CRC · California Residential Code
When does the CRC defer to other codes for definitions?
If a word in the California Residential Code isn’t defined in CRC Chapter 2, the CRC tells you to use the definition found in the California Building Standards Code (Title 24) via § R201.3; if neither CRC nor Title 24 define the term, use its ordinarily accepted meaning per § R201.4.
Last reviewed: July 6, 2026
What the code requires — plain English (controlling §)
When a term is not defined in the California Residential Code, the CRC tells you to use the meaning assigned in the California Building Standards Code (Title 24). This rule is stated in § R201.3.
If the CRC itself has no definition for a word or phrase used in a residential requirement, look to Title 24 (the California Building Standards Code) for the definition called out by the CRC.
Requirements in detail
Core rule
- The CRC defines terms in Chapter 2; when a word or term is not defined there, the CRC defers to definitions contained in Title 24 (California Building Standards Code) — § R201.3.
How this fits with adjacent rules
- If the CRC does define the term, that CRC definition controls (see § R201.1: “Unless otherwise expressly stated...” — the CRC’s own definitions apply).
- If neither the CRC nor Title 24 supply a definition, the CRC directs application of an ordinarily accepted meaning as implied by context (see § R201.4).
Decision matrix (quick reference)
| Question / dimension | Outcome | Code Reference |
|---|---|---|
| Is the term defined in CRC Chapter 2? | Use the CRC definition (CRC controls). | § R201.1 |
| Not defined in CRC — is it defined anywhere in Title 24? | Use the Title 24 (California Building Standards Code) definition (CRC defers). | § R201.3 |
| Not in CRC or Title 24 — ordinary dictionary meaning? | Use ordinarily accepted meaning implied by context. | § R201.4 |
| Conflicting local amendment or specific code direction? | Apply the specific/local provision where adopted and applicable (check local adoptions/amendments). | See Chapter/administrative provisions in CRC and local adoption rules (see CRC front matter) |
Practical notes for code users
- "Title 24" is broad — it includes the California Building Code and other Parts adopted as the California Building Standards Code; the CRC’s instruction is to look to Title 24 definitions when the CRC is silent.
- The CRC’s deferral is automatic only when the CRC is silent. If the CRC supplies a definition, that definition is controlling even if Title 24 has a different wording.
Exceptions & special cases
- If a CRC provision “expressly states” a different definition or indicates use of another code, that express direction overrides the general deferral rule (compare § R201.1 with § R201.3).
- Some related California codes (for example, other Parts of Title 24 such as the California Building Code, California Fire Code, etc.) include their own R201.3‑style language for cross‑deferral. When a Title 24 Part provides a definition for the term, that Title 24 Part’s definition is the one the CRC points you to. (The CRC itself does not list every Part by name in § R201.3; it points generically to Title 24.)
- If a term is defined in a referenced standard (e.g., a standard adopted by Title 24) but that standard is not part of Title 24 definitions, check the specific adoption language and the Title 24 Part that references the standard to know whether that external definition is binding.
Common mistakes
- Assuming CRC defers to the model International codes (IRC/IBC) or to federal standards instead of to Title 24 — the CRC specifically refers to the California Building Standards Code (Title 24). Do not substitute a model‑code definition unless it is the definition actually adopted in Title 24. § R201.3.
- Using a Title 24 definition even when the CRC provides its own definition for the same term — the CRC definition controls when present. Check CRC Chapter 2 first.
- Treating the deferral as optional: the CRC’s direction is mandatory where the CRC is silent — you must look to Title 24 definitions per § R201.3.
Worked example — concrete scenario
Scenario: A plan reviewer is evaluating a new, two‑story, 2,400 ft² single‑family dwelling. The plan uses the term “mixed‑use space” in a life‑safety sentence, but the reviewer cannot find “mixed‑use space” in CRC Chapter 2.
Steps applying the rule:
- Check CRC Chapter 2 for a definition of “mixed‑use space.” If present, apply it. (Not found in this scenario.) § R201.1 / R202.
- Since CRC is silent, follow § R201.3: search Title 24 (the California Building Standards Code) for a definition. If a Title 24 part (for example the California Building Code) defines “mixed‑use space”, use that definition for the residential review. § R201.3
- If no Title 24 part defines it either, apply the ordinarily accepted meaning from context—per § R201.4—and document the interpretation. § R201.4
Outcome: The reviewer must locate any Title 24 definition (or lack thereof) before relying on a dictionary or industry usage.
Related provisions (CRC)
- § R201.1 — Scope and how CRC definitions are used.
- § R201.2 — Interchangeability (gender, number, tense).
- § R201.3 — Terms defined in other codes (controlling section).
- § R201.4 — Terms not defined: ordinarily accepted meanings.
- § R202 — The CRC’s definitions chapter (look here first for CRC definitions).
Code references
Grounded in the retrieved California Residential Code — click a citation to read the verbatim passage:
CRC § 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)
CRC § 2025 Medium relevance — show source text
It is important to understand that the IRC contains coverage for what is conventional and common in residential construction practice. While the IRC will provide all of the needed coverage for most residential construction, it might not address construction practices and systems that are atypical or rarely encountered in the industry. Therefore, the IRC contains several references to other codes either as an alternative to the provisions of the IRC or where the IRC lacks coverage for a particular type of structure, design, system, appliance or method of construction. In other words, the IRC is meant to be all inclusive for typical residential construction and it relies on other codes only where alternatives are desired or where the code lacks coverage for the uncommon aspect of residential construction. Of course, the IRC constantly evolves to address new technologies and construction practices that were once uncommon, but are now common.
The IRC is unique in that much of it, including Chapters 3 through 9 and Chapters 34 through 43, is presented in an ordered format that is consistent with the normal progression of construction, starting with the design phase and continuing through the final trimout phase. This is consistent with the “cookbook” philosophy of the IRC.
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Arrangement and Format of the 2025 CRC
The CRC is divided into nine main parts, specifically: Part I—Administrative, Part II—Definitions, Part III—Building Planning and Construction, Part IV—Energy Conservation, Part V—Mechanical, Part VI—Fuel Gas, Part VII—Plumbing, Part VIII—Electrical and Part IX—Referenced Standards. Parts IV through VIII of IRC are not adopted in California and replaced with references to appropriate parts of Title 24. The following provides a brief description of the content of each chapter and appendix of the CRC:
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 Building Planning.
Chapter 3 provides guidelines for a minimum level of structural integrity, life safety, fire safety and livability for inhabitants of dwelling units regulated by this code. Chapter 3 is a compilation of the code requirements specific to the building planning sector of the design and construction process. This chapter sets forth code requirements dealing with light, ventilation, sanitation, minimum room size, ceiling height and environmental comfort. Chapter 3 establishes life-safety provisions including limitations on glazing used in hazardous areas, specifications on stairways, use of guards at elevated surfaces, window and fall protection, and rules for means of egress. Snow, wind and seismic design live and dead loads and flood-resistant construction, as well as solar energy systems are addressed in this chapter.
Chapter 4 Foundations.
CRC § R301.1 Medium relevance — show source text
Coordination of the I-Codes
The coordination of technical provisions allows the I-Codes to be used as a complete set of complementary documents. Individual codes can also be used in subsets or as stand-alone documents. Some technical provisions that are relevant to more than one subject area are duplicated in multiple model codes.
INTRODUCTION TO THE INTERNATIONAL RESIDENTIAL CODE
The IRC establishes minimum requirements for one- and two-family dwellings and townhouses using prescriptive provisions. It is founded on broad-based principles that make possible the use of new materials and new building designs. This 2024 edition is fully compatible with all of the International Codes® (I-Codes®) published by the ICC.
The IRC was created to serve as a complete, comprehensive code regulating the construction of single-family houses, two-family houses (duplexes) and buildings consisting of three or more townhouse units. All buildings within the scope of the IRC are limited to three stories above grade plane. For example, a four-story single-family house would fall within the scope of the IBC, not the IRC. The benefits of devoting a separate code to residential construction include the fact that the user need not navigate through a multitude of code provisions that do not apply to residential construction in order to locate that which is applicable. A separate code also allows for residential and nonresidential code provisions to be distinct and tailored to the structures that fall within the appropriate code’s scopes.
The IRC contains coverage for all components of a house or townhouse, including structural components, fireplaces and chimneys, thermal insulation, mechanical systems, fuel gas systems, plumbing systems and electrical systems.
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The IRC is a prescriptive-oriented (specification) code with some examples of performance code language. It has been said that the IRC is the complete cookbook for residential construction. Section R301.1, for example, is written in performance language, but states that the prescriptive requirements of the code will achieve such performance.
It is important to understand that the IRC contains coverage for what is conventional and common in residential construction practice. While the IRC will provide all of the needed coverage for most residential construction, it might not address construction practices and systems that are atypical or rarely encountered in the industry. Therefore, the IRC contains several references to other codes either as an alternative to the provisions of the IRC or where the IRC lacks coverage for a particular type of structure, design, system, appliance or method of construction. In other words, the IRC is meant to be all inclusive for typical residential construction and it relies on other codes only where alternatives are desired or where the code lacks coverage for the uncommon aspect of residential construction. Of course, the IRC constantly evolves to address new technologies and construction practices that were once uncommon, but are now common.
The IRC is unique in that much of it, including Chapters 3 through 9 and Chapters 34 through 43, is presented in an ordered format that is consistent with the normal progression of construction, starting with the design phase and continuing through the final trimout phase. This is consistent with the “cookbook” philosophy of the IRC.
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Arrangement and Format of the 2025 CRC
CRC § 1.1.4 Medium relevance — show source text
1.1.4 Appendices. Provisions contained in the appendices of this code shall not apply unless specifically adopted by a state agency or adopted by a local enforcing agency in compliance with Health and Safety Code, Section 18901 et. seq. for Building Standards Law, Health and Safety Code, Section 17950 for State Housing Law and Health and Safety Code, Section 13869.7 for Fire Protection Districts. See Section 1.1.8 of this code.
1.1.5 Referenced codes. The codes, standards, and publications adopted and set forth in this code, including other codes, standards, and publications referred to herein are, by title and date of publication, hereby adopted as standard reference documents of this code. When this code does not specifically cover any subject related to building design and construction, recognized architectural or engineer- ing practices shall be employed. The National Fire Codes, standards, and the Fire Protection Handbook of the National Fire Protection Association are permitted to be used as authoritative guides in determining recognized fire prevention engineering practices.
1.1.6 Nonbuilding standards, orders, and regulations. Requirements contained in the California Wildland-Urban Interface Code, or in any other referenced standard, code, or document, which are not building standards as defined in Health and Safety Code, Section 18909 shall not be construed as a building standard. The nonbuilding standards contained herein are applicable in the wildland inter- face areas and can be cited as a section of this code, or where the section is identified on the tagline by the source document, the provision can be cited under the source document.
1.1.7 Order of precedence and use.
1.1.7.1 Differences. In the event of any differences between these building standards and the standard reference documents, the text of these building standards shall govern.
1.1.7.2 Specific provisions. Where a specific provision varies from a general provision, the specific provision shall apply.
1.1.7.3 Conflicts. When the requirements of this code conflict with the requirements of any other part of the California Building Stan- dards Code, Title 24, the most restrictive requirements shall prevail.
1.1.7.3.1 CBC and CRC. Detached one- and two-family dwellings, efficiency dwelling units, lodging houses, live/work units, and townhouses not more than three stories above grade plane with a separate means of egress, and their accessory structures, may be designed and constructed in accordance with the California Building Code or the California Residential Code, but not both, unless the proposed structure(s) or element(s) exceed the design limitations established in the California Residential Code, and the code user is specially directed by the California Residential Code to use the California Building Code.
1.1.8 City, county, or city and county amendments, additions or deletions. The provisions of this code do not limit the authority of city, county, or city and county governments to establish more restrictive and reasonably necessary differences to the provisions
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ADMINISTRATION
CRC § 2-5 Medium relevance — show source text
Part II—Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-5
CHAPTER 2 DEFINITIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . .2-5
R201 General. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-5
R202 Definitions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-5
Part III—Building Planning and Construction . . . . . . . . . . . .3-5
CHAPTER 3 BUILDING PLANNING . . . . . . . . . . . . . . . . . . . . .3-5
R300 Site Drainage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-5
R301 Design Criteria . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-5
R302 Fire-Resistant Construction . . . . . . . . . . . . . . . . . . . . 3-23
R303 Foam Plastic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-31
R304 Protection of Wood and Wood-Based Products
Against Decay . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-33
R305 Protection Against Subterranean Termites. . . . . . . 3-35
R306 Flood-Resistant Construction. . . . . . . . . . . . . . . . . . . 3-36
R307 Storm Shelters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-40
R308 Site Address . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-40
R309 Automatic Sprinkler Systems . . . . . . . . . . . . . . . . . . . 3-41
R310 Smoke Alarms. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-54
R311 Carbon Monoxide Alarms. . . . . . . . . . . . . . . . . . . . . . . 3-58
R312 Minimum Room Areas . . . . . . . . . . . . . . . . . . . . . . . . . 3-59
R313 Ceiling Height . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-59
CRC § 1-18 Medium relevance — show source text
R104 Duties and Powers of the Building Official . . . . . . . 1-18
R105 Permits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-20
R106 Construction Documents . . . . . . . . . . . . . . . . . . . . . . 1-22
R107 Temporary Structures and Uses . . . . . . . . . . . . . . . . 1-23
R108 Fees . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-23
R109 Inspections. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-23
R110 Certificate of Occupancy. . . . . . . . . . . . . . . . . . . . . . . 1-25
R111 Service Utilities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-25
R112 Means of Appeals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-25
R113 Violations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-26
R114 Stop Work Order . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-26
Part II—Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-5
CHAPTER 2 DEFINITIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . .2-5
R201 General. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-5
R202 Definitions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-5
Part III—Building Planning and Construction . . . . . . . . . . . .3-5
CHAPTER 3 BUILDING PLANNING . . . . . . . . . . . . . . . . . . . . .3-5
R300 Site Drainage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-5
R301 Design Criteria . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-5
R302 Fire-Resistant Construction . . . . . . . . . . . . . . . . . . . . 3-23
CRC § 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)]
CRC § 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.)
CRC § 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
CRC § 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.
CRC § 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: †
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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.
CRC § 104.2.2 Medium relevance — show source text
Evaluation of the hazard is a strongly subjective process; therefore, the person charged with this responsibility must gather as much relevant data as possible so that the decision will be objective and within the limits prescribed in laws, policies and standards.
It could be necessary to cause the responsible persons in charge to have tests made by qualified persons or testing laboratories to support contentions that a particular material or process is or is not hazardous. See Section 104.2.2
SECTION E104—GHS HAZARDOUS MATERIALS DEFINITIONS
E104.1 Hazardous materials definitions. The categorization and classification of hazardous materials enables the code user to determine the applicability of requirements based on hazard category and class related to the physical and health hazards of materials. The current definitions found in Chapter 2 have been developed using criteria found in NFPA codes and standards, model fire prevention codes, NIOSH, and requirements of the US Department of Transporation (DOTn 49 CFR)and US Department of Labor (DOL 49 CFR 1910).
The chemical industry has grown substantially since the inception of the CFC hazard definitions. Large-scale global production and distribution of common and specialty chemicals has become mainstream. In the 1990s, the United Nations (UN) developed the Globally Harmonized System of Classification and Labelling of Chemicals (GHS) to create international congruency among chemical suppliers. The GHS is an internationally agreed upon standard of classification and labeling that utilizes prescriptive, standardized testing procedures and criteria to classify hazardous materials.
The DOL published a revised Hazard Communication Standard (DOL 29 CFR 1910.1200) to align with the GHS in March 2012. It became effective in May 2012. All manufacturers selling, producing or transporting chemicals in the United States are now required to comply with the GHS and provide this standardized hazard information on all Safety Data Sheets (SDS).
SDS are a primary source of information for identifying hazards for chemicals and mixtures containing hazardous materials. It can be helpful for fire code officials to become familiar with the GHS definitions and how they relate to CFC hazard definitions.
E104.2 GHS hazardous materials definitions comparison table. Table E104.2 provides a tabular presentation of the various definitions published within the California Fire Code . In addition, the table presents corresponding definitions, where available, from the 2012 edition of DOL 29 CFR 1910.1200 along with applicable hazard statement codes. DOL 29 CFR 1910.1200 aligns with the UN’s Globally Harmonized System of Classification and Labelling of Chemicals (GHS) . The table is not meant to imply perfect alignment between CFC and GHS definitions.
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APPENDIX E—HAZARD CATEGORIES
Frequently asked questions
When should I look in Title 24 for a definition?
When a term is not defined in CRC Chapter 2. The CRC requires you to use the Title 24 meaning in that case (see § R201.3).
If CRC and a Title 24 part define the same term differently, which wins?
If CRC provides a definition, that CRC definition controls for the CRC text (see § R201.1). Only when the CRC is silent does § R201.3 defer to Title 24.
Does the CRC point to specific Parts of Title 24 (CBC, CMC, CPC, etc.)?
§ R201.3 defers generally to the California Building Standards Code (Title 24). You must search the appropriate Title 24 Part (for example the California Building Code) to find the specific adopted definition.
What if no definition exists in the CRC or Title 24?
Apply the ordinarily accepted meaning implied by the context per § R201.4. Document your interpretation.
Do local amendments change this deferral process?
Local amendments may adopt different definitions; always check local adoptions/amendments and their effective scope alongside CRC Chapter 1 administrative provisions.
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