CBC · California Building Code

What are the fire‑performance requirements for interior floor finishes?

For homeowners: the CBC requires many floor coverings (especially carpets) to pass standardized fire tests — they must meet a critical radiant flux threshold (Class I or II) and a smoke‑generation limit, be tested as installed (carpet plus pad), and carry a label and test report; simple hard floors like wood or vinyl are often excepted in ordinary areas.

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Last reviewed: July 5, 2026

What the code requires — 2–4 sentences

Interior floor finish and floor covering materials must meet performance tests and classification thresholds so floor materials do not exacerbate fire growth or smoke generation. The CBC requires classification by ASTM E648 / NFPA 253 and sets minimum critical radiant flux values for Class I and II (see § 804.2) and requires ASTM E648 performance plus a specific optical density limit per ASTM E662 (see § 804.1).

Requirements in detail

Scope and basic rule

  • Interior floor finish and floor covering materials are regulated by Section 804; materials must comply with the testing, classification and identification requirements found in that section. § 804.1.
  • A limited exception allows “traditional” non‑fiber floor finishes (for example wood, vinyl, linoleum, terrazzo and resilient non‑fiber coverings) to be treated differently in areas other than Group I-2 detention and Group I-3. § 804.1 (Exception).

Classification (numeric thresholds)

Floor coverings required to be Class I or Class II must be classified by ASTM E648 or NFPA 253. The numeric thresholds are: Class I = 0.45 watts/cm2 or greater; Class II = 0.22 watts/cm2 or greater. § 804.2.

Required tests and smoke limit

  • In all occupancies, interior floor finish and floor covering materials must comply with ASTM E648 (also referenced as NFPA 253) and must have a specific optical density by ASTM E662 not to exceed 450. § 804.4.1 (and related testing text).
  • Carpet-type coverings must be tested as installed (including underlayment/padding) — the unit as proposed for use. § 804.3.2.

Where Class I vs Class II is required

  • In stairways, ramps, exit passageways, corridors and rooms/open spaces not separated from corridors by full‑height partitions, minimum critical radiant flux requirements apply:
    • Class I (0.45 W/cm2) is required in certain higher‑hazard areas (for example specified I‑2/I‑3 areas and some R‑2.1 locations).
    • Class II (0.22 W/cm2) is required in many occupancies (A, B, E, H, I‑4, M, R‑1, R‑2, S, etc.). § 804.4.2 and related text.
  • The California Fire Code repeats and expands some application details (see CFC §804.3.3.2).

Identification and documentation

  • Products must be tested by an approved agency and identified by hang‑tag or other suitable method showing manufacturer/supplier, style and the floor classification. Test reports must be made available to the building official on request. § 804.3.

Decision‑relevant summary table

Decision factor Required value / action Code reference
Test standard for classification ASTM E648 or NFPA 253 § 804.2
Class I numeric threshold (critical radiant flux) ≥ 0.45 W/cm² § 804.2
Class II numeric threshold (critical radiant flux) ≥ 0.22 W/cm² § 804.2
Smoke limitation Specific optical density ≤ 450 (ASTM E662) § 804.4.1
Carpet testing Test carpet + underlayment/padding as a unit § 804.3.2
Identification Hang‑tag or equivalent showing classification § 804.3
Exception for traditional non‑fiber materials Wood, vinyl, linoleum, terrazzo and resilient non‑fiber coverings (in areas except certain I‑2/I‑3) § 804.1 (Exception)

Exceptions & special cases

  • Traditional, non‑fiber floor finishes (wood, vinyl, linoleum, terrazzo, resilient non‑fiber) are excepted in most areas (the § 804.1 exception) — but not in Group I‑2 detention or Group I‑3. § 804.1 (Exception).
  • Where a building is protected throughout by an approved automatic sprinkler system, the code permits relaxation: Class II may be allowed where Class I would otherwise be required, and ASTM E648 + ASTM E662 compliance can substitute where Class II is required (see the sprinkler exception in the Fire Code / CBC cross‑references). CFC §804.3.3.2 / CBC cross references.
  • Group I‑2 areas where patients are restrained and Group I‑3 inmate areas have stricter rules in the Fire Code: certain occupied surfaces must be noncombustible; carpeting in such areas has additional required testing and labeling if used under sprinkler protection. See CFC §804.3.3.3.

Common mistakes

  • Assuming the manufacturer’s carpet sample alone is adequate — carpet must be tested as installed, including pad/underlayment per § 804.3.2.
  • Missing the ASTM E662 smoke limit (optical density ≤ 450). Passing only the critical radiant flux test (E648) is not sufficient; the E662 smoke criterion is a separate requirement in § 804.4.1.
  • Misapplying the “traditional floor” exception to fiber‑based resilient products or carpets — the exception explicitly lists non‑fiber traditional types and excludes fiber floor coverings in many locations (§ 804.1 Exception).
  • Failing to keep or present test reports / hang‑tags: identification and test reports must be available to the building official per § 804.3.

Worked example

Scenario: You are specifying new carpet for the corridor of an apartment building (Group R‑2). Corridors are among the locations the code protects by minimum radiant flux rules.

Step 1 — Determine required class:

  • Corridors in Group R‑2 are listed where Class II minimum is required (see § 804.4.2). Required → Class II (critical radiant flux ≥ 0.22 W/cm²).

Step 2 — Check lab results (example values):

  • Manufacturer test report (carpet + pad as installed) shows ASTM E648 critical radiant flux = 0.25 W/cm² → meets Class II (≥ 0.22).
  • ASTM E662 specific optical density = 300 → meets the ≤ 450 smoke limit in § 804.4.1.

Step 3 — Documentation and labeling:

  • The roll/box bears a hang‑tag showing the product classification and manufacturer; the installer retains the test report for the building official per § 804.3.

Conclusion: With CRF = 0.25 W/cm² and smoke density = 300, the carpet (tested as installed) complies for the R‑2 corridor. If instead the CRF had been 0.18 W/cm², it would fail Class II and be unacceptable; you would need a different product or a sprinkler‑system solution per the applicable sprinkler exception.

Related provisions

  • § 804.3 — Testing and identification requirements (hang‑tag, test reports).
  • § 804.4.1 — ASTM E648 requirement and ASTM E662 smoke limit (reiterated).
  • § 804.4.2 — Minimum critical radiant flux application locations (stairways, corridors, exits).
  • CFC § 804.3.3.2 / § 804.3.3.1 — Fire Code text on minimum CRF and smoke limits, and sprinkler exceptions.
  • § 803.1.1 / § 803.1.2 — Related interior finish testing methods and acceptance criteria (wall/ceiling materials).
  • § 806.7 — Interior floor‑wall base requirements (floor‑wall base tested per § 804.2).
  • § 903.3.1.1 — Automatic sprinkler system thresholds referenced for exceptions. (See sprinkler‑system exception language in § 804.x and the Fire Code.)

Code references

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

  • CBC § 803.13 High relevance — show source text

    1||X||||||||||||||||||||||| |Table 803.13|||X|||||||||||||||||||||| |804.1|||X|||||||||||||||||||||| |804.4|||X|||||||||||||||||||||| |804.4.1|||X|||||||||||||||||||||| |804.4.2|||X|||||||||||||||||||||| |804.4.3|||X|||||||||||||||||||||| |806.4|||X|||||||||||||||||||||| |806.6|||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.

    2025 CALIFORNIA BUILDING CODE 8-1

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    8-2 2025 CALIFORNIA BUILDING CODE

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    8 INTERIOR FINISHES

    User notes:

    About this chapter: Chapter 8 contains the performance requirements for controlling fire growth and smoke propagation within buildings by restricting interior finish and decorative materials. The provisions of this chapter require materials used as interior finishes and decorations to meet certain flame spread index or flame propagation criteria and smoke development criteria based on the relative fire hazard associated with the occupancy. The performance of the material is evaluated based on test standards.

    SECTION 801—SCOPE

    801.1 Scope. The provisions of this chapter shall govern the use of materials used as interior finishes, trim and decorative materials.

    [BSC-CG] See California Green Building Standards Code, Chapter 5, Division 5.5 for additional finish material pollutant control requirements.

    SECTION 802—GENERAL

    802.1 Interior wall and ceiling finish. The provisions of Section 803 shall limit the allowable fire performance and smoke development of interior wall and ceiling finish materials based on occupancy classification.

    802.2 Interior floor finish. The provisions of Section 804 shall limit the allowable fire performance of interior floor finish materials based on occupancy classification.

    [F] 802.3 Decorative materials and trim. Decorative materials and trim shall be restricted by combustibility, fire performance or flame propagation performance criteria in accordance with Section 806.

    802.4 Applicability. For buildings in flood hazard areas as established in Section 1612.3, interior finishes, trim and decorative materials below the elevation required by Section 1612 shall be flood-damage-resistant materials.

    802.5 Application. Combustible materials shall be permitted to be used as finish for walls, ceilings, floors and other interior surfaces of buildings.

    802.6 Windows. Show windows in the exterior walls of the first story above grade plane shall be permitted to be of wood or of unprotected metal framing.

    802.7 Foam plastics. Foam plastics shall not be used as interior finish except as provided in Section 803.4. Foam plastics shall not be used as interior trim except as provided in Section 806.6.1 or 2604.2. This section shall apply both to exposed foam plastics and to foam plastics used in conjunction with a textile or vinyl facing or cover.

    SECTION 803—WALL AND CEILING FINISHES

  • CBC § 5.5 High relevance — show source text

    [BSC-CG] See California Green Building Standards Code, Chapter 5, Division 5.5 for additional finish material pollutant control requirements.

    SECTION 802—GENERAL

    802.1 Interior wall and ceiling finish. The provisions of Section 803 shall limit the allowable fire performance and smoke development of interior wall and ceiling finish materials based on occupancy classification.

    802.2 Interior floor finish. The provisions of Section 804 shall limit the allowable fire performance of interior floor finish materials based on occupancy classification.

    [F] 802.3 Decorative materials and trim. Decorative materials and trim shall be restricted by combustibility, fire performance or flame propagation performance criteria in accordance with Section 806.

    802.4 Applicability. For buildings in flood hazard areas as established in Section 1612.3, interior finishes, trim and decorative materials below the elevation required by Section 1612 shall be flood-damage-resistant materials.

    802.5 Application. Combustible materials shall be permitted to be used as finish for walls, ceilings, floors and other interior surfaces of buildings.

    802.6 Windows. Show windows in the exterior walls of the first story above grade plane shall be permitted to be of wood or of unprotected metal framing.

    802.7 Foam plastics. Foam plastics shall not be used as interior finish except as provided in Section 803.4. Foam plastics shall not be used as interior trim except as provided in Section 806.6.1 or 2604.2. This section shall apply both to exposed foam plastics and to foam plastics used in conjunction with a textile or vinyl facing or cover.

    SECTION 803—WALL AND CEILING FINISHES

    803.1 General. Interior wall and ceiling finish materials shall be classified for fire performance and smoke development in accordance with Section 803.1.1 or 803.1.2, except as shown in Sections 803.1.3 through 803.15. Materials tested in accordance with Section 803.1.1 shall not be required to be tested in accordance with Section 803.1.2.

    803.1.1 Interior wall and ceiling finish materials tested in accordance with NFPA 286. Interior wall and ceiling finish materials shall be classified in accordance with NFPA 286 and comply with Section 803.1.1.1. Materials complying with Section 803.1.1.1 shall be considered to also comply with the requirements of Class A.

    803.1.1.1 Acceptance criteria for NFPA 286. The interior finish shall comply with the following:

    1. During the 40 kW exposure, flames shall not spread to the ceiling.

    2. The flame shall not spread to the outer extremity of the sample on any wall or ceiling.

    3. Flashover, as defined in NFPA 286, shall not occur.

    4. The peak heat release rate throughout the test shall not exceed 800 kW.

    5. The total smoke released throughout the test shall not exceed 1,000 m [2] .

    803.1.2 Interior wall and ceiling finish materials tested in accordance with ASTM E84 or UL 723. Interior wall and ceiling finish materials shall be classified in accordance with ASTM E84 or UL 723. Such interior finish materials shall be grouped in the following classes in accordance with their flame spread and smoke-developed indices.

    Class A = Flame spread index 0–25; smoke-developed index 0–450.

    Class B = Flame spread index 26–75; smoke developed index 0–450.

    Class C = Flame spread index 76–200; smoke-developed index 0–450.

  • CBC § 804.3.3 High relevance — show source text

    804.3.3 Interior floor finish requirements. New interior floor covering materials shall comply with Sections 804.3.3.1 and 804.3.3.2, and interior floor finish materials shall comply with Section 804.3.1.

    804.3.3.1 Test requirement. In all occupancies, interior floor finish and interior floor covering materials shall comply with the requirements of ASTM Standard E648, and having a specific optical density smoke rating not to exceed 450 per ASTM E662. For Group I-3 occupancies and Group I-2 areas where patients are restrained, see Section 804.3.3.3.

    804.3.3.2 Minimum critical radiant flux. In all occupancies, new interior floor finish and floor covering materials in enclosures for stairways and ramps, exit passageways, corridors and rooms or spaces not separated from corridors by full-height partitions extending from the floor to the underside of the ceiling shall withstand a minimum critical radiant flux. The minimum critical radiant flux shall be not less than Class I in Groups I-2 and I-3 areas where restraint is not used and R-2.1 and not less than Class II in Groups A, B, E, H, I-4, M, R-1, R-2, R-2.2 and S.

    Exception: Where a building is equipped throughout with an automatic sprinkler system in accordance with Section 903.3.1.1 or 903.3.1.2, Class II materials shall be permitted in any area where Class I materials are required and materials complying with ASTM Standard E648, and having a specific optical density smoke rating not to exceed 450 per ASTM E662 are permitted in any area where Class II materials are required.

    For Group I-3 areas occupied by inmates or Group I-2 areas where patients are restrained, see Section 804.3.3.3.

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    INTERIOR FINISH, DECORATIVE MATERIALS AND FURNISHINGS

    804.3.3.3 Group I-2 and Group I-3 floor surfaces. Interior floor finish and floor coverings occupied by inmates or patients whose personal liberties are restrained shall be noncombustible. Carpet or other floor covering materials may be used in areas protected by an automatic sprinkler system installed throughout in accordance with Section 903.3.1.1. Carpet or other floor coverings shall comply with the requirements of ASTM Standard E648; the minimum critical radiant flux shall be not less than Class I and the specific optical density smoke rating shall not exceed 450 per ASTM E662. Carpeting and carpet padding shall be tested as a unit in accordance with floor covering radiant panel test meeting Class 1 and has a critical radiant flux limit of not less than 0.45 watt per centimeter square. The carpeting and padding shall be identified by a hang-tag or other suitable method as to manufacturer and style and shall indicate the classification of the material based on the limits set forth above.

  • CBC § 806.4 High relevance — show source text

    [F] 806.4 Acceptance criteria and reports. Where required to exhibit improved fire performance, curtains, draperies, fabric hangings and similar combustible decorative materials suspended from walls or ceilings shall be tested by an approved agency and shall be flame resistant in accordance with the provisions set forth in CCR, Title 19, Division 1, Chapter 8 . Reports of test results shall be prepared in accordance with the test method used and furnished to the building official on request.

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    INTERIOR FINISHES

    [F] 806.5 Pyroxylin plastic. Imitation leather or other material consisting of or coated with a pyroxylin or similarly hazardous base shall not be used in Group A occupancies.

    [F] 806.6 Interior trim. Material, other than foam plastic used as interior trim, shall have a minimum Class B flame spread and 450 smoke-developed index in Group I-3 and for all other occupancies Class C flame spread and smoke-developed index when tested in accordance with ASTM E84 or UL 723, as described in Section 803.1.2. Combustible trim, excluding handrails and guardrails, shall not exceed 10 percent of the specific wall or ceiling area to which it is attached.

    [F] 806.6.1 Foam plastic. Foam plastic used as interior trim in any occupancy shall comply with Section 2604.2.

    [F] 806.7 Interior floor-wall base. Interior floor-wall base that is 6 inches (152 mm) or less in height shall be tested in accordance with Section 804.2 and shall be not less than Class II. Where a Class I floor finish is required, the floor-wall base shall be Class I.

    Exception: Interior trim materials that comply with Section 806.6.

    [F] 806.8 Combustible lockers. Where lockers constructed of combustible materials are used, the lockers shall be considered to be interior finish and shall comply with Section 803.

    Exception: Lockers constructed entirely of wood and noncombustible materials shall be permitted to be used wherever interior finish materials are required to meet a Class C classification in accordance with Section 803.1.2.

    SECTION 807—INSULATION

    807.1 Insulation. Thermal and acoustical insulation shall comply with Section 720.

    SECTION 808—ACOUSTICAL CEILING SYSTEMS

    808.1 Acoustical ceiling systems. The quality, design, fabrication and erection of metal suspension systems for acoustical tile and lay-in panel ceilings in buildings or structures shall conform to generally accepted engineering practice, the provisions of this chapter and other applicable requirements of this code.

    808.1.1 Materials and installation. Acoustical materials complying with the interior finish requirements of Section 803 shall be installed in accordance with the manufacturer’s recommendations and applicable provisions for applying interior finish.

    808.1.1.1 Suspended acoustical ceilings. Suspended acoustical ceiling systems shall be installed in accordance with the provisions of ASTM C635 and ASTM C636.

    808.1.1.2 Fire-resistance-rated construction. Acoustical ceiling systems that are part of fire-resistance-rated construction shall be installed in the same manner used in the assembly tested and shall comply with the provisions of Chapter 7.

  • CBC § 802.1 High relevance — show source text

    SECTION 802—DEFINITIONS

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

    FLAME SPREAD.

    FLAME SPREAD INDEX.

    INTERIOR FLOOR-WALL BASE.

    SITE-FABRICATED STRETCH SYSTEM.

    SMOKE-DEVELOPED INDEX.

    [California Code of Regulations, Title 19, Division 1, §1191] Approved.

    “Approved” means approved by the State Fire Marshal.

    [California Code of Regulations, Title 19, Division 1, §1196] Flame-retardant Chemical.

    “Flame-Retardant Chemical,” as used herein, means any chemical, chemical compound or chemical mixture which when properly applied to a fabric or material will render such fabric or material incapable of supporting combustion to the extent that it will success- fully withstand the tests and meet the specifications promulgated by the State Fire Marshal.

    [California Code of Regulations, Title 19, Division 1, §1201] Nonflammable Material.

    “Nonflammable Material,” as used herein, means a fabric or material which is inherently flame-resistant to the extent that it will meet the requirements of the fire resistance test herein prescribed, but shall not include materials which must be chemically treated or processed after manufacture to make them flame-resistant.

    [California Code of Regulations, Title 19, Division 1, §1202] Place of Public Assemblage.

    “Place of Public Assemblage,” as used herein, means any occupancy mentioned in Sections 13115 or 13119 of the Health and Safety Code.

    2025 CALIFORNIA FIRE CODE 8-3

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    INTERIOR FINISH, DECORATIVE MATERIALS AND FURNISHINGS

    SECTION 803—INTERIOR WALL AND CEILING FINISH IN EXISTING BUILDINGS

    803.1 General. The provisions of this section shall limit the allowable fire performance and smoke development of interior wall and ceiling finishes in existing buildings based on location and occupancy classification. Interior wall and ceiling finishes shall be classified in accordance with Section 803 of the California Building Code . Such materials shall be classified in accordance with NFPA 286, as indicated in Section 803.1.1, or in accordance with ASTM E84 or UL 723, as indicated in Section 803.1.2.

    Materials tested in accordance with Section 803.1.1 shall not be required to be tested in accordance with Section 803.1.2.

    803.1.1 Interior wall and ceiling finish materials tested in accordance with NFPA 286. Interior wall and ceiling finish materials shall be classified in accordance with NFPA 286 and tested in accordance with Section 803.1.1.1. Materials complying with Section 803.1.1.1 shall be considered to comply with the requirements of Class A specified in Section 803.1.2.

    803.1.1.1 Acceptance criteria for NFPA 286. The interior finish shall comply with the following:

    1. During the 40 kW exposure, flames shall not spread to the ceiling.

    2. The flame shall not spread to the outer extremity of the sample on any wall or ceiling.

    3. Flashover, as defined in NFPA 286, shall not occur.

    4. The peak heat release rate throughout the test shall not exceed 800 kW.

    5. The total smoke released throughout the test shall not exceed 1,000 m [2] .

  • CBC § 803.1.1 High relevance — show source text

    Exceptions:

    1. Noncombustible interior finish materials.

    2. Materials that meet the requirements of Class A materials in accordance with Section 803.1.1 or 803.1.2 where the qualifying tests were made with the material furred out from the noncombustible backing shall be permitted to be used with furring strips.

    3. Materials that meet the requirements of Class A materials in accordance with Section 803.1.1 or 803.1.2 where the qualifying tests were made with the material suspended away from the noncombustible backing shall be permitted to be used suspended away from the building element.

    SECTION 804—INTERIOR FLOOR FINISH

    804.1 General. Interior floor finish and floor covering materials shall comply with Sections 804.2 through 804.4.2.

    Exception: In areas except Groups I-2 with detention and I-3, floor finishes and coverings of a traditional type, such as wood, vinyl, linoleum or terrazzo, and resilient floor covering materials that are not composed of fibers.

    804.2 Classification. Interior floor finish and floor covering materials required by Section 804.4.2 to be of Class I or II materials shall be classified in accordance with ASTM E648 or NFPA 253. The classification referred to herein corresponds to the classifications determined by ASTM E648 or NFPA 253 as follows: Class I, 0.45 watts/cm [2] or greater; Class II, 0.22 watts/cm [2] or greater.

    804.3 Testing and identification. Interior floor finish and floor covering materials shall be tested by an agency in accordance with ASTM E648 or NFPA 253 and identified by a hang tag or other suitable method so as to identify the manufacturer or supplier and style, and shall indicate the interior floor finish or floor covering classification in accordance with Section 804.2. Carpet-type floor coverings shall be tested as proposed for use, including underlayment. Test reports confirming the information provided in the manufacturer’s product identification shall be furnished to the building official on request.

    804.4 Interior floor finish requirements. Interior floor covering materials shall comply with Sections 804.4.1 and 804.4.2 and interior floor finish materials shall comply with Section 804.4.3 .

    804.4.1 Test requirement. In all occupancies, interior floor finish and interior floor covering materials shall comply with the requirements of the ASTM Standard E648, and having a specific optical density smoke rating not to exceed 450 per ASTM E662. For Group I-3 occupancies and Group I-2 areas where patients are restrained, see Section 804.4.3.

    804.4.2 Minimum critical radiant flux. In all occupancies, interior floor finish and floor covering materials in enclosures for stairways and ramps, exit passageways, corridors and rooms or spaces not separated from corridors by partitions extending from the floor to the underside of the ceiling shall withstand a minimum critical radiant flux. The minimum critical radiant flux shall be not less than Class I in Groups I-2 and I-3 areas where restraint is not used and R-2.1 and not less than Class II in Groups A, B, E, H, I-4, M, R-1, R-2, R-2.2 and S . For Group I-3 areas occupied by inmates or Group I-2 areas where patients are restrained, see Section 804.4.3.

  • CWUIC § 2025 High relevance — show source text

    2025 CALIFORNIA BUILDING CODE xiii

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    Chapter 7 Fire and Smoke Protection Features.

    Chapter 7 provisions present the fundamental concepts of fire performance that all buildings are expected to achieve in some form. This chapter identifies the acceptable materials, techniques and methods by which proposed construction can be designed and evaluated against to determine a building’s ability to limit the impact of fire.

    Chapter 7A Materials and Construction Methods for Exterior Wildfire Exposure.

    Requirements for Wildland-Urban Interface Areas are now located in Part 7 of Title 24, California Wildland-Urban Interface Code. The provisions of Part 7, California Wildland-Urban Interface Code, shall apply to buildings and structures located in the wildland-urban interface (WUI) or Fire Hazard Severity Zone.

    Chapter 8 Interior Finishes.

    Chapter 8 contains the performance requirements for controlling fire growth within buildings by restricting interior finish and decorative materials. The provisions of Chapter 8 require materials used as interior finishes and decorations to meet certain flame-spread index or flame-propagation criteria based on the relative fire hazard associated with the occupancy.

    Chapter 9 Fire Protection and Life Safety Systems.

    Chapter 9 prescribes the minimum requirements for active systems of fire protection equipment to perform the following functions: detect a fire, alert the occupants or fire department of a fire emergency, and control smoke and control or extinguish the fire. Generally, the requirements are based on the occupancy, the height and the area of the building, because these are the factors that most affect firefighting capabilities and the relative hazard of a specific building or portion thereof. This chapter parallels and is substantially duplicated in Chapter 9 of the CFC; however, the CFC Chapter 9 also contains periodic testing criteria that are not contained in the CBC. In addition, the special fire protection system requirements based on use and occupancy found in CBC Chapter 4 are duplicated in CFC Chapter 9 as a user convenience.

    Chapter 10 Means of Egress.

    The criteria in Chapter 10 regulating the design of the means of egress system are established as the primary method for protection of occupants by allowing timely relocation or evacuation. Both prescriptive and performance language is utilized for determination of a safe exiting system. It addresses all portions of the means of egress system (i.e., exit access, exits and exit discharge) and includes design requirements as well as provisions regulating individual components. The requirements detail the size, arrangement, number and protection of means of egress components. The means of egress protection requirements work in coordination with other sections of the code, such as protection of vertical openings (see Chapter 7), interior finish (see Chapter 8), fire suppression and detection systems (see Chapter 9) and numerous others, all having an impact on life safety. Chapter 10 of the CBC is duplicated in Chapter 10 of the CFC; however, the CFC contains one additional section on the maintenance of the means of egress system in existing buildings.

    Chapter 11 Reserved.

    Chapter 11A Housing Accessibility. Chapter 11B Accessibility to Public Buildings, Public Accommodations, Commercial Buildings and Public Housing.

    Verify compliance with accessibility provisions. In order to be considered as accessible, buildings and their individual elements must comply with the applicable scoping and technical provisions of Chapter 11A and/or Chapter 11B.

    Chapter 12 Interior Environment.

  • CBC § 804.1.1 High relevance — show source text

    804.1.1 Testing in accordance with NFPA 286. Interior trim material shall be tested in accordance with NFPA 286 and comply with the acceptance criteria in Section 803.1.1.1. Where the interior trim material has been tested as an interior finish in accordance with NFPA 286 and complies with the acceptance criteria in Section 803.1.1.1, it shall not be required to be tested for flame spread index and smoke-developed index in accordance with ASTM E84 or UL 723.

    804.1.2 Testing in accordance with ASTM E84 or UL 723. Material, other than foam plastic, used as interior trim shall have minimum Class C flame spread and smoke-developed indices, when tested in accordance with ASTM E84 or UL 723, as described in Section 803.1.2.

    804.2 Foam plastic interior trim. Foam plastic used as interior trim shall comply with Sections 804.2.1 through 804.2.4. 804.2.1 Density. The minimum density of the interior trim shall be 20 pounds per cubic foot (320 kg/m [3] ). 804.2.2 Thickness. The maximum thickness of the interior trim shall be [1] / 2 inch (12.7 mm) and the maximum width shall be 8 inches (203 mm).

    804.2.3 Area limitation. The interior trim shall not constitute more than 10 percent of the specific wall or ceiling area to which it is attached.

    804.2.4 Flame spread. The flame spread index shall not exceed 75 where tested in accordance with ASTM E84 or UL 723. The smoke-developed index shall not be limited.

    Exception: Where the interior trim material has been tested as an interior finish in accordance with NFPA 286 and complies with the acceptance criteria in Section 803.1.1.1, it is not required to be tested for flame spread index in accordance with ASTM E84 or UL 723.

    804.3 New interior floor finish. New interior floor finish and floor covering materials in new and existing buildings shall comply with Sections 804.3.1 through 804.3.3.2.

    Exception: Floor finishes and coverings of a traditional type, such as wood, vinyl, linoleum or terrazzo, and resilient floor covering materials that are not composed of fibers.

    804.3.1 Classification. Interior floor finish and floor covering materials required by Section 804.3.3.2 to be of Class I or II materials shall be classified in accordance with ASTM E648 or NFPA 253. The classification referred to herein corresponds to the classifications determined by ASTM E648 or NFPA 253 as follows: Class I, 0.45 watts/cm [2] or greater; Class II, 0.22 watts/cm [2] or greater.

    804.3.2 Testing and identification. Interior floor finish and floor covering materials shall be tested by an approved agency in accordance with ASTM E648 or NFPA 253 and identified by a hang tag or other suitable method so as to identify the manufacturer or supplier and style, and shall indicate the interior floor finish or floor covering classification in accordance with Section 804.3.1. Carpet-type floor coverings shall be tested as proposed for use, including underlayment. Test reports confirming the information provided in the manufacturer’s product identification shall be furnished to the fire code official upon request.

  • CBC § 803.1.1.1 High relevance — show source text

    Exception: Where the interior trim material has been tested as an interior finish in accordance with NFPA 286 and complies with the acceptance criteria in Section 803.1.1.1, it is not required to be tested for flame spread index in accordance with ASTM E84 or UL 723.

    804.3 New interior floor finish. New interior floor finish and floor covering materials in new and existing buildings shall comply with Sections 804.3.1 through 804.3.3.2.

    Exception: Floor finishes and coverings of a traditional type, such as wood, vinyl, linoleum or terrazzo, and resilient floor covering materials that are not composed of fibers.

    804.3.1 Classification. Interior floor finish and floor covering materials required by Section 804.3.3.2 to be of Class I or II materials shall be classified in accordance with ASTM E648 or NFPA 253. The classification referred to herein corresponds to the classifications determined by ASTM E648 or NFPA 253 as follows: Class I, 0.45 watts/cm [2] or greater; Class II, 0.22 watts/cm [2] or greater.

    804.3.2 Testing and identification. Interior floor finish and floor covering materials shall be tested by an approved agency in accordance with ASTM E648 or NFPA 253 and identified by a hang tag or other suitable method so as to identify the manufacturer or supplier and style, and shall indicate the interior floor finish or floor covering classification in accordance with Section 804.3.1. Carpet-type floor coverings shall be tested as proposed for use, including underlayment. Test reports confirming the information provided in the manufacturer’s product identification shall be furnished to the fire code official upon request.

    804.3.3 Interior floor finish requirements. New interior floor covering materials shall comply with Sections 804.3.3.1 and 804.3.3.2, and interior floor finish materials shall comply with Section 804.3.1.

    804.3.3.1 Test requirement. In all occupancies, interior floor finish and interior floor covering materials shall comply with the requirements of ASTM Standard E648, and having a specific optical density smoke rating not to exceed 450 per ASTM E662. For Group I-3 occupancies and Group I-2 areas where patients are restrained, see Section 804.3.3.3.

    804.3.3.2 Minimum critical radiant flux. In all occupancies, new interior floor finish and floor covering materials in enclosures for stairways and ramps, exit passageways, corridors and rooms or spaces not separated from corridors by full-height partitions extending from the floor to the underside of the ceiling shall withstand a minimum critical radiant flux. The minimum critical radiant flux shall be not less than Class I in Groups I-2 and I-3 areas where restraint is not used and R-2.1 and not less than Class II in Groups A, B, E, H, I-4, M, R-1, R-2, R-2.2 and S.

    Exception: Where a building is equipped throughout with an automatic sprinkler system in accordance with Section 903.3.1.1 or 903.3.1.2, Class II materials shall be permitted in any area where Class I materials are required and materials complying with ASTM Standard E648, and having a specific optical density smoke rating not to exceed 450 per ASTM E662 are permitted in any area where Class II materials are required.

  • CBC § 803.13 High relevance — show source text

    1. Aluminum composite material (ACM) meeting the requirements of Class A interior finish in accordance with Chapter 8 when tested as an assembly in the maximum thickness intended for use.

    2. Textiles and films complying with the fire propagation performance criteria contained in Test Method 1 or Test Method 2, as appropriate, of NFPA 701.

    3. Plastic materials used to construct rigid components of soft-contained play equipment structures (such as tubes, windows, panels, junction boxes, pipes, slides and decks) exhibiting a peak rate of heat release not exceeding 400 kW/ m [2] when tested in accordance with ASTM E1354 at an incident heat flux of 50 kW/m [2] in the horizontal orientation at a thickness of 6 mm.

    4. Ball pool balls, used in soft-contained play equipment structures, having a maximum heat-release rate not greater than 100 kilowatts when tested in accordance with UL 1975 or when tested in accordance with NFPA 289, using the 20 kW ignition source. The minimum specimen test size shall be 36 inches by 36 inches (914 mm by 914 mm) by an average of 21 inches (533 mm) deep, and the balls shall be held in a box constructed of galvanized steel poultry netting wire mesh.

    5. Foam plastics shall be covered by a fabric, coating or film meeting the fire propagation performance criteria contained in Test Method 1 or Test Method 2, as appropriate, of NFPA 701.

    6. The floor covering placed under the play structure shall exhibit a Class I interior floor finish classification, as described in Section 804, when tested in accordance with ASTM E648 or NFPA 253.

    7. Interior finishes for structures exceeding 600 square feet (56 m [2] ) in area or 10 feet (3048 mm) in height shall have a flame spread index not greater than that specified in Table 803.13 for the occupancy group and location designated. Interior wall and ceiling finish materials tested in accordance with NFPA 286 and meeting the acceptance criteria of Section 803.1.1.1, shall be permitted to be used where a Class A classification in accordance with ASTM E84 or UL 723 is required.

    [F] 424.3 Fire protection. Play structures shall be provided with the same level of approved fire suppression and detection devices required for other structures in the same occupancy.

    [BF] 424.4 Separation. Play structures shall have a horizontal separation from building walls, partitions and from elements of the means of egress of not less than 5 feet (1524 mm). Play structures shall have a horizontal separation from other play structures of not less than 20 feet (6090 mm).

    [BF] 424.5 Area limits. Play structures shall be not greater than 600 square feet (56 m [2] ) in area, unless a special investigation, acceptable to the building official, has demonstrated adequate fire safety.

    [BF] 424.5.1 Design. Play structures exceeding 600 square feet (56 m [2] ) in area or 10 feet (3048 mm) in height shall be designed in accordance with Chapter 16.

    SECTION 425—HYPERBARIC FACILITIES

    425.1 Hyperbaric facilities. Hyperbaric facilities shall meet the requirements contained in Chapter 14 of NFPA 99.

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    SPECIAL DETAILED REQUIREMENTS BASED ON OCCUPANCY AND USE

  • CBC § 803.13 High relevance — show source text

    803.13 Laminated products factory produced with an attached wood substrate. Laminated products factory produced with an attached wood substrate shall comply with one of the following:

    1. The laminated product shall meet the criteria of Section 803.1.1 when tested in accordance with NFPA 286 using the product mounting system, including adhesive, of actual use.
    2. The laminated product shall have a Class A, B or C flame spread index and smoke-developed index based on the requirements of Table 803.3, in accordance with ASTM E84 or UL 723. Test specimen preparation and mounting shall be in accordance with ASTM E2579.

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    INTERIOR FINISH, DECORATIVE MATERIALS AND FURNISHINGS

    803.14 Thickness exemption. Materials having a thickness less than 0.036 inch (0.9 mm) applied directly to the surface of walls or ceilings shall not be required to be tested.

    803.15 Heavy timber exemption. Exposed portions of building elements complying with the requirements of Type IV construction in accordance with the California Building Code shall not be subject to interior finish requirements.

    SECTION 804—INTERIOR WALL AND CEILING TRIM AND INTERIOR FLOOR FINISH IN NEW AND EXISTING BUILDINGS

    804.1 Interior trim. Combustible trim in new and existing buildings, excluding handrails and guards, shall not exceed 10 percent of the specific wall or ceiling areas to which it is attached. Other than foam plastic, material used as interior trim shall have minimum Class B flame spread and 450 smoke-developed index in Group I-3 and for all other occupancies shall comply with Section 804.1.1 or 804.1.2. Foam plastic used as interior trim shall comply with Section 804.2.

    804.1.1 Testing in accordance with NFPA 286. Interior trim material shall be tested in accordance with NFPA 286 and comply with the acceptance criteria in Section 803.1.1.1. Where the interior trim material has been tested as an interior finish in accordance with NFPA 286 and complies with the acceptance criteria in Section 803.1.1.1, it shall not be required to be tested for flame spread index and smoke-developed index in accordance with ASTM E84 or UL 723.

    804.1.2 Testing in accordance with ASTM E84 or UL 723. Material, other than foam plastic, used as interior trim shall have minimum Class C flame spread and smoke-developed indices, when tested in accordance with ASTM E84 or UL 723, as described in Section 803.1.2.

    804.2 Foam plastic interior trim. Foam plastic used as interior trim shall comply with Sections 804.2.1 through 804.2.4. 804.2.1 Density. The minimum density of the interior trim shall be 20 pounds per cubic foot (320 kg/m [3] ). 804.2.2 Thickness. The maximum thickness of the interior trim shall be [1] / 2 inch (12.7 mm) and the maximum width shall be 8 inches (203 mm).

    804.2.3 Area limitation. The interior trim shall not constitute more than 10 percent of the specific wall or ceiling area to which it is attached.

  • CBC § 509.1 High relevance — show source text

    Unique consideration is taken for special use areas, such as covered mall buildings, motor-vehicle-related occupancies, special amusement buildings and aircraftrelated occupancies. Special facilities within other occupancies are considered, such as stages and platforms, motion picture projection rooms, children’s play structures and storm shelters. Finally, in order that the overall package of protection features can be easily understood, unique considerations for specific occupancies are also addressed.

    Chapter 5 General Building Heights and Areas.

    Chapter 5 contains the provisions that regulate the minimum type of construction for area limits and height limits based on the occupancy of the building. Height and area increases are permitted based on open frontage for fire department access, separation and the type of sprinkler protection provided (Sections 503 through 506, 510). Provisions include the protection and/or separation of incidental uses (Table 509.1), accessory occupancies (Section 508.2) and mixed uses in the same building (Sections 506.2.2, 508.3, 508.4 and 510). Unlimited area buildings are permitted in certain occupancies when they meet special provisions (Section 507). Live/work units are provided for in Section 508.5.

    Tables 504.3, 504.4 and 506.2 are the keystones in setting thresholds for building size based on the building’s use and the materials with which it is constructed. Respective to each group classification, the greater the fire-resistance rating of structural elements, as represented by the type of construction, the greater the floor area and height allowances. The greater the potential fire hazards indicated as a function of the group, the lesser the height and area allowances for a particular construction type.

    Chapter 6 Types of Construction.

    The interdependence of fire safety considerations can be seen by looking at Tables 601 and 705.5, which show the fire-resistance ratings of the principal structural elements comprising a building in relation to the five classifications for types of construction. Type I construction generally requires the highest fire-resistance ratings for structural elements, whereas Type V construction generally requires the least amount of fire-resistance-rated structural elements. The greater the potential fire hazards indicated as a function of the group, the lesser the height and area allowances for a particular construction type. Section 603 includes a list of combustible elements that can be part of a noncombustible building (Types I and II construction).

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    Chapter 7 Fire and Smoke Protection Features.

    Chapter 7 provisions present the fundamental concepts of fire performance that all buildings are expected to achieve in some form. This chapter identifies the acceptable materials, techniques and methods by which proposed construction can be designed and evaluated against to determine a building’s ability to limit the impact of fire.

    Chapter 7A Materials and Construction Methods for Exterior Wildfire Exposure.

    Requirements for Wildland-Urban Interface Areas are now located in Part 7 of Title 24, California Wildland-Urban Interface Code. The provisions of Part 7, California Wildland-Urban Interface Code, shall apply to buildings and structures located in the wildland-urban interface (WUI) or Fire Hazard Severity Zone.

    Chapter 8 Interior Finishes.

    Chapter 8 contains the performance requirements for controlling fire growth within buildings by restricting interior finish and decorative materials. The provisions of Chapter 8 require materials used as interior finishes and decorations to meet certain flame-spread index or flame-propagation criteria based on the relative fire hazard associated with the occupancy.

    Chapter 9 Fire Protection and Life Safety Systems.

Frequently asked questions

Do all floor coverings have to be tested?

Not all: the code excepts traditional non‑fiber finishes (wood, vinyl, linoleum, terrazzo, resilient non‑fiber) in most areas per § 804.1 (Exception); otherwise covering materials that are required to meet Class I/II must be tested.

How is carpet tested?

Carpet must be tested as it will be installed — that includes the underlayment/pad — and the report must show compliance with ASTM E648/NFPA 253 classification and the ASTM E662 smoke limit when applicable (§ 804.3.2, § 804.4.1).

What does Class I vs Class II mean in plain terms?

Class I indicates a higher minimum critical radiant flux (≥ 0.45 W/cm²) than Class II (≥ 0.22 W/cm²); the higher the number, the more resistant the floor covering is to sustained ignition/propagation under the test method (§ 804.2).

If my building has sprinklers, can I use a lower class?

There is a code exception that, where a building is fully sprinklered per the referenced sprinkler sections, allows Class II where Class I would otherwise be required; see the sprinkler exception language in the Fire Code/CBC cross references.

What documentation should I keep on site?

Keep the manufacturer’s hang‑tag and the full test report showing the ASTM E648/NFPA 253 classification and ASTM E662 smoke result; the building official may request these per § 804.3.

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