CMC · California Mechanical Code
How are gender, tense, singular/plural and cross-references handled in definitions?
The Mechanical Code says: read definitions flexibly — present tense covers the future, masculine wording includes feminine/neuter, and singular covers plural (and vice versa) — and if the CMC doesn’t define a term, use the definition from the other California code that does.
Last reviewed: July 6, 2026
What the code requires — 2-4 sentences
The California Mechanical Code treats wording in definitions as interchangeable for tense, gender and number: words used 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 — this is set out in § 201.2 of the code. For terms not defined in the Mechanical Code, the code requires using the meanings assigned to those terms in the other listed California codes (for example, the Building, Plumbing, Fire, Electrical, Energy Codes) per § 201.3. These two rules are the controlling rules-of-construction for Chapter 2 definitions in the CMC.
Read plainly: use normal English flexibility — tense, gender and number in definitions are not meant to limit meaning, and if the CMC is silent on a term, look to the other California codes listed in § 201.3.
Requirements in detail
1) Tense
- Rule: Present tense includes the future.
- Effect: A definition or requirement written in present tense applies equally to future actions or future-required installations unless a section expressly limits time.
- Code Reference: § 201.2.
2) Gender
- Rule: Masculine includes the feminine and neuter.
- Effect: Pronouns or gendered terms using masculine form are intended to cover all genders; do not treat masculine wording as limiting.
- Code Reference: § 201.2.
3) Number (singular / plural)
- Rule: Singular includes plural and plural includes singular.
- Effect: A defined term written in singular form applies when multiple items are involved, and a plural term may be read to include a single item depending on context. This prevents overly literal drafting from changing applicability.
- Code Reference: § 201.2.
4) Cross-references / terms defined elsewhere
- Rule: If a term is not defined in the CMC but is defined in one of the listed California codes, the meaning given in those other codes controls for CMC use.
- Effect: Always check the California Building Code, California Plumbing Code, California Fire Code, California Electrical Code, California Energy Code and other listed sources when a term is not defined in the CMC. Use the external code’s definition as the operative meaning in CMC provisions unless the CMC expressly states otherwise.
- Code Reference: § 201.3.
Markdown decision table (quick reference):
| Decision dimension | Value / reading rule | Practical effect | Code Reference |
|---|---|---|---|
| Tense | Present = Present + Future | A present-tense definition covers future installations/conditions unless limited | § 201.2 |
| Gender | Masculine = Masculine + Feminine + Neuter | Avoids gender-based limitation of meaning | § 201.2 |
| Number | Singular ⇄ Plural | Singular definitions apply to multiple items and vice versa where context permits | § 201.2 |
| Cross-code terms | Use definitions from listed California codes when CMC silent | Look up the listed code to find the controlling definition | § 201.3 |
How to apply the rules in practice
- Always read a defined term in the light of § 201.2 first to determine whether you should broaden tense/gender/number.
- If the CMC does not define the term, consult the other California codes named in § 201.3 and adopt that external definition for use in the CMC.
Exceptions & special cases
- The CMC text in § 201.2 and § 201.3 is a default rule of construction; a specific CMC provision that expressly states a different temporal, gender or numeric meaning will control over this general rule. The code gives these interchangeability rules as presumptive, not absolute, guidance.
- Where a term is defined differently in multiple listed California codes, the CMC does not itself tell you which external code to prefer — you must use context (the referenced discipline, cited section, or code cross-reference) to select the appropriate external definition. § 201.3 tells you to use the other code’s meaning when the term is defined there, but it does not resolve conflicts among external codes; you must rely on the CMC text and context to determine which external definition applies.
- If a term is neither defined in the CMC nor in the listed external California codes, the code directs you to ordinary accepted meanings (this is handled by the general definitions chapter; see related provisions). If you need the canonical dictionary meaning or other authority for an undefined term, the CMC framework contemplates that step (see the definitions/terms-not-defined guidance). The controlling sections for interchangeability and cross-code referencing remain § 201.2 and § 201.3.
Common mistakes
- Mistake: Treating masculine wording as limiting the rule to men or male-referenced objects. Correction: read the masculine form to include feminine and neuter under § 201.2.
- Mistake: Assuming a singular-defined term cannot apply to multiple devices or locations. Correction: read singular to include plural and vice versa per § 201.2.
- Mistake: Failing to check other listed California codes when a technical term is absent from the CMC. Correction: if the term is defined elsewhere, use that definition under § 201.3 before applying your own plain-English reading.
- Mistake: Overriding these rules with informal reading (e.g., assuming “present tense” means “only now”). Correction: the code explicitly extends present-tense wording to the future under § 201.2.
Worked example — concrete scenario applying the rule
Scenario: The CMC contains a definition that reads **“An appliance is a device that serves a single occupancy.” The installation requirements elsewhere state “Each appliance shall have an accessible shutoff.”
Application:
- Under § 201.2 the singular word “appliance” in the definition covers the plural — so the phrase “each appliance” applies to every appliance installed (1, 2, or 10). If a room contains 3 appliances, the requirement to provide an accessible shutoff for each appliance applies 3 times.
- If that same term “appliance” is not defined in the CMC but a matching technical definition exists in the California Plumbing Code, § 201.3 requires you to use the Plumbing Code’s definition for the CMC’s purposes — for example, how “serves a single occupancy” is interpreted or whether a combined unit counts as one appliance or multiple.
Numeric illustration:
- Requirement: “Each appliance must be within 6 feet of a shutoff.”
- If you install 4 appliances, you must provide 4 shutoffs (one for each) located within 6 feet of each appliance. The singular/plural rules in § 201.2 prevent reading “appliance” as applying to only a single device.
Related provisions
- § 201.1 — Scope (general application of Chapter 2 definitions).
- § 201.4 — Terms not defined (guidance on ordinarily accepted meanings when not defined in this or listed codes).
- Chapter 2 — Definitions (collection of defined terms used throughout the CMC).
Code references
Grounded in the retrieved California Mechanical Code — click a citation to read the verbatim passage:
CMC § 201.1 Medium relevance — show source text
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.
ACCESS AISLE. [DSA-AC] An accessible space adjacent to or between vehicle spaces that provides clearances in compliance with this code.
ACCESSIBILITY. [DSA-AC & HCD 1-AC] The combination of various elements in a building, facility, site or area, or portion thereof which allows access, circulation and the full use of the building and facilities by persons with disabilities in compliance with this code.
ACCESSIBILITY FUNCTION BUTTON. [DSA-AC] A button on an elevator hall call console in a destination-oriented elevator system that when pressed will activate a series of visual and verbal prompts and announcements providing instruction regarding hall call console operation and direction to an assigned elevator.
ACCESSIBLE. [DSA-AC & HCD 1-AC] A site, building, facility, or portion thereof that is approachable and usable by persons with disabili- ties in compliance with this code.
ACCESSIBLE ELEMENT. [DSA-AC] An element specified by the regulations adopted by the Division of the State Architect—Access Compliance.
[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.
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 § 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.
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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.
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 § 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-
CGSFM HCD Col6 Col7 DSA Col9 OSHPD Col11 Col12 Col13 Col14 Col15 BSCC DPH AGR DWR CEC CA SL SLC Adopting agency BSC BSC-
CGSFM 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 belowChapter/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: †.
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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 § 1.11 Medium relevance — show source text
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)
[RB] ACCESSORY STRUCTURE. A structure that is accessory to and incidental to that of the dwelling(s) or townhouse(s) and that is located on the same lot.
[RB] ADDITION. An extension or increase in floor area, number of stories or height of a building or structure.
[RB] ADHERED STONE OR MASONRY VENEER. Stone or masonry veneer secured and supported through the adhesion of an approved bonding material applied to an approved backing.
AGED HOME OR INSTITUTION. A facility used for the housing of persons 65 years of age or older in need of care and supervision. (See defi- nition of “care and supervision.”)
[MP] AIR, OUTDOOR. Ambient air that enters a building through a ventilation system, through intentional openings for natural ventilation or by infiltration.
[MP] AIR, TRANSFER. Air moved from one indoor space to another.
[MP] AIR ADMITTANCE VALVE. A one-way valve designed to allow air into the plumbing drainage system where a negative pressure develops in the piping. This device shall close by gravity and seal the terminal under conditions of zero differential pressure (no flow conditions) and under positive internal pressure.
[MP] AIR BREAK (DRAINAGE SYSTEM). An arrangement where a discharge pipe from a fixture, appliance or device drains indirectly into a receptor below the flood-level rim of the receptor and above the trap seal.
[MP] AIR CIRCULATION, FORCED. A means of providing space conditioning utilizing movement of air through ducts or plenums by mechanical means.
[MP] AIR GAP, DRAINAGE SYSTEM. The unobstructed vertical distance through free atmosphere between the outlet of a waste pipe and the flood-level rim of the fixture or receptor into which it is discharging.
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.
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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
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.
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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.
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 § 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.
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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.
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
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 § 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.
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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 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 § 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.
- Where the context requires, the singular includes the plural and the plural includes the singular.
- 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.
- “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.
CMC § 2-4 Medium relevance — show source text
2-4 2025 CALIFORNIA FIRE CODE
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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 § 2-1 Medium relevance — show source text
RESIDENTIAL
CODE|||||||||†||†||†|||||||||| |LOW-RISE
RESIDENTIAL BUILDING|||||||||†||†||†|||||||||| |PLANTS|||||||||†||†||†|||||||||| |RESIDENTIAL BUILDING|||||||||†||†||†|||||||||| |RESILIENT FLOORING|||||||||†||†||†||||||||||The state agency does not adopt sections identified by the following symbol: †.
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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
2 X 2 RULE. [BSC-CG] Visual markers are the most effective collision deterrents if spaced no more than 2 inches (5.1 cm) apart, a distance through which most birds cannot fly.
ACCESSORY DWELLING UNIT. [HCD] 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 singlefamily or multifamily dwelling is or will be situated. (See Government Code Section 65852.2.)
ACCESSORY OCCUPANCIES. [HCD] Occupancies that are ancillary to the main occupancy of residential building(s) or portions thereof. Accessory occupancies shall include, but are not limited to, Group U occupancies. (See Section 312 of the California Build- ing Code. )
ACCESSORY STRUCTURE. [HCD] A structure that is accessory to and incidental to that of the dwelling(s) and that is located on the same lot.
ADDITION. An extension or increase in floor area of an existing building or structure.
ADHESIVE MARKER. [BSC-CG] An individual marker(s) applied to the first surface of glass (surface 1) in a pattern or as a custom decal.
ADJUST. To regulate fluid flow rate and air patterns at the terminal equipment, such as to reduce fan speed or adjust a damper.
AGRIFIBER PRODUCTS. Agrifiber products include wheatboard, strawboard, panel substrates and door cores, not including furniture, fixtures and equipment (FF&E) not considered base building elements.
Frequently asked questions
What if a term is defined differently in two external California codes listed by § 201.3?
When the CMC is silent and two listed codes define a term differently, the CMC does not itself pick one — you must use context (which code the CMC references in that provision, the subject matter, or specific cross-references) to determine the applicable external definition. § 201.3 requires you to use definitions from the listed codes when the CMC lacks a definition.
Does § 201.2 change mandatory language like “shall” or permissive language like “may”?
No. § 201.2 governs interchangeability of tense, gender and number; it does not change the legal force of “shall” vs “may.” If you need the rule about mandatory vs permissive words, consult the specific sections that address rules of construction elsewhere in Title 24 or the particular code part. The CMC’s § 201.2 itself does not state rule-of-thumb about “shall/may.”
If the CMC defines a term in the singular, may a local jurisdiction adopt a local amendment that changes it to plural-only?
Local amendments can modify definitions per the normal local-adoption process, but you must follow state/local adoption rules. The CMC’s § 201.2 is a construction rule; if a local jurisdiction amends the text to create a different definition, that amendment governs locally according to the usual amendment procedures. Check local amendments and adoption notices.
Do I always need to look up external definitions cited in § 201.3?
Yes — when a term is not defined in the CMC and is defined in one of the listed California codes, § 201.3 instructs you to apply the external code’s definition for CMC purposes. That lookup avoids misinterpretation.
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