34

CHAPTER 2 DEFINITIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . .2-1

201 General. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-11

202 Definitions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-11

CHAPTER 3 OCCUPANCY CLASSIFICATION AND USE . . . . .3-1

301 Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-3

302 Occupancy Classification and Use Designation . . . . 3-3

303 Assembly Group A . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-3

304 Business Group B. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-5

305 Educational Group E . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-5

306 Factory Group F . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-6

307 High-Hazard Group H . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-7

308 Institutional Group I . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-13

309 Mercantile Group M. . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-14

310 Residential Group R. . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-15

311 Storage Group S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-17

312 Utility and Miscellaneous Group U . . . . . . . . . . . . . . 3-18

313 Laboratories Group L [SFM]. . . . . . . . . . . . . . . . . . . . . . .3-19
CMC § 1-31 Medium relevance — show source text
114 Stop Work Order . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-31

115 Unsafe Structures and Equipment . . . . . . . . . . . . . . 1-31

116 Emergency Measures . . . . . . . . . . . . . . . . . . . . . . . . . . 1-32

117 Demolition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-32

CHAPTER 2 DEFINITIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . .2-3

201 General. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-3

202 General Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-3

CHAPTER 3 PROVISIONS FOR ALL COMPLIANCE

METHODS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-3

301 Administration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-3

302 General Provisions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-4

303 Storm Shelters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-4

304 Structural Design Loads and Evaluation and Design Procedures. . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-5

305 In-Situ Load Tests . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-6

306 Accessibility for Existing Buildings . . . . . . . . . . . . . . . 3-6

307 Smoke Alarms. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-6

308 Carbon Monoxide Detection . . . . . . . . . . . . . . . . . . . . . 3-6

309 Additions and Replacements of Exterior Wall Coverings and Exterior Wall Envelopes . . . . . . . . . 3-7

310 [OSHPD 1R, 2 and 5] Services/Systems and Utilities. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-7

311 [OSHPD 1R, 2 and 5] Means of Egress . . . . . . . . . . . . . . . 3-7
CMC § 2-5 Medium relevance — show source text
CHAPTER 2 DEFINITIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-5

201 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-5

202 General Definitions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-5

203 Occupancy Classification and Use . . . . . . . . . . . . . . . 2-40

CHAPTER 3 GENERAL REQUIREMENTS. . . . . . . . . . . . . . . . 3-3

301 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-3

302 Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-4

303 Asphalt Kettles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-4 304 Combustible Waste Material . . . . . . . . . . . . . . . . . . . . . .3-4

305 Ignition Sources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-6 306 Motion Picture Projection Rooms and Film . . . . . . . . .3-7 307 Open Burning, Recreational Fires and Portable Outdoor Fireplaces. . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-7 308 Open Flames . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-7 309 Powered Industrial Trucks and Equipment . . . . . . . . .3-9 310 Smoking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-10 311 Vacant Premises . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-10

312 Vehicle Impact Protection . . . . . . . . . . . . . . . . . . . . . . 3-12 313 Fueled Equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-12 314 Indoor Displays . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-12 315 General Storage .
CMC § 1-5 Medium relevance — show source text
102 Construction Documents

and Installation Verification . . . . . . . . . . . . . . . . . . . .1-5

103 Building Standards Commission. . . . . . . . . . . . . . . . . . .1-5 104 Department of Housing and Community Development. . . . . . . . . . . . . . . . . .1-6 105 Division of the State Architect . . . . . . . . . . . . . . . . . . . . .1-6

106 Office of Statewide Health Planning and Development . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-6

CHAPTER 2 DEFINITIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-3

201 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-3

202 Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-3

CHAPTER 3 GREEN BUILDING . . . . . . . . . . . . . . . . . . . . . . . . 3-3

301 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-3

302 Mixed Occupancy Buildings . . . . . . . . . . . . . . . . . . . . . . .3-4 303 Phased Projects. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-4 304 Voluntary Tiers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-4 305 CALGreen Tier 1 and CALGreen Tier 2 . . . . . . . . . . . . . .3-4

306 Voluntary Measures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-4

CHAPTER 4 RESIDENTIAL MANDATORY MEASURES . . . . . . 4-3

4.1 Planning and Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-3 4.2 Energy Efficiency . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-7 4.3 Water Efficiency and Conservation . . . . . . . . . . . . . . . . .4-9 4.4 Material Conservation and Resource Efficiency . . . . 4-11 4.5 Environmental Quality . . . . . . . . . . . . . . . . . . . . . . . . . . 4-13

CHAPTER 5 NONRESIDENTIAL MANDATORY MEASURES . . 5-3

CMC § 1-2 Medium relevance — show source text

CHAPTER TOPICS	Col2
CHAPTER	SUBJECT
1-2	Administration and Definitions
3-4	Wildland-Urban Interface Area Designation and Requirements
5	Building Construction Regulations
6	Fire Protection Requirements
7	Referenced Standards
Appendices A-I	Adoptable and Informational Appendices

Chapter 1 Scope and Administration.

Chapter 1 establishes the limits of applicability of the code and describes how the code is to be applied and enforced. The provisions of Chapter 1 establish the authority and duties of the code official appointed by the authority having jurisdiction and also establish the rights and privileges of the design professional, contractor and property owner.

Chapter 2 Definitions.

Chapter 2 is the repository of the definitions of terms used in the body of the code. The user of the code should be familiar with and consult this chapter because the definitions are essential to the correct interpretation of the code and because the user may not be aware that a term is defined.

Chapter 3 Wildland-Urban Interface Areas.

Chapter 3 provides for the fundamental aspect of applying the code—the legal declaration and establishment of wildland-urban interface areas within the adopting jurisdiction, mapping of the area, periodic review and updates.

Chapter 4 Wildland-Urban Interface Area Requirements.

The requirements of Chapter 4 apply to all occupancies in the wildland-urban interface and pertain to all of the following:

Fire service access to the property that is to be protected, including fire apparatus access roads and off-road driveways.
Premises identification.
Key boxes to provide ready access to properties secured by gated roadways or other impediments to rapid fire service access.
Fire protection water supplies, including adequate water sources, pumper apparatus drafting sites, fire hydrant systems and system reliability.
Fire department access to equipment such as fire suppression equipment and fire hydrants.

Chapter 5 Special Building Construction Regulations.

The regulations in Chapter 5 establish minimum standards for the location, design and construction of buildings and structures based on construction within a Fire Hazard Severity Zone or a Wildland-Urban Interface (WUI) Area.

The construction provisions of Chapter 5 are intended to supplement the requirements of the California Building Code and Califor- nia Residential Code and address mitigation of the unique hazards posed to buildings by wildfire and to reduce the hazards of building fires spreading to wildland fuels. This is accomplished by requiring ignition-resistant construction materials.

Chapter 6 Fire Protection Requirements.

Chapter 6 contains additional requirements for development and construction in Local Responsibility Areas (LRA) designated as Very High Fire Hazard Severity Zones and areas designated by the State Fire Marshal as State Responsibility Areas (SRA). While many of these provisions are found in Title 14 and Title 19 of the California Code of Regulations, they are replicated here for the code user. The local jurisdiction has the authority to apply the same regulations to LRA when the regulations are adopted by local ordinance.

The requirements in this chapter reference the process for adoption of Very High Fire Hazard Severity Zones in the LRA; criteria for evaluating existing subdivisions that are at significant fire risk and are without an adequate secondary egress; and criteria for fire safety provisions required in the Safety Element of a city or county General Plan.

2025 CALIFORNIA WILDLAND-URBAN INTERFACE CODE xi

on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

CMC § 1-24 Medium relevance — show source text
102 Applicability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-24

Part 2—Administration and Enforcement . . . . . . . . . . . . . . . . . 1-24

103 Code Compliance Agency . . . . . . . . . . . . . . . . . . . . . . 1-24

104 Duties and Powers of Building Official. . . . . . . . . . . 1-25

105 Permits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-27

106 Floor and Roof Design Loads . . . . . . . . . . . . . . . . . . . 1-29

107 Construction Documents . . . . . . . . . . . . . . . . . . . . . . 1-29

108 Temporary Structures, Equipment and Systems . . . . . . . . . . . . . . . . . . . . . 1-31

109 Fees . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-31

110 Inspections. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-31

111 Certificate of Occupancy. . . . . . . . . . . . . . . . . . . . . . . 1-33

112 Service Utilities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-33

113 Means of Appeals. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-33

114 Violations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-34

115 Stop Work Order . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-34

CHAPTER 2 DEFINITIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . .2-1

201 General. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-11

202 Definitions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-11

CHAPTER 3 OCCUPANCY CLASSIFICATION AND USE . . . . .3-1

301 Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-3

302 Occupancy Classification and Use Designation . . . . 3-3
CMC § 1-22 Medium relevance — show source text
PART 2—ADMINISTRATION AND ENFORCEMENT . . . . . . . . . . . 1-22

103 Code Compliance Agency . . . . . . . . . . . . . . . . . . . . . . 1-22

104 Duties and Powers of Code Official. . . . . . . . . . . . . . 1-22

105 Permits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-25

106 Construction Documents . . . . . . . . . . . . . . . . . . . . . . 1-26

107 Temporary Uses, Equipment and Systems. . . . . . . 1-28

108 Fees . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-28

109 Inspections. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-28

110 Certificate of Occupancy. . . . . . . . . . . . . . . . . . . . . . . 1-30

111 Service Utilities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-30

112 Means of Appeals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-30

113 Violations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-31

114 Stop Work Order . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-31

115 Unsafe Structures and Equipment . . . . . . . . . . . . . . 1-31

116 Emergency Measures . . . . . . . . . . . . . . . . . . . . . . . . . . 1-32

117 Demolition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-32

CHAPTER 2 DEFINITIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . .2-3

201 General. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-3

202 General Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-3

CHAPTER 3 PROVISIONS FOR ALL COMPLIANCE

METHODS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-3

301 Administration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-3
CMC § 5701.3 Medium relevance — show source text
1. Storage and use of fuel oil in tanks and containers connected to oil-burning equipment. Such storage and use shall be in accordance with Section 605. For abandonment of fuel oil tanks, this chapter applies.
2. Refrigeration systems (see Section 608).
3. Storage and display of aerosol products complying with Chapter 51.
4. Storage and use of liquids that do not have a fire point when tested in accordance with ASTM D92.
5. Liquids with a flash point greater than 95°F (35°C) in a water-miscible solution or dispersion with a water and inert (noncombustible) solids content of more than 80 percent by weight, which do not sustain combustion.
6. Liquids without flash points that can be flammable under some conditions, such as certain halogenated hydrocarbons and mixtures containing halogenated hydrocarbons.
7. The storage of beer, distilled spirits and wines in barrels and casks.
8. Commercial cooking oil storage tank systems located within a building and designed and installed in accordance with Section 607 and NFPA 30.
9. Application and release of pesticide and agricultural products and materials intended for use in weed abatement, erosion control, soil amendment or similar applications where applied in accordance with the manufacturer’s instructions and label directions.
10. The off-site transportation of flammable or combustible liquids where in accordance with Department of Transportation (DOTn) regulation.
5701.3 Referenced documents. The applicable requirements of Chapter 50, other chapters of this code, the California Building Code and the California Mechanical Code pertaining to flammable liquids shall apply.

5701.4 Permits. Permits shall be required as set forth in Sections 105.5 and 105.6.

5701.5 Material classification. Flammable and combustible liquids shall be classified in accordance with the definitions in Chapter 2.

When mixed with lower flash-point liquids, Class II or III liquids are capable of assuming the characteristics of the lower flash-point liquids. Under such conditions, the appropriate provisions of this chapter for the actual flash point of the mixed liquid shall apply.

When heated above their flash points, Class II and III liquids assume the characteristics of Class I liquids. Under such conditions, the appropriate provisions of this chapter for flammable liquids shall apply.

2025 CALIFORNIA FIRE CODE 57-3

on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

FLAMMABLE AND COMBUSTIBLE LIQUIDS

SECTION 5702—DEFINITIONS

5702.1 Definitions. The following terms are defined in Chapter 2:

ALCOHOL-BASED HAND RUB.

BULK PLANT OR TERMINAL.

BULK TRANSFER.

COMBUSTIBLE LIQUID.

Class II.

Class IIIA.

Class IIIB.

FIRE POINT.

FLAMMABLE LIQUID.

Class IA.

Class IB.

Class IC.

FLASH POINT.

FUEL LIMIT SWITCH.

LIQUID STORAGE ROOM.

LIQUID STORAGE WAREHOUSE.

MOBILE FUELING.

PROCESS TRANSFER.

REFINERY.

REMOTE EMERGENCY SHUTOFF DEVICE.

REMOTE SOLVENT RESERVOIR.

SOLVENT DISTILLATION UNIT.

TANK, PRIMARY.

TANK IN AN UNDERGROUND AREA.

SECTION 5703—GENERAL REQUIREMENTS

CMC § 1.11. Medium relevance — show source text

Agency	BSC	BSC- CG	SFM	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- CG	SFM	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													X			X
Adopt Entire Chapter as amended (amended sections listed below)	X			X	X					X	X	X		X	X
Adopt only those sections that are listed below			X			X		X	X
Chapter / Section
REROOFING			X
ROOF COATING			X
ROOF RECOVER			X
ROOF REPAIR			X
ROOF REPLACEMENT			X
SPC SEISMIC SEPARATION										X	X
SUBSTANDARD BUILDING				X	X
SUBSTANTIAL STRUCTURAL DAMAGE										X	X
UNREINFORCED CONCRETE										X	X	X		X	X
UNREINFORCED MASONRY										X	X	X		X	X
UNSAFE			X	X	X
VOLUNTARY STRUCTURAL IMPROVEMENTS										X	X	X		X	X
WORK AREA			X

The 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.

2-2 2025 CALIFORNIA EXISTING BUILDING CODE

on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

2 DEFINITIONS

User notes:

About this chapter: Codes, by their very nature, are technical documents. Every word, term and punctuation mark can add to or change the meaning of a technical requirement. It is necessary to maintain a consensus on the specific meaning of each term contained in the code. Chapter 2 performs this function by stating clearly what specific terms mean for the purpose of the code.

SECTION 201—GENERAL

CMC § 1-26 Medium relevance — show source text
108 Fees . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-26

109 Inspections. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-27

110 Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-27

111 Service Utilities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-28

112 Means of Appeals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-28 113 Violations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-28

114 Stop Work Order . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-29 115 Unsafe Structures or Equipment. . . . . . . . . . . . . . . . . 1-29

CHAPTER 2 DEFINITIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-5

201 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-5

202 General Definitions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-5

203 Occupancy Classification and Use . . . . . . . . . . . . . . . 2-40

CHAPTER 3 GENERAL REQUIREMENTS. . . . . . . . . . . . . . . . 3-3

301 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-3

302 Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-4

303 Asphalt Kettles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-4 304 Combustible Waste Material . . . . . . . . . . . . . . . . . . . . . .3-4
CMC § 1-4 Medium relevance — show source text
1.11 Office of the State Fire Marshal . . . . . . . . . . . . . . . . . . . 1-4

1.12 Board of Forestry. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-10

DIVISION II SCOPE AND ADMINISTRATION . . . . . . . . . . . . . 1-15

PART 1—GENERAL PROVISIONS. . . . . . . . . . . . . . . . . . . . . . . . . . 1-15

101 Scope and General Requirements. . . . . . . . . . . . . . 1-15

102 Applicability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-16

PART 2—ADMINISTRATION AND ENFORCEMENT . . . . . . . . . . . 1-17

103 Code Compliance Agency . . . . . . . . . . . . . . . . . . . . . 1-17

104 Duties and Powers of the Code Official . . . . . . . . . 1-17

105 Permits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-19

106 Construction Documents . . . . . . . . . . . . . . . . . . . . . 1-20

107 Temporary Uses, Equipment and Systems . . . . . . 1-21

108 Fees . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-21

109 Inspection and Enforcement . . . . . . . . . . . . . . . . . . 1-22

110 Certificate of Completion . . . . . . . . . . . . . . . . . . . . . 1-24

111 Service Utilities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-24

112 Means of Appeals. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-24

113 Stop Work Order . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-25

CHAPTER 2 DEFINITIONS . . . . . . . . . . . . . . . . . . . . . . . . . 2-3

201 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-3

202 Definitions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-3

CHAPTER 3 WILDLAND-URBAN INTERFACE AREAS . . . . 3-3
CMC § 1-21 Medium relevance — show source text
107 Temporary Uses, Equipment and Systems . . . . . . 1-21

108 Fees . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-21

109 Inspection and Enforcement . . . . . . . . . . . . . . . . . . 1-22

110 Certificate of Completion . . . . . . . . . . . . . . . . . . . . . 1-24

111 Service Utilities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-24

112 Means of Appeals. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-24

113 Stop Work Order . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-25

CHAPTER 2 DEFINITIONS . . . . . . . . . . . . . . . . . . . . . . . . . 2-3

201 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-3

202 Definitions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-3

CHAPTER 3 WILDLAND-URBAN INTERFACE AREAS . . . . 3-3

301 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-3

302 Wildland-Urban Interface Area Designations . . . . . .3-3

CHAPTER 4 WILDLAND-URBAN INTERFACE AREA

REQUIREMENTS . . . . . . . . . . . . . . . . . . . . . . 4-3

401 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-3

402 Applicability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-3

403 Access . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-3

404 Water Supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-7

CHAPTER 5 SPECIAL BUILDING CONSTRUCTION

REGULATIONS . . . . . . . . . . . . . . . . . . . . . . . . 5-3

501 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-3
CMC § 201.1 Medium relevance — show source text

Division 1
Section|Gov Code
Section|PRC
Section|HSC
Section| |---|---|---|---|---|---|---|---|---|---|---| |Section|Title|Title|Title|Title|Title|Title|Title|Title|Title|Title| |Chapter 2|Definitions|Definitions|Definitions|Definitions|Definitions|Definitions|Definitions|Definitions|Definitions|Definitions| |201|General|Y||||||||| |201.1|Scope|Y||||||||| |201.2|Interchangeability|Y||||||||| |201.3|Terms defined in
other codes|Y||201.3||||||| |201.4|Terms not defined|Y||||||||| |202|Definitions|Y||||||||| ||Accessory structure|Y||||||||| ||Agriculture (T14)|Y||||1270.01(1)||||| ||Applicable building|Y||702A||||||| ||Approved|Y||||||||| ||Approved agency|Y||||||||| ||Building|Y||||1270.01(c)||||| ||Building (T14)|Y||||||||| ||Building official|Y||||||||| ||Certificate of
completion|Y||||||||| ||Code official|Y||||||||| ||Critical fire weather|Y||||||||| ||Dead-end road (T14)|Y||||1270.01(e)||||| ||Defensible space (T14)|Y||||||||| ||Driveway (T14)|Y||||||||| ||Dwelling|Y||702A||1270.01(i)||||| ||Exterior wall assembly|Y||702A||||||| ||Exterior wall covering|Y||702A||||||| ||Fire chief|Y||||||||| ||Fire code official|Y|||202|||||| ||Fire flow calculation
area|Y||||||||| ||Fire hazard severity
zones|Y||702A|4902.1|||2201||| ||Fire protection plan|Y||702A|4902.1|||||| ||Fire weather|Y||||||||| ||Fire-resistance-rated
construction|Y||||||||| ||Fire-smart vegetation|Y|||4902.1|1271.01||||| ||Flame spread index|Y||||||||| ||Fuel|Y||||||||4291(a)(1)(A)| ||Fuel break_(T14)|Y||||1270.01(n)||||| ||Fuel modification|Y||||||||| ||Fuel mosaic|Y||||||||| ||Fuel-loading|Y||||||||| ||Green belt(T14)|Y||||1270.01(o)||||| ||Greenways (T14)|Y||||1270.01(p)||||| ||Hammerhead/T (T14)|Y||||1270.01(q)||||| ||Hazardous land use
(T14)_|Y||||1270.01(r)||||| ||Hazardous materials|Y||||||||| ||Heavy timber
construction|Y||||||||| ||Ignition-resistant
building material|Y||||||||| ||Local responsibility
area (LRA)|Y||702A|4902.1|||||| ||Log wall construction|Y|||||||||

2025 CALIFORNIA WILDLAND-URBAN INTERFACE CODE APPENDIX H-25
CMC § 1.11. Medium relevance — show source text
REPAIR|||X|||||||||||||||||||||| |ROOF REPLACEMENT|||X|||||||||||||||||||||| |SPC SEISMIC SEPARATION||||||||||X|X|||||||||||||| |SUBSTANDARD BUILDING||||X|X|||||||||||||||||||| |SUBSTANTIAL STRUCTURAL
DAMAGE||||||||||X|X|||||||||||||| |UNREINFORCED CONCRETE||||||||||X|X|X||X|X|||||||||| |UNREINFORCED MASONRY||||||||||X|X|X||X|X|||||||||| |UNSAFE|||X|X|X|||||||||||||||||||| |VOLUNTARY STRUCTURAL
IMPROVEMENTS||||||||||X|X|X||X|X|||||||||| |WORK AREA|||X||||||||||||||||||||||

The 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.

2-2 2025 CALIFORNIA EXISTING BUILDING CODE

on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

2 DEFINITIONS

User notes:

About this chapter: Codes, by their very nature, are technical documents. Every word, term and punctuation mark can add to or change the meaning of a technical requirement. It is necessary to maintain a consensus on the specific meaning of each term contained in the code. Chapter 2 performs this function by stating clearly what specific terms mean for the purpose of the code.

SECTION 201—GENERAL

201.1 Scope. Unless otherwise expressly stated, the following words and terms shall, for the purposes of this code, have the meanings shown in this chapter.

201.2 Interchangeability. Words used in the present tense include the future; words stated in the masculine gender include the feminine and neuter; the singular number includes the plural and the plural, the singular.

201.3 Terms defined in other codes. Where terms are not defined in this code and are defined in the other California Codes, such terms shall have the meanings ascribed to them in those codes. [OSHPD 1, 1R, 2, 4 & 5] For terms not defined in this chapter, refer to Chapters 6 and 7 of the California Administrative Code, and Chapter 2 of the California Building Code. [DSA-SS & DSA-SS/CC] Definitions of terms given in Section 4-207 or 4-314 of the California Administrative Code govern over those in Section 202.

201.4 Terms not defined. Where terms are not defined through the methods authorized by this chapter, such terms shall have ordinarily accepted meanings such as the context implies.

SECTION 202—GENERAL DEFINITIONS

ACCESSORY DWELLING UNIT. [HCD 1 & HCD 2] An attached or detached residential dwelling unit that provides complete independent living facilities for one or more persons and is located on a lot with a proposed or existing primary residence. Accessory dwelling units shall include permanent provisions for living, sleeping, eating, cooking and sanitation on the same parcel as the single-family or multi- family dwelling is or will be situated. (See Government Code Section 65852.2.)
CMC § 104.5 Medium relevance — show source text
For each ventilation system that is not a portion of a heating or air-conditioning system authorized by a permit.........................................................................................................................................._____ [1]

For the installation of each hood that is served by mechanical exhaust, including the ducts for such hood ........................................................................................................................_____ [1]
1. Incinerators:
For the installation or relocation of each domestic-type incinerator...................................................................._____ [1] For the installation or relocation of each commercial or industrial-type incinerator..........................................._____ [1]

2025 CALIFORNIA MECHANICAL CODE 27

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

DIVISION II SCOPE AND ADMINISTRATION

TABLE 104.5 (continued)

MECHANICAL PERMIT FEES
1. Miscellaneous:
For each appliance or piece of equipment regulated by this code, but not classed in other appliance categories, or for which no other fee is listed in this table..................................................................................._____ [1]
1. Fuel Gas Piping:
Where Chapter 13 or Appendix B is applicable (See Section 101.2), permit fees for fuel-gas piping shall be as follows: For each gas piping system of one to five outlets ................................................................................................_____ [1] For each additional gas piping system, per outlet................................................................................................_____ [1]
1. Process Piping: For each hazardous process piping system (HPP) of one to four outlets............................................................._____ [1] For each HPP piping system of five or more outlets, per outlet .........................................................................._____ [1] For each nonhazardous process piping system (NPP) of one to four outlets......................................................._____ [1] For each NPP piping system of five or more outlets, per outlet .........................................................................._____ [1]
Other Inspections and Fees
1. Inspections outside of normal business hours, per hour (minimum charge – 2 hours)..............................................._____ [1]
2. Reinspection fees assessed under provisions of Section 105.2.6, per inspection ......................................................._____ [1]
3. Inspections for which no fee is specifically indicated, per hour (minimum charge – [1] ∕ 2 hour)..................................._____ [1]
4. Additional plan review required by changes, additions, or revisions to plans or to plans for which an initial review has been completed, per hour (minimum charge – [1] ∕ 2 hour).................................................................._____ [1]
For SI units: 1000 British thermal units per hour = 0.293 kW, 1 horsepower = 0.746 kW, 1 cubic foot per minute = 0.00047 m [3] / s

Notes:

1 Jurisdiction will indicate their fees here.

2 This fee shall not apply to an air-handling unit that is a portion of a factory-assembled appliance, cooling unit, evaporative cooler, or absorption unit for which a permit is required elsewhere in this code.

28 2025 CALIFORNIA MECHANICAL CODE

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

CALIFORNIA MECHANICAL CODE – MATRIX ADOPTION TABLE

CHAPTER 2 – DEFINITIONS

(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.)

CMC § 2-1 Medium relevance — show source text

CHAPTER 2 – DEFINITIONS

(Matrix Adoption Tables are nonregulatory, intended only as an aid to the code user. See Chapter 1 for state agency authority and building applications.)

Adopting agency	BSC	BSC- CG	SFM	HCD	Col6	Col7	DSA	Col9	OSHPD	Col11	Col12	Col13	Col14	Col15	BSCC	DPH	AGR	DWR	CEC	CA	SL	SLC
Adopting agency	BSC	BSC- CG	SFM	1	2	1/AC	AC	SS	1	1R	2	3	4	5	5	5	5	5	5	5	5	5
Adopt entire CA chapter		X		X				X
Adopt entire chapter as amended (amended sections listed below)									X		X		X
Adopt only those sections that are listed below
Chapter/Section
201
CALIFORNIA RESIDENTIAL CODE									†		†		†
LOW-RISE RESIDENTIAL BUILDING									†		†		†
PLANTS									†		†		†
RESIDENTIAL BUILDING									†		†		†
RESILIENT FLOORING									†		†		†

The state agency does not adopt sections identified by the following symbol: †.

2025 CALIFORNIA GREEN BUILDING STANDARDS CODE 2-1

on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

2-2 2025 CALIFORNIA GREEN BUILDING STANDARDS CODE

on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

2 DEFINITIONS

SECTION 201—GENERAL

201.1 Scope. Unless otherwise stated, the following words and terms shall, for the purposes of this code, have the meanings shown in this chapter.

201.2 Interchangeability. Words used in the present tense include the future; words stated in the masculine gender include the feminine and neuter; the singular number includes the plural and the plural, the singular.

201.3 Terms defined in other documents. Where terms are not defined in this code and are defined in the California Building Stan- dards Code or other referenced documents, such terms shall have the meanings ascribed to them as in those publications.

201.4 Terms not defined. Where terms are not defined as specified in this section, such terms shall have ordinarily accepted meanings such as the context implies.

SECTION 202—DEFINITIONS

CMC § 1.5 Medium relevance — show source text
The California Code of Regulations (CCR), Title 14, Division 1.5 provisions that are found in the California Wildland-Urban Interface Code are not listed in the Matrix Adoption Tables as they are not within the State Fire Marshal’s authority to adopt. These provisions are a reprint from the current CCR, Title 14, Division 1.5 text for the code user’s convenience only and are identified in the body of the code by square brackets containing references to applicable Title 14 sections.

2025 CALIFORNIA WILDLAND-URBAN INTERFACE CODE 2-1

on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

2-2 2025 CALIFORNIA WILDLAND-URBAN INTERFACE CODE

on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

2 DEFINITIONS

User notes:

About this chapter: Codes, by their very nature, are technical documents. Every word, term and punctuation mark can add to or change the meaning of a technical requirement. It is necessary to maintain a consensus on the specific meaning of each term contained in the code. Chapter 2 performs this function by stating clearly what specific terms mean for the purpose of the code.

SECTION 201—GENERAL

201.1 Scope. Unless otherwise expressly stated, the following words and terms shall, for the purposes of this code, have the meanings shown in this chapter.

201.2 Interchangeability. Words stated in the present tense include the future; words stated in the masculine gender include the feminine and neuter; and the singular number includes the plural and the plural the singular.

201.3 Terms defined in other codes. Where terms are not defined in this code and are defined in the California Building Code, Cali- fornia Existing Building Code, California Fire Code, California Electrical Code, California Mechanical Code or California Plumbing Code, such terms shall have the meanings ascribed to them as in those codes.

201.4 Terms not defined. Where terms are not defined through the methods authorized by this section, such terms shall have their ordinarily accepted meanings such as the context implies.

SECTION 202—DEFINITIONS

ACCESSORY STRUCTURE. A building or structure used to shelter or support any material, equipment, chattel or occupancy other than a habitable building.

AGRICULTURE (applicable to CCR, Title 14 provisions only). Land used for agricultural purposes as defined in a Local Jurisdiction's zoning ordinances. [CCR Title 14 §1270.01(a)]

APPLICABLE BUILDING. A building that has residential, commercial, educational, institutional or similar occupancy type use.

[A] APPROVED. Acceptable to the code official.

[A] APPROVED AGENCY. An established and recognized organization that is regularly engaged in conducting tests, furnishing inspection services or furnishing product evaluation or certification where such organization has been approved by the code official.

[A] BUILDING. Any structure intended for supporting or sheltering any occupancy.

BUILDING (applicable to CCR, Title 14 provisions only). Any Structure used or intended for supporting or sheltering any use or Occupancy, except those classified as Utility and Miscellaneous Group U. [CCR Title 14 §1270.01(c)]
CMC § 203.7.3 Medium relevance — show source text
Title 19, Division 1]||||X|||||||||||||||||||| |Chapter / Section|||||||||||||||||||||||| |203.7.3|||X||||||||||||||||||||| |203.7.3.6 - 203.7.3.8|||X||||||||||||||||||||| |203.7.4|||X||||||||||||||||||||| |203.7.4.1|||X||||||||||||||||||||| |203.9.1|||X||||||||||||||||||||| |203.9.2|||X||||||||||||||||||||| |203.9.2.1|||X||||||||||||||||||||| |203.9.2.2|||X||||||||||||||||||||| |203.9.3|||X||||||||||||||||||||| |203.9.3.3|||X||||||||||||||||||||| |203.9.4|||X||||||||||||||||||||| |203.12|||X||||||||||||||||||||| |203.13|||X|||||||||||||||||||||
- The California Code of Regulations (CCR), Title 19, Division 1 provisions that are found in the California Fire Code are a reprint from the current CCR, Title 19, Division 1 text for the code user’s convenience only. The scope, applicability and appeals procedures of CCR, Title 19, Division I remain the same. The state agency does not adopt sections identified by 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.
2-4 2025 CALIFORNIA FIRE CODE

on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

2 DEFINITIONS

User notes:

About this chapter: Codes, by their very nature, are technical documents. Every word, term and punctuation mark can add to or change the meaning of a technical requirement. It is necessary to maintain a consensus on the specific meaning of each term contained in the code. Chapter 2 performs this function by stating clearly what specific terms mean for the purpose of the code. General definitions are located in Section 202 and occupancy classification definitions are located in Section 203.

SECTION 201—GENERAL

201.1 Scope. Unless otherwise expressly stated, the following words and terms shall, for the purposes of this code, have the meanings shown in this chapter.

201.2 Interchangeability. Words used in the present tense include the future; words stated in the masculine gender include the feminine and neuter; the singular number includes the plural and the plural, the singular.

201.3 Terms defined in other codes. Where terms are not defined in this code and are defined in the California Building Code, Cali- fornia Mechanical Code or California Plumbing Code, such terms shall have the meanings ascribed to them as in those codes.

201.4 Terms not defined. Where terms are not defined through the methods authorized by this section, such terms shall have ordinarily accepted meanings such as the context implies. Merriam Webster’s Collegiate Dictionary, 11th Edition, shall be considered as providing ordinarily accepted meanings.

SECTION 202—GENERAL DEFINITIONS

CMC § 105.2.6 Medium relevance — show source text

Other Inspections and Fees

Inspections outside of normal business hours, per hour (minimum charge – 2 hours)..............................................._____ [1]
Reinspection fees assessed under provisions of Section 105.2.6, per inspection ......................................................._____ [1]
Inspections for which no fee is specifically indicated, per hour (minimum charge – [1] ∕ 2 hour)..................................._____ [1]
Additional plan review required by changes, additions, or revisions to plans or to plans for which an initial review has been completed, per hour (minimum charge – [1] ∕ 2 hour).................................................................._____ [1]

For SI units: 1000 British thermal units per hour = 0.293 kW, 1 horsepower = 0.746 kW, 1 cubic foot per minute = 0.00047 m [3] / s

Notes:

1 Jurisdiction will indicate their fees here.

2 This fee shall not apply to an air-handling unit that is a portion of a factory-assembled appliance, cooling unit, evaporative cooler, or absorption unit for which a permit is required elsewhere in this code.

28 2025 CALIFORNIA MECHANICAL CODE

CALIFORNIA MECHANICAL CODE – MATRIX ADOPTION TABLE

CHAPTER 2 – DEFINITIONS

(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 Adopt Entire Chapter Adopt Entire Chapter as amended (amended sections listed below) Adopt only those sections that are listed below Chapter/Section 203.0 204.0 206.0 207.0 208.0 209.0 210.0 214.0 215.0 216.0 217.0 222.0 223.0 228.0	BSC	BSC- CG	SFM	HCD	Col6	Col7	DSA	Col9	Col10	OSHPD	Col12	Col13	Col14	Col15	Col16	Col17	BSCC	DPH	AGR	DWR	CEC	CA	SL	SLC
Adopting Agency Adopt Entire Chapter Adopt Entire Chapter as amended (amended sections listed below) Adopt only those sections that are listed below Chapter/Section 203.0 204.0 206.0 207.0 208.0 209.0 210.0 214.0 215.0 216.0 217.0 222.0 223.0 228.

CMC § 1.11. Medium relevance — show source text
- The California Code of Regulations (CCR), Title 19, Division 1 provisions that are found in the California Fire Code are a reprint from the current CCR, Title 19, Division 1 text for the code user’s convenience only. The scope, applicability and appeals procedures of CCR, Title 19, Division I remain the same. The state agency does not adopt sections identified by 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.
2025 CALIFORNIA FIRE CODE 30-1

on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

30-2 2025 CALIFORNIA FIRE CODE

on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

30 INDUSTRIAL OVENS

User notes:

About this chapter: Chapter 30 addresses the fuel supply, ventilation, emergency shutdown equipment, fire protection and the operation and maintenance of industrial ovens, which are sometimes referred to as industrial heat enclosures or industrial furnaces. Compliance with this chapter is intended to reduce the likelihood of fires involving industrial ovens, which are usually the result of the fuel in use or volatile vapors given off by the materials being heated, or to manage the impact if a fire should occur.

SECTION 3001—GENERAL

3001.1 Scope. This chapter shall apply to the installation and operation of industrial ovens and furnaces. Industrial ovens and furnaces shall comply with the applicable provisions of the International Fuel Gas Code, the California Mechanical Code, NFPA 86, and this chapter. The terms “ovens” and “furnaces” are used interchangeably in this chapter.

3001.2 Permits. Permits shall be required as set forth in Sections 105.5 and 105.6.

SECTION 3002—DEFINITIONS

3002.1 Definitions. The following terms are defined in Chapter 2:

FURNACE CLASS A.

FURNACE CLASS B.

FURNACE CLASS C.

FURNACE CLASS D.

SECTION 3003—LOCATION

3003.1 Ventilation. Enclosed rooms or basements containing industrial ovens or furnaces shall be provided with combustion air in accordance with the International Fuel Gas Code and the California Mechanical Code, and with ventilation air in accordance with the California Mechanical Code .

3003.2 Exposure. When locating ovens, oven heaters and related equipment, the possibility of fire resulting from overheating or from the escape of fuel gas or fuel oil and the possibility of damage to the building and injury to persons resulting from explosion shall be considered.

3003.3 Ignition source. Industrial ovens and furnaces shall be located so as not to pose an ignition hazard to flammable vapors or mists or combustible dusts.

3003.4 Temperatures. Roofs and floors of ovens shall be insulated and ventilated to prevent temperatures at combustible ceilings and floors from exceeding 160°F (71°C).

SECTION 3004—FUEL PIPING

3004.1 Fuel-gas piping. Fuel-gas piping serving industrial ovens shall comply with the International Fuel Gas Code . Piping for other fuel sources shall comply with this section.
CMC § 1.11. Medium relevance — show source text
Way_||||||X|X|||||||||||||||||| |Waiting Room|||X|||||||||||||||||||||| |Walk||||||X|X|||||||||||||||||| |Waterline||||||||||||||||||X||||||| |Wet Bar|||||||X|||||||||||||||||| |Wheelchair||||||X|X|||||||||||||||||| |Wheelchair Space|||||||X|||||||||||||||||| |Winery Caves|||X|||||||||||||||||||||| |Work Area Equipment|||||||X|||||||||||||||||| |Workstation_ (2nd paragraph_
only)|||||||X||||||||||||||||||

The state agency does not adopt sections identified by 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.

2-10 2025 CALIFORNIA BUILDING CODE

on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

2 DEFINITIONS

User notes:

About this chapter: Codes, by their very nature, are technical documents. Every word, term and punctuation mark can add to or change the meaning of a technical requirement. It is necessary to maintain a consensus on the specific meaning of each term contained in the code. Chapter 2 performs this function by stating clearly what specific terms mean for the purposes of the code.

ICC code development note: Code change proposals to sections preceded by the designation [A], [BG] or [BS] will be considered by one of the code development committees meeting during the 2025 (Group B) Code Development Cycle.

SECTION 201—GENERAL

201.1 Scope. Unless otherwise expressly stated, the following words and terms shall, for the purposes of this code, have the meanings shown in this chapter.

201.2 Interchangeability. Words used in the present tense include the future; words stated in the masculine gender include the feminine and neuter; the singular number includes the plural and the plural, the singular.

201.3 Terms defined in other codes. Where terms are not defined in this code and are defined in the California Energy Code, Califor- nia Existing Building Code, California Fire Code, California Green Building Standards Code, California Electrical Code, California Mechanical Code or California Plumbing Code, such terms shall have the meanings ascribed to them as in those codes.

201.4 Terms not defined. Where terms are not defined through the methods authorized by this section, such terms shall have ordinarily accepted meanings such as the context implies.

For applications listed in Section 1.11 regulated by the Office of the State Fire Marshal, where terms are not defined through the meth- ods authorized by this section, such terms shall have ordinarily accepted meanings such as the context implies. Webster’s Third New International Dictionary of the English Language, Unabridged, shall be considered as providing ordinarily accepted meanings.

SECTION 202—DEFINITIONS

[BG] 24-HOUR BASIS. The actual time that a person is an occupant within a facility for the purpose of receiving care. It shall not include a facility that is open for 24 hours and is capable of providing care to someone visiting the facility during any segment of the 24 hours.

[BS] AAC MASONRY. Masonry made of autoclaved aerated concrete (AAC) units, manufactured without internal reinforcement and bonded together using thin- or thick-bed mortar.
CMC § 901.1 Medium relevance — show source text
901.1 Applicability. . . . . . . . . . . . . . . . . . 199

902.0 General. . . . . . . . . . . . . . . . . . . . . 199

902.1 Nonindustrial Appliances . . . . . . . 199

902.2 Combustion Air from Bedroom

or Bathroom . . . . . . . . . . . . . . . . . 199

902.3 Added or Converted Appliances. . 199

902.4 Type of Gas(es) . . . . . . . . . . . . . . 199

902.5 Safety Shutoff Devices for Unlisted LP-Gas Appliances Used Indoors . . . . . . . . . . . . . . . . 199

902.6 Fuel Input Rate . . . . . . . . . . . . . . . 199

902.7 Use of Air or Oxygen Under Pressure . . . . . . . . . . . . . . . . . . . . 199

902.8 Appliance Support . . . . . . . . . . . . 199

902.9 Flammable Vapors . . . . . . . . . . . . 199

902.10 Solid-Fuel-Burning Appliances . . . 199

902.11 Combination of Appliances and Equipment . . . . . . . . . . . . . . . 199

902.12 Protection of Gas Appliances from Fumes or Gases Other

than Products of Combustion . . . . 199

902.13 Process Air . . . . . . . . . . . . . . . . . . 200

902.14 Gas Appliance Pressure Regulators . . . . . . . . . . . . . . . . . . 200

902.15 Bleed Lines for Diaphragm-Type Valves. . . . . . . . . . . . . . . . . . . . . . 200

903.0 Air-Conditioning Appliances . . . . . 200

903.1 Electric Air Conditioners . . . . . . . . 200

903.2 Gas-Fired Air Conditioners

and Heat Pumps. . . . . . . . . . . . . . 200

903.3 Packaged Terminal Air Conditioners . . . . . . . . . . . . . . . . . 200

904.0 Central Heating Boilers and Furnaces. . . . . . . . . . . . . . . . . . . . 200

904.1 Application . . . . . . . . . . . . . . . . . . 200

2025 CALIFORNIA MECHANICAL CODE

904.2 Location . . . . . . . . . . . . . . . . . . . . 201

904.3 Clearance . . . . . . . . . . . . . . . . . . . 201

904.4 Assembly and Installation. . . . . . . 201

904.5 Temperature or Pressure Limiting Devices . . . . . . . . . . . . . . 202

904.6 Low-Water Cutoff . . . . . . . . . . . . . 202

904.7 Steam Safety and Pressure Relief Valves. . . . . . . . . . . . . . . . . 202

904.8 Refrigeration Coils . . . . . . . . . . . . 202
CMC § 6.44 Medium relevance — show source text
17|6.44|6.66|6.99|7.23|7.40| |45|75|30|6.08|6.34|6.54|6.84|7.06|7.22| |44|75|31|6.00|6.24|6.43|6.71|6.90|7.05| |43|75|32|5.91|6.15|6.33|6.58|6.76|6.89| |42|75|33|5.83|6.07|6.23|6.47|6.63|6.75| |41|75|34|5.74|5.98|6.14|6.36|6.51|6.62| |46|80|34|5.74|5.98|6.14|6.36|6.51|6.62| |40|75|35|5.65|5.90|6.05|6.26|6.40|6.51| |45|80|35|5.65|5.90|6.05|6.26|6.40|6.51| |44|80|36|5.56|5.81|5.97|6.17|6.30|6.40| |43|80|37|5.46|5.73|5.89|6.08|6.21|6.30| |42|80|38|5.35|5.64|5.80|6.00|6.12|6.20| |41|80|39|5.23|5.54|5.71|5.91|6.03|6.11| |46|85|39|5.23|5.54|5.71|5.91|6.03|6.11| |40|80|40|5.10|5.44|5.62|5.83|5.95|6.03| |45|85|40|5.10|5.44|5.62|5.83|5.95|6.03| |44|85|41|4.96|5.33|5.55|5.74|5.86|5.94| |43|85|42|4.81|5.21|5.42|5.66|5.78|5.86| |42|85|43|4.63|5.08|5.31|5.56|5.69|5.77| |41|85|44|4.45|4.93|5.19|5.46|5.60|5.69| |40|85|45|4.24|4.77|5.06|5.35|5.50|5.59| |Condenser DT2|Condenser DT2|Condenser DT2|14.04|11.23|9.36|7.02|5.62|4.68| |1. LIFT = Entering Condenser Water Temperature (°F) – Leaving Chilled Water Temperature (°F)
2.
CMC § 7.47 Medium relevance — show source text
15|7.47|7.72|8.10|8.37|8.58| |45|75|30|7.05|7.35|7.58|7.93|8.18|8.36| |44|75|31|6.95|7.23|7.45|7.77|8.00|8.16| |43|75|32|6.85|7.13|7.33|7.63|7.83|7.98| |42|75|33|6.75|7.03|7.22|7.49|7.68|7.82| |41|75|34|6.65|6.93|7.12|7.37|7.55|7.67| |46|80|34|6.65|6.93|7.12|7.37|7.55|7.67| |40|75|35|6.55|6.83|7.01|7.26|7.42|7.54| |45|80|35|6.55|6.83|7.01|7.26|7.42|7.54| |44|80|36|6.44|6.73|6.92|7.15|7.30|7.41| |43|80|37|6.32|6.63|6.82|7.05|7.19|7.30| |42|80|38|6.20|6.53|6.72|6.95|7.09|7.19| |41|80|39|6.06|6.42|6.62|6.85|6.99|7.08| |46|85|39|6.06|6.42|6.62|6.85|6.99|7.08| |40|80|40|5.91|6.30|6.52|6.76|6.89|6.98| |45|85|40|5.91|6.30|6.52|6.76|6.89|6.98| |44|85|41|5.75|6.17|6.403|6.66|6.79|6.89| |43|85|42|5.57|6.03|6.28|6.55|6.70|6.79| |42|85|43|5.37|5.88|6.16|6.44|6.59|6.69| |41|85|44|5.15|5.71|6.01|6.33|6.49|6.59| |40|85|45|4.91|5.53|5.86|6.20|6.37|6.48| |Condenser DT2|Condenser DT2|Condenser DT2|14.04|11.23|9.36|7.02|5.62|4.68| |1. LIFT = Entering Condenser Water Temperature (°F) – Leaving Chilled Water Temperature (°F)
2.

CMC § 503.4 Medium relevance — show source text

See reference document for detailed information. 3 Et = thermal efficiency. See reference document for detailed information. 4 Maximum capacity—minimum and maximum ratings as provided for and allowed by the unit’s controls. 5 Includes oil-fired (residual). 6 Boilers shall not be equipped with a constant burning pilot light. 7 A boiler not equipped with a tankless domestic water-heating coil shall be equipped with an automatic means for adjusting the temperature of the water such that an incremental change in inferred heat load produces a corresponding incremental change in the temperature of the water supplied. 8 For new construction, refer to Section E 503.4 for additional system compliance requirements. 9 See Informative Appendix F, Table F-4 of ASHRAE 90.1, for U.S. minimum efficiencies for residential products covered by USDOE requirements for U.S. applications.

458 2025 CALIFORNIA MECHANICAL CODE

APPENDIX E

TABLE E 503.7.1(7) PERFORMANCE REQUIREMENTS FOR HEAT REJECTION EQUIPMENT—MINIMUM EFFICIENCY REQUIREMENTS

[ASHRAE 90.1: TABLE 6.8.1-7]

EQUIPMENT TYPE	TOTAL SYSTEM HEAT- REJECTION CAPACITY AT RATED CONDITIONS	SUBCATEGORY OR RATING CONDITION8	PERFORMANCE REQUIRED1,2,3,6,7	TEST PROCEDURE4,5
Propeller or axial fan open- circuit cooling towers	All	95°F entering water 85°F leaving water 75°F entering wb	≥40.2 gpm/hp	CTI ATC-105 and CTI STD-201 RS
Centrifugal fan open-circuit cooling towers	All	95°F entering water 85°F leaving water 75°F entering wb	≥20.0 gpm/hp	CTI ATC-105 and CTI STD-201 RS
Propeller or axial fan closed- circuit cooling towers	All	102°F entering water 90°F leaving water 75°F entering wb	≥16.1 gpm/hp	CTI ATC-105S and CTI STD-201 RS
Centrifugal closed- circuit cooling towers	All	102°F entering water 90°F leaving water 75°F entering wb	≥7.0 gpm/hp	CTI ATC-105S and CTI STD-201 RS
Propeller or axial fan dry coolers (air-cooled fluid cool- ers)	All	115°F entering water 105°F leaving water 95°F entering wb	≥4.5 gpm/hp	CTI ATC-105DS
Propeller or axial fan evapo- rative condensers	All	R-448A test fluid 165°F entering gas temperature 105°F condensing temperature 75°F entering wb	≥160 000 Btu/h·hp	CTI ATC-106
Propeller or axial fan evapo- rative condensers	All	Ammonia test fluid 140°F entering gas temperature 96.

CMC § 6.10 Medium relevance — show source text
84|6.10|6.30|6.61|6.84|7.00| |45|75|30|5.75|6.00|6.19|6.47|6.68|6.83| |44|75|31|5.67|5.91|6.08|6.34|6.53|6.67| |43|75|32|5.59|5.82|5.99|6.23|6.39|6.52| |42|75|33|5.51|5.74|5.90|6.12|6.27|6.39| |41|75|34|5.43|5.66|5.81|6.02|6.16|6.26| |46|80|34|5.43|5.66|5.81|6.02|6.16|6.26| |40|75|35|5.35|5.58|5.73|5.93|6.06|6.15| |45|80|35|5.35|5.58|5.73|5.93|6.06|6.15| |44|80|36|5.26|5.50|5.65|5.84|5.96|6.05| |43|80|37|5.16|5.42|5.57|5.76|5.87|5.96| |42|80|38|5.06|5.33|5.49|5.67|5.79|5.87| |41|80|39|4.95|5.24|5.41|5.60|5.71|5.78| |46|85|39|4.95|5.24|5.41|5.60|5.71|5.78| |40|80|40|4.83|5.14|5.32|5.52|5.63|5.70| |45|85|40|4.83|5.14|5.32|5.52|5.63|5.70| |44|85|41|4.69|5.04|5.253|5.43|5.55|5.62| |43|85|42|4.55|4.93|5.13|5.35|5.47|5.54| |42|85|43|4.38|4.80|5.03|5.26|5.38|5.46| |41|85|44|4.21|4.67|4.91|5.17|5.30|5.38| |40|85|45|4.01|4.52|4.79|5.06|5.20|5.29| |Condenser DT2|Condenser DT2|Condenser DT2|14.04|11.23|9.36|7.02|5.62|4.68| |1. LIFT = Entering Condenser Water Temperature (°F) – Leaving Chilled Water Temperature (°F)
2.

CMC § 90.1 Medium relevance — show source text

[ASHRAE 90.1: TABLE 6.4.3.4.3]

Col1	OUTDOOR AIR INTAKE (CFM/ft2)	Col3	EXHAUST/RELIEF (CFM/ft2)	Col5
CLIMATE ZONE	NONMOTORIZED1	MOTORIZED	NONMOTORIZED3	MOTORIZED
0, 1, 2	0, 1, 2	0, 1, 2	0, 1, 2	0, 1, 2
Any height	20	4	20	4
3	3	3	3	3
Any height	20	10	20	10
4, 5B, 5C	4, 5B, 5C	4, 5B, 5C	4, 5B, 5C	4, 5B, 5C
Fewer than three stories	204	10	20	10
Three or more stories	204	10	204	10
5A, 6, 7, 8	5A, 6, 7, 8	5A, 6, 7, 8	5A, 6, 7, 8	5A, 6, 7, 8
Fewer than three stories	204	4	20	4
Three or more stories	204	4	204	4

For SI units: 1 square foot = 0.0929 m [2], 1 cubic foot per minute = 0.00047 m [3] /s, 1 cubic foot per minute = 0.4719 L/s, 1 cubic foot per minute per square foot = 5.08 [(L/s)/m [2] ], 1 inch water gauge = 0.249 kPa

Notes:

1 When tested in accordance with AMCA 500D.

2 Dampers smaller than 12 inches (305 mm) in height, width, or diameter need not be tested but shall be of the same design and construction as the smallest tested damper meeting the listed leakage rate requirement.

3 Nonmotorized dampers smaller than 24 inches (610 mm) in height, width, or diameter shall be permitted to have a leakage rate of 40 CFM/ft 2 [0.203 (m 3 /s)/m 2 ].

4 Where permitted by Section E 503.4.6.4.1, exception 2.

2025 CALIFORNIA MECHANICAL CODE 425

APPENDIX E

(2) Systems serving zones where humidity levels are required to be maintained with precision of not more than ±5 percent relative humidity to comply with applicable codes or accreditation standards or as approved by the Authority Having Jurisdiction.

[ASHRAE 90.1:6.4.3.6.2]

CMC § 1305.2.3.3 Medium relevance — show source text
2, 1305.2.3.3, 1305.2.4.1, 1305.2.5, 1305.2.5.1, 1305.2.6, 1305.2.7.1, 1305.2.8, 1305.2.9, 1305.2.9.1, 1305.2.10, 1305.2.10.1, 1305.2.11, 1305.2.11.1, 1305.2.12.1, 1305.2.13, Table 1305.2.15, 1305.2.15.1, 1305.2.16.1, 1305.2.17, 1305.2.17.1, 1305.2.18, 1305.2.18.1, 1305.2.19, Table 1305.2.19, 1305.2.20, 1305.2.20.1, 1307.1.1, 1401.2, 1402.1, 1402.2, 1402.2.1, 1402.3, 1402.4, 1402.5, 1402.6, 1501.5, 1504.1.1, 1504.1.4.1, 1504.1.7, 1509.1, 1509.3, 1510.1

CEC — 25 : California Energy Code

302.2, 702.7, 708.1, 809.1, 907.1, 1104.1

CFC—25: California Fire Code

101.2.2, 101.4.2, 301.3.1, 302.2, 307.1, 308.1, 802.2.1, 802.2.3, 803.2.3, 803.4.1.1, 803.4.1.2, 803.4.1.3, 803.4.1.4, 803.4.1.5, 803.4.1.6, Table 804.5.1.1(1), 904.1.5, 1011.6.1.1, 1303.1.2, 1305.2.8.1, 1305.2.14, 1305.2.14.1, 1401.2, 1501.1, 1501.5, 1502.1, 1502.1.1, 1502.2, 1502.3, 1504.1, 1507.1, 1507.2

CMC—25: California Mechanical Code

302.2, 702.7, 807.1, 902.1.1, 1008.1, 1305.2.7.1, 1305.2.8, 1305.2.8.1

CPC—25: California Plumbing Code

302.2, 408.1, 702.7, 1009.1, 1009.2, 1009.3, 1009.5, 1302.1.6, 1503.1
CMC § 1.11. Medium relevance — show source text
Wall Assembly_|||X||||||||||||||||||||| |Exterior Wall Covering|||X||||||||||||||||||||| |Fire Code Official|||X||||||||||||||||||||| |Fire Hazard Severity Zones|||X||||||||||||||||||||| |Fire Protection Plan|||X||||||||||||||||||||| |Fire-Smart Vegetation|||X||||||||||||||||||||| |Flame Spread Index|||X||||||||||||||||||||| |Fuel|||X||||||||||||||||||||| |Fuel Modification|||X||||||||||||||||||||| |Local Responsibility Area (LRA)|||X||||||||||||||||||||| |Rafter Tail|||X||||||||||||||||||||| |Roof Eave|||X||||||||||||||||||||| |Roof Eave Soffit|||X||||||||||||||||||||| |State Responsibility Area (SRA)|||X||||||||||||||||||||| |Structure|||X||||||||||||||||||||| |Wildfire|||X||||||||||||||||||||| |Wildfire Exposure|||X||||||||||||||||||||| |Wildland-Urban Interface Area|||X|||||||||||||||||||||
- The California Code of Regulations (CCR), Title 19, Division 1 provisions that are found in the California Wildland-Urban Interface Code are a reprint from the current CCR, Title 19, Division 1 text for the code user’s convenience only. The scope, applicability and appeals procedures of CCR, Title 19, Division I remain the same. The state agency does not adopt sections identified by 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.
The California Code of Regulations (CCR), Title 14, Division 1.5 provisions that are found in the California Wildland-Urban Interface Code are not listed in the Matrix Adoption Tables as they are not within the State Fire Marshal’s authority to adopt. These provisions are a reprint from the current CCR, Title 14, Division 1.5 text for the code user’s convenience only and are identified in the body of the code by square brackets containing references to applicable Title 14 sections.

2025 CALIFORNIA WILDLAND-URBAN INTERFACE CODE 2-1

on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

2-2 2025 CALIFORNIA WILDLAND-URBAN INTERFACE CODE

on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

2 DEFINITIONS

User notes:

About this chapter: Codes, by their very nature, are technical documents. Every word, term and punctuation mark can add to or change the meaning of a technical requirement. It is necessary to maintain a consensus on the specific meaning of each term contained in the code. Chapter 2 performs this function by stating clearly what specific terms mean for the purpose of the code.

SECTION 201—GENERAL

201.1 Scope. Unless otherwise expressly stated, the following words and terms shall, for the purposes of this code, have the meanings shown in this chapter.

201.2 Interchangeability. Words stated in the present tense include the future; words stated in the masculine gender include the feminine and neuter; and the singular number includes the plural and the plural the singular.
CMC § 2-3 Medium relevance — show source text
VACUUM||||X|||||||||||||||||||| |REPAIR||||X|||||||||||||||||||| |REROOFING||||X|||||||||||||||||||| |RESIDENTIAL CARE FACILITY FOR THE
CHRONICALLY ILL (RCF/CI)|||X||||||||||||||||||||| |RESIDENTIAL CARE FACILITY FOR THE
ELDERLY (RCFE)|||X||||||||||||||||||||| |RESIDENTIAL FACILITY (RF)|||X||||||||||||||||||||| |RESTRAINT|||X||||||||||||||||||||| |ROOF ASSEMBLY||||X|||||||||||||||||||| |ROOF RECOVER||||X|||||||||||||||||||| |ROOF REPAIR||||X|||||||||||||||||||| |ROOF REPLACEMENT||||X|||||||||||||||||||| |SKYLIGHTS AND SLOPED GLAZING||||X|||||||||||||||||||| |SLEEPING UNIT||||X|||||||||||||||||||| |STATE-OWNED/LEASED BUILDING|||X||||||||||||||||||||| |SUBSTANTIAL IMPROVEMENT||||X|||||||||||||||||||| |SUNROOM||||X|||||||||||||||||||| |TERMINALLY ILL|||X||||||||||||||||||||| |TESTING AGENCY||||X|||||||||||||||||||| |THIRD-PARTY CERTIFICATION
AGENCY||||X|||||||||||||||||||| |THIRD-PARTY CERTIFIED||||X|||||||||||||||||||| |TODDLER|||X||||||||||||||||||||| |VENT||||X|||||||||||||||||||| |VENT CONNECTOR||||X|||||||||||||||||||| |VENT SYSTEM||||X|||||||||||||||||||| |VENTILATION||||X|||||||||||||||||||| |WATER HEATER||||X|||||||||||||||||||| |WHOLE-HOUSE MECHANICAL
VENTILATION SYSTEM||||X|||||||||||||||||||| |WILDLAND-URBAN INTERFACE (WUI)|||X|||||||||||||||||||||

The state agency does not adopt sections identified with the following symbol: †

2025 CALIFORNIA RESIDENTIAL CODE 2-3

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2-4 2025 CALIFORNIA RESIDENTIAL CODE

on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

Part II—Definitions

2 DEFINITIONS

User notes:

About this chapter: Codes, by their very nature, are technical documents. Every word, term and punctuation mark can add to or change the meaning of a technical requirement. It is necessary to maintain a consensus on the specific meaning of each term contained in the code. Chapter 2 performs this function by stating clearly what specific terms mean for the purpose of the code.

ICC code development note: Code change proposals to definitions in this chapter preceded by a bracketed letter are considered by the IRC—Building Code Development Committee [RB], the IRC—Mechanical/Plumbing Code Development Committee [MP] or the IECC—Residential Code Development Committee [RE] during the Group B (2025) Code Development Cycle.

SECTION R201—GENERAL

R201.1 Scope. Unless otherwise expressly stated, the following words and terms shall, for the purposes of this code, have the meanings indicated in this chapter.
CMC § 201.1 Medium relevance — show source text
SECTION 201—GENERAL

201.1 Scope. Unless otherwise expressly stated, the following words and terms shall, for the purposes of this code, have the meanings shown in this chapter.

201.2 Interchangeability. Words used in the present tense include the future; words stated in the masculine gender include the feminine and neuter; the singular number includes the plural and the plural, the singular.

201.3 Terms defined in other codes. Where terms are not defined in this code and are defined in the other California Codes, such terms shall have the meanings ascribed to them in those codes. [OSHPD 1, 1R, 2, 4 & 5] For terms not defined in this chapter, refer to Chapters 6 and 7 of the California Administrative Code, and Chapter 2 of the California Building Code. [DSA-SS & DSA-SS/CC] Definitions of terms given in Section 4-207 or 4-314 of the California Administrative Code govern over those in Section 202.

201.4 Terms not defined. Where terms are not defined through the methods authorized by this chapter, such terms shall have ordinarily accepted meanings such as the context implies.

SECTION 202—GENERAL DEFINITIONS

ACCESSORY DWELLING UNIT. [HCD 1 & HCD 2] An attached or detached residential dwelling unit that provides complete independent living facilities for one or more persons and is located on a lot with a proposed or existing primary residence. Accessory dwelling units shall include permanent provisions for living, sleeping, eating, cooking and sanitation on the same parcel as the single-family or multi- family dwelling is or will be situated. (See Government Code Section 65852.2.)

[A] ADDITION. An extension or increase in floor area, number of stories, or height of a building or structure.

[A] ALTERATION. Any construction or renovation to an existing structure other than a repair or addition.

[BG] AMBULATORY CARE FACILITY. Buildings or portions thereof used to provide medical, surgical, psychiatric, nursing or similar care on a less than 24-hour basis to persons who are rendered incapable of self-preservation by the services provided or staff has accepted responsibility for care recipients already incapable.

[A] APPROVED. Acceptable to the code official.

Exception: [HCD 1 & HCD 2] “Approved” means meeting the approval of the Enforcing Agency, except as otherwise provided by law, when used in connection with any system, material, type of construction, fixture or appliance as the result of investigations and tests conducted by the agency, or by reason of accepted principles or tests by national authorities, or technical, health, or scientific organi- zations or agencies.

Notes :

1. See Health and Safety Code Section 17920 for “Approved” as applied to residential construction and buildings or struc- tures accessory thereto as referenced in Section 1.8.2. 2. See Health and Safety Code Section 17921.1 for “Approved” as applied to the use of hotplates in residential construction as referenced in Section 1.8.2.

3. See Health and Safety Code Section 19966 for “Approved” as applied to Factory-Built Housing as referenced in Section 1.8.3.2.5.
CMC § 2-3 Medium relevance — show source text
SYSTEM||||X|||||||||||||||||||| |VENTILATION||||X|||||||||||||||||||| |WATER HEATER||||X|||||||||||||||||||| |WHOLE-HOUSE MECHANICAL
VENTILATION SYSTEM||||X|||||||||||||||||||| |WILDLAND-URBAN INTERFACE (WUI)|||X|||||||||||||||||||||

The state agency does not adopt sections identified with the following symbol: †

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Part II—Definitions

2 DEFINITIONS

User notes:

About this chapter: Codes, by their very nature, are technical documents. Every word, term and punctuation mark can add to or change the meaning of a technical requirement. It is necessary to maintain a consensus on the specific meaning of each term contained in the code. Chapter 2 performs this function by stating clearly what specific terms mean for the purpose of the code.

ICC code development note: Code change proposals to definitions in this chapter preceded by a bracketed letter are considered by the IRC—Building Code Development Committee [RB], the IRC—Mechanical/Plumbing Code Development Committee [MP] or the IECC—Residential Code Development Committee [RE] during the Group B (2025) Code Development Cycle.

SECTION R201—GENERAL

R201.1 Scope. Unless otherwise expressly stated, the following words and terms shall, for the purposes of this code, have the meanings indicated in this chapter.

R201.2 Interchangeability. Words used in the present tense include the future; words in the masculine gender include the feminine and neuter; the singular number includes the plural and the plural, the singular.

R201.3 Terms defined in other codes. Where terms are not defined in this code such terms shall have the meanings ascribed in the California Building Standards Code, Title 24, California Code of Regulations.

R201.4 Terms not defined. Where terms are not defined through the methods authorized by this section, such terms shall have ordinarily accepted meanings such as the context implies.

For applications listed in Section 1.11 regulated by the Office of the State Fire Marshal, where terms are not defined through the meth- ods authorized by this section, such terms shall have ordinarily accepted meanings such as the context implies. Webster’s Third New International Dictionary of the English Language, Unabridged, shall be considered as providing ordinarily accepted meanings.

SECTION R202—DEFINITIONS

[RB] ACCESS (TO). That which enables a device, an appliance or equipment to be reached by ready access or by a means that first requires the removal or movement of a panel, door or similar obstruction.

ACCESSORY DWELLING UNIT. [HCD 1 & HCD 2] An attached or detached residential dwelling unit that provides complete independent living facilities for one or more persons and is located on a lot with a proposed or existing primary residence. Accessory dwelling units shall include permanent provisions for living, sleeping, eating, cooking and sanitation on the same parcel as the single-family or multifamily dwelling is or will be situated. (See Government Code Section 65852.2)
CMC § 2-4 Medium relevance — show source text
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2 DEFINITIONS

User notes:

About this chapter: Codes, by their very nature, are technical documents. Every word, term and punctuation mark can add to or change the meaning of a technical requirement. It is necessary to maintain a consensus on the specific meaning of each term contained in the code. Chapter 2 performs this function by stating clearly what specific terms mean for the purpose of the code. General definitions are located in Section 202 and occupancy classification definitions are located in Section 203.

SECTION 201—GENERAL

201.1 Scope. Unless otherwise expressly stated, the following words and terms shall, for the purposes of this code, have the meanings shown in this chapter.

201.2 Interchangeability. Words used in the present tense include the future; words stated in the masculine gender include the feminine and neuter; the singular number includes the plural and the plural, the singular.

201.3 Terms defined in other codes. Where terms are not defined in this code and are defined in the California Building Code, Cali- fornia Mechanical Code or California Plumbing Code, such terms shall have the meanings ascribed to them as in those codes.

201.4 Terms not defined. Where terms are not defined through the methods authorized by this section, such terms shall have ordinarily accepted meanings such as the context implies. Merriam Webster’s Collegiate Dictionary, 11th Edition, shall be considered as providing ordinarily accepted meanings.

SECTION 202—GENERAL DEFINITIONS

[BG] 24-HOUR BASIS. The actual time that a person is an occupant within a facility for the purpose of receiving care. It shall not include a facility that is open for 24 hours and is capable of providing care to someone visiting the facility during any segment of the 24 hours.

3D PRINTER. A machine used in the additive manufacturing process for fabricating objects through the deposition of a material using a print head, nozzle or other printer technology.

[M] ACCESS (TO). That which enables a device, appliance or equipment to be reached by ready access or by a means that first requires the removal or movement of a panel or similar obstruction [see also “Ready access (to)”].

[BE] ACCESSIBLE MEANS OF EGRESS. A continuous and unobstructed way of egress travel from any accessible point in a building or facility to a public way.

[BE] ACCESSIBLE ROUTE. A continuous, unobstructed path that complies with Chapter 11 of the California Building Code .

ACTIVE RF EMITTING DEVICE. Any type of circuit component that requires an AC or DC power source with the ability to electrically control electron flow and/or amplification of RF signal, including but not limited to signal boosters, repeaters, bidirectional amplifiers and fiber-distributed antenna systems.

ADDITIVE MANUFACTURING. A process of joining materials to make objects from 3D model data, usually layer upon layer, sometimes referred to as 3D printing. This code recognizes two types of additive manufacturing:

Industrial additive manufacturing. 3D printing operations that typically utilize combustible powders or metals, an inert gas supply, a combustible dust collection system, or that create a hazardous (classified) location area or zone outside the equipment.
CMC § 1220.4.2 Medium relevance — show source text
8|1220.4.2 – 1220.4.6| |1221.7|1221.6| |1308.2 – 1308.4.1|1308.3 – 1308.5.1| |Table 1308.3.1|Table 1308.4.1| |1308.4.2|1308.5.2| |1308.4.2.2 – 1308.6.4|1308.5.2.1 – 1308.7.3| |Table 1308.4.6.2|Table 1308.5.6.2| |1308.6.5 – 1308.13.1|1308.7.7 – 1308.14.1| |1312.1.2 – 1312.1.3|1312.1.1 – 1312.1.2| |Chapter 17|Appendix F| |Chapter 18|Chapter 17| |D 103.2|D 103.1| |E 503.5.6.7|E 503.5.6.6| |E 503.5.7.2 – E 503.5.7.6|E 503.5.7.1 – E 503.5.7.5| |Table E 503.5.7.2|Table E 503.5.7.1| |Table E 503.5.7.6|Table E 503.5.7.5| |Table E 503.5.10.1.2(1)|Table E 503.5.10(1)| |Table E 503.5.10.1.2(2)|Table E 503.5.10(2)| |E 503.5.10.1.2|E 503.5.10| |E 503.5.10.2 – E 503.5.10.2.2|E 503.5.10.1 – E 503.5.10.1.2| |E 503.5.12.1|E 503.5.12| |E 503.5.12.2|E 503.5.12.1| |E 503.6.5.4|E 503.6.5.4.1|

xxii 2025 CALIFORNIA MECHANICAL CODE

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Uniform Mechanical Code – 2024 Edition:

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Uniform Mechanical Code Illustrated Training Manual:
CMC § 100.0 Medium relevance — show source text
Exception 1 to Section 100.0(f): If one occupancy constitutes at least 80 percent of the conditioned floor area of the building, the entire building envelope, HVAC and water heating may be designed to comply with the provisions of Part 6 applicable to that occupancy, provided that the applicable lighting requirements in Sections 140.6 through 140.8, 150.0(k), or 160.5 and 170.2(e) are met for each occupancy and space, and mandatory measures in Sections 110.0 through 130.5, 150.0, and 160.0 through 160.9 are met for each occupancy and space.

Exception 2 to Section 100.0(f): If one occupancy constitutes at least 90 percent of the combined conditioned plus unconditioned floor area of the building, the entire building indoor lighting may be designed to comply with only the lighting provisions of Part 6 applicable to that occupancy.

(g) Administrative requirements. Administrative requirements relating to permit requirements, enforcement by the Commission, locally adopted energy standards, interpretations, claims of exemption, approved calculation methods, rights of appeal, and certification and labeling requirements of fenestration products and roofing products are specified in California Code of Regulations, Title 24, Part 1, Sections 10-101 to 10-114.

(h) Certification requirements for manufactured equipment, products and devices. Part 6 limits the installation of manufactured equipment, products and devices to those that have been certified as specified by Sections 110.0 and 110.1. Requirements for manufactured equipment, products, and devices, when not specified in Title 24 Part 6, are specified in California Code of Regulations, Title 20, Sections 1601–1609.

Note: Authority: Sections 25213, 25218, 25218.5, 25402 and 25402.1, Public Resources Code . Reference: Sections 25007, 25008, 25218.5, 25310, 25402, 25402.1, 25402.4, 25402.5, 25402.8, and 25943, Public Resources Code .

SECTION 100.1 — DEFINITIONS AND RULES OF CONSTRUCTION

(a) Rules of Construction.
1. Where the context requires, the singular includes the plural and the plural includes the singular.
2. The use of “and” in a conjunctive provision means that all elements in the provision must be complied with or must exist to make the provision applicable. Where compliance with one or more elements suffices, or where existence of one or more elements makes the provision applicable, “or” (rather than “and/or”) is used.
3. “Shall” is mandatory and “may” is permissive.
(b) Definitions. Terms, phrases, words and their derivatives in Part 6 shall be defined as specified in Section 100.1. Terms, phrases, words and their derivatives not found in Section 100.1 shall be defined as specified in the “Definitions” chapters of Title 24, Parts 1 through 5 of the California Code of Regulations. Where terms, phrases, words and their derivatives are not defined in any of the references above, they shall be defined as specified in Webster’s Third New International Dictionary of the English Language, Unabridged (1961 edition, through the 2002 addenda), unless the context requires otherwise.

Frequently asked questions

When should I stop searching Chapter 2 and look elsewhere?

Stop after you confirm Chapter 2 has no entry for the specific term. At that point the CMC directs you to other California codes and referenced documents under § 201.3; if still undefined, use ordinary meaning under § 201.4 .

If a referenced standard (e.g., ASHRAE) defines a term, does that override CMC Chapter 2?

Only if the CMC text or the specific provision tells you to use the referenced standard’s definition. Otherwise use Chapter 2 first, then other California codes per § 201.3, then referenced standards if the code directs you to them .

Where do I find jurisdictional exceptions that change definitions?

Check the CMC front matter and the adoption/matrix tables for that jurisdiction or state agency; those notes show sections adopted, amended, or not adopted and can change which definitions apply .

If Chapter 2 defines a term differently than the Building Code, which do I use?

For the Mechanical Code context use the Mechanical Code (Chapter 2) definition unless the specific mechanical provision says otherwise. If the mechanical text says “as defined in the Building Code,” follow that direction — this hierarchy is reflected in § 201.1 and § 201.3 .

Does the CMC point to a specific dictionary for ordinary meanings?

The CMC directs the use of “ordinarily accepted meanings” (§ 201.4). The retrieved CMC text does not name a single required dictionary; some other California codes do cite a specific dictionary. If a particular jurisdiction or adopting agency prescribes a dictionary, that local instruction controls .

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