CBC · California Building Code

Labeling, testing and manufacturer data for FRTW and panels

The CBC requires every fire‑retardant‑treated board and panel to be permanently labeled with an approved agency mark, manufacturer/treatment/species and flame/spread/smoke numbers; panels must be fire‑tested with a 1/8‑in. ripped gap and manufacturers must publish treatment adjustment factors and allowable spans based on the ASTM test standards cited in §§ 2303.2.1, 2303.2.4 and 2303.2.5 .

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Last reviewed: July 5, 2026

What the code requires — 2–4 sentences

Every piece of fire‑retardant‑treated lumber and fire‑retardant‑treated wood structural panel must carry a permanent label showing the approved agency mark, the treating manufacturer and treatment, species, flame spread and smoke indices, method of drying and conformance information. Panels must be fire‑tested with a ripped or cut longitudinal gap of 1/8 in. and treatments must meet the ASTM/UL flame‑spread criteria (flame spread ≤ 25) or the alternate ASTM E2768 procedure as specified in the CBC. These labeling and test requirements are set out in § 2303.2.5, § 2303.2.4 and § 2303.2.1 of the CBC .

Requirements in detail

Required label content (what must appear on each piece)

Each piece of FRT lumber and FRT wood structural panel must be labeled and the label must include:

  • identification mark of an approved agency (per labeling procedures in Chapter 17),
  • treating manufacturer's identity,
  • name of the fire‑retardant treatment,
  • species of wood treated,
  • flame spread and smoke‑developed indices,
  • method of drying after treatment,
  • statement of conformance with the applicable FRTW standards, and
  • if exposed to weather or damp/wet locations, the ASTM D2898 rain‑test statement.
    These label content items are required by § 2303.2.5 and labeling procedures in § 1703.5 of the CBC .

Test methods and specimen configuration

  • Flame‑spread acceptance: test by ASTM E84 or UL 723 with listed flame spread index ≤ 25 and the extended‑duration flame front limit specified in § 2303.2 (and alternately by ASTM E2768 under § 2303.2.1) .
  • Wood structural panels: must be tested with a ripped or cut longitudinal gap of 1/8 in. (3.2 mm) per § 2303.2.4 .
  • Weathering/rain test: for materials to be used exposed to weather, the ASTM D2898 Standard Rain Test requirement and corresponding label wording apply (§ 2303.2.5) .

Manufacturer testing, published data and design adjustments

  • Manufacturers must determine the effects of treatment and redrying on lumber and panel design values using specified ASTM test methods (e.g., ASTM D5516 for plywood flexure; ASTM D5664 for lumber) and then publish allowable loads/spans or treatment adjustment factors for their products (§ 2303.2.6 and subsections) .
  • Design values for FRTW are subject to the same adjustments applicable to untreated wood and must be further adjusted to account for the treatment effects, temperatures and humidities anticipated in service (§ 2303.2.6) .

Permanence and method of labeling

Labels must be permanent (methods such as acid‑etching, laser etching, embossing, etc., as required by § 1703.5.4) and include the approved agency’s identification as required by § 1703.5.3 and § 2303.2.5 .

Decision‑relevant summary table

Decision dimension Required/Value Code reference
Flame‑spread limit for acceptance ≤ 25 (ASTM E84/UL 723) or alternate ASTM E2768 per § 2303.2.1 § 2303.2; § 2303.2.1
Panel test configuration Ripped/cut longitudinal gap = 1/8 in. (3.2 mm) § 2303.2.4
Required label items Agency mark; manufacturer; treatment name; species; flame‑spread & smoke indices; drying method; conformance; ASTM D2898 wording for weathered use § 2303.2.5; § 1703.5
Manufacturer technical data required Publish allowable loads/spans or treatment adjustment factors based on ASTM D5516, D6305, D5664, D6841, etc. § 2303.2.6; § 2303.2.6.1; § 2303.2.6.2
Moisture content before use Lumber ≤ 19%; wood structural panels ≤ 15% (KDAT limits described) § 2303.2.9
Label permanence/method Permanent marking (acid etched, laser, embossed, etc.) per § 1703.5.4 § 1703.5.4

Exceptions & special cases

  • Alternate fire test: manufacturers may use ASTM E2768 as an alternate test procedure per § 2303.2.1; where used, the alternate test must still achieve the flame spread limit and flame‑front limits in the code .
  • Weather‑exposed FRTW: panels or lumber intended for exterior or damp locations must include the ASTM D2898 wording on the label that there is “No increase in the listed classification when subjected to the Standard Rain Test” (§ 2303.2.5) .
  • Type I/II construction: special limitations on using FRTW in Type I and II construction are referenced in § 2303.2.10; consult that section for building‑type restrictions (§ 2303.2.10) .
  • Manufacturer publication: the CBC requires each manufacturer to publish allowable loads/spans or adjustment factors derived from the specified ASTM procedures; absence of published data means you cannot assume untreated design values apply (§ 2303.2.6.1–.2) .

Common mistakes

  • Accepting panels without the 1/8‑in. ripped/cut gap test configuration — the panel test specimen configuration is specified in § 2303.2.4 and is common cause of failed conformity reviews .
  • Using untreated plywood/lumber design values for FRTW without applying manufacturer‑published adjustment factors based on ASTM D5516/D5664 and ASTM D6305/D6841 procedures (§ 2303.2.6) .
  • Missing the required agency mark or non‑permanent labels — CBC requires permanent identification and an approved agency mark per § 2303.2.5 and § 1703.5.4 .
  • Assuming surface coatings or field applications of fire retardants suffice — the code prohibits relying on paints/coatings/stains as the required FRTW treatment method (§ 2303.2.3) .
  • Omitting the ASTM D2898 rain‑test statement on labels when material will be used in wet or exposed conditions (§ 2303.2.5) .

Worked example

Scenario: A manufacturer produces 3/4‑in. softwood plywood panels treated by pressure impregnation. Test outcomes: ASTM E84 flame‑spread = 20, smoke‑developed = 160. After treatment and kiln redrying the panels are 12% moisture content.

What is required to comply with the CBC?

  1. Fire test specimen: panels must have been tested with a ripped/cut longitudinal gap of 1/8 in. for the panel test per § 2303.2.4; verify the test report shows that configuration .
  2. Flame‑spread acceptance: with flame‑spread 20 (≤ 25) and flame‑front limits met, the panel satisfies the flame‑spread acceptance per § 2303.2 and alternates (if E2768 used) per § 2303.2.1 .
  3. Labeling: each panel must be permanently labeled with: approved agency mark, treating manufacturer name, treatment product name, species, flame‑spread 20 and smoke 160, drying method (e.g., kiln dried after treatment) and conformance statement; if these panels are for exterior exposure they must also include the ASTM D2898 rain‑test wording (§ 2303.2.5 and § 1703.5) .
  4. Published design data: the manufacturer must publish allowable maximum loads and spans for floor/roof sheathing for that treatment based on the ASTM D5516/D6305 process; the designer must use those published adjusted values (not the untreated plywood tables) in sizing and span checks (§ 2303.2.6.1) .
  5. Moisture content: panels are ≤ 15% moisture content before use (12% in this example), which satisfies § 2303.2.9 for wood structural panels .

If any of these items are missing from the label, test report, or manufacturer literature, the building official may require additional substantiating data or reject use until compliance is demonstrated (§ 1703.4.1) .

Related provisions (quick reference)

  • § 2303.2 — Fire‑retardant‑treated wood: general test acceptance language .
  • § 2303.2.1 — Alternate fire testing (ASTM E2768) .
  • § 2303.2.4 — Fire testing specimen configuration for wood structural panels (1/8 in. ripped gap) .
  • § 2303.2.5 — Labeling requirements for FRT lumber and panels (label content and ASTM D2898 wording) .
  • § 2303.2.6 and § 2303.2.6.1/.2 — Manufacturer test methods, adjustment factors and publication of allowable loads/spans (ASTM D5516, D6305, D5664, D6841) .
  • § 2303.2.9 — Moisture content requirements for lumber and wood structural panels before use (19% and 15% limits) .
  • § 1703.5 — Labeling procedures and permanence; § 1703.5.4 for acceptable permanent marking methods .
  • § 2303.2.3 — Surface coatings/paint are not an approved method of FRTW treatment .

Code references

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

  • CBC § 50.8 High relevance — show source text
    1. Wood floor assemblies using dimension lumber or structural composite lumber equal to or greater than 2-inch by 10-inch (50.8 mm by 254 mm) nominal dimension, or other approved floor assemblies demonstrating equivalent fire performance.
    2. Wood floor assemblies less than 600 square feet (55.7 m [2] ) within detached accessory structures with no habitable space above them.

    R302.14 Combustible insulation clearance. Combustible insulation shall be separated not less than 3 inches (76 mm) from recessed luminaires, fan motors and other heat-producing devices.

    Exception: Where heat-producing devices are listed for lesser clearances, combustible insulation complying with the listing requirements shall be separated in accordance with the conditions stipulated in the listing.

    Recessed luminaires installed in the building thermal envelope shall meet the requirements of the California Energy Code .

    R302.15 Fire-retardant-treated wood. Fire-retardant-treated wood (FRTW) is any wood product that, when impregnated with chemicals by a pressure process or other means during manufacture, shall have, when tested in accordance with ASTM E84 or UL 723, a listed flame spread index of 25 or less. In addition, the ASTM E84 or UL 723 test shall be continued for an additional 20-minute period and the flame front shall not progress more than 10.5 feet (3200 mm) beyond the center line of the burners at any time during the test.

    R302.15.1 Pressure process. For wood products impregnated with chemicals by a pressure process, the process shall be performed in closed vessels under pressures not less than 50 pounds per square inch gauge (psig) (344.7 kPa).

    R302.15.2 Other means during manufacture. For wood products impregnated with chemicals by other means during manufacture, the treatment shall be an integral part of the manufacturing process of the wood product. The treatment shall provide permanent protection to all surfaces of the wood product. The use of paints, coating, stains or other surface treatments is not an approved method of protection as required by this section.

    R302.15.3 Testing. For fire-retardant-treated wood products, the front and back faces of the wood product shall be tested in accordance with and produce the results required in Section R302.15.

    R302.15.3.1 Fire testing of fire-retardant-treated wood structural panels. Fire-retardant-treated wood structural panels shall be tested with a ripped or cut longitudinal gap of [1] / 8 inch (3.2 mm).

    302.15.4 Labeling. In addition to the labels required by Section R802.1.1 for sawn lumber and Section R803.2.1 for wood structural panels, each piece of fire-retardant-treated lumber and fire-retardant-treated wood structural panel shall be labeled. The label shall contain:

    1. The identification mark of an approved agency in accordance with Section 1703.5 of the California Building Code.

    2. Identification of the treating manufacturer.

    3. The name of the fire-retardant treatment.

    4. The species of wood treated.

    5. Flame spread index and smoke-developed index.

    6. Method of drying after treatment.

    7. Conformance to applicable standards in accordance with Sections R302.15.5 through R302.15.10.

    8. For FRTW exposed to weather, or a damp or wet location, the words “No increase in the listed classification when subjected to the Standard Rain Test” (ASTM D2898).

  • CBC § 15.3 High relevance — show source text

    R302.15.3 Testing. For fire-retardant-treated wood products, the front and back faces of the wood product shall be tested in accordance with and produce the results required in Section R302.15.

    R302.15.3.1 Fire testing of fire-retardant-treated wood structural panels. Fire-retardant-treated wood structural panels shall be tested with a ripped or cut longitudinal gap of [1] / 8 inch (3.2 mm).

    302.15.4 Labeling. In addition to the labels required by Section R802.1.1 for sawn lumber and Section R803.2.1 for wood structural panels, each piece of fire-retardant-treated lumber and fire-retardant-treated wood structural panel shall be labeled. The label shall contain:

    1. The identification mark of an approved agency in accordance with Section 1703.5 of the California Building Code.

    2. Identification of the treating manufacturer.

    3. The name of the fire-retardant treatment.

    4. The species of wood treated.

    5. Flame spread index and smoke-developed index.

    6. Method of drying after treatment.

    7. Conformance to applicable standards in accordance with Sections R302.15.5 through R302.15.10.

    8. For FRTW exposed to weather, or a damp or wet location, the words “No increase in the listed classification when subjected to the Standard Rain Test” (ASTM D2898).

    R302.15.5 Strength adjustments. Design values for untreated lumber and wood structural panels as specified in Section R802.1 shall be adjusted for fire-retardant-treated wood. Adjustments to design values shall be based on an approved method of investigation that takes into consideration the effects of the anticipated temperature and humidity to which the fire-retardant-treated wood will be subjected, the type of treatment and redrying procedures.

    R302.15.6 Fire-retardant-treated wood structural panels. The effect of treatment and the method of redrying after treatment, and exposure to high temperatures and high humidities on the flexure properties of fire-retardant-treated softwood plywood shall be determined in accordance with ASTM D5516. The test data developed by ASTM D5516 shall be used to develop adjustment factors, maximum loads and spans, or both for untreated plywood design values in accordance with ASTM D6305. Each manufacturer shall publish the allowable maximum loads and spans for service as floor and roof sheathing for their treatment.

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    R302.15.7 Fire-retardant-treated lumber. For each species of wood treated, the effect of the treatment and the method of redrying after treatment and exposure to high temperatures and high humidities on the allowable design properties of fire-retardant-treated lumber shall be determined in accordance with ASTM D5664. The test data developed by ASTM D5664 shall be used to develop modification factors for use at or near room temperature and at elevated temperatures and humidity in accordance with ASTM D6841. Each manufacturer shall publish the modification factors for service at temperatures of not less than 80°F (27°C) and for roof framing. The roof framing modification factors shall take into consideration the climatological location.

  • CBC § 2303.2.4 High relevance — show source text

    [BF] 2303.2.4 Fire testing of wood structural panels. Wood structural panels shall be tested with a ripped or cut longitudinal gap of [1] / 8 inch (3.2 mm).

    [BF] 2303.2.5 Labeling. In addition to the labels required in Section 2303.1.1 for sawn lumber and Section 2303.1.5 for wood structural panels, each piece of fire-retardant-treated lumber and wood structural panels shall be labeled. The label shall contain the following items:

    1. The identification mark of an approved agency in accordance with Section 1703.5.

    2. Identification of the treating manufacturer.

    3. The name of the fire-retardant treatment.

    4. The species of wood treated.

    5. Flame spread and smoke-developed index.

    6. Method of drying after treatment.

    7. Conformance with appropriate standards in accordance with Sections 2303.2.6 through 2303.2.9.

    8. For fire-retardant-treated wood exposed to weather, damp or wet locations, include the words “No increase in the listed classification when subjected to the Standard Rain Test” (ASTM D2898).

    2303.2.6 Design values. Design values for fire-retardant-treated wood, including connection design values, shall be subject to all adjustments applicable to untreated wood as specified in this chapter and shall be further adjusted to account for the effects of the fire-retardant treatment. Adjustments to design values for the effects of the fire-retardant treatment shall be based on an approved method of investigation that takes into consideration the anticipated temperature and humidity to which the fire-retardant-treated wood will be subjected, the type of treatment and redrying procedures. Adjustments to flexural design values for fire-retardant-treated plywood shall be determined in accordance with Section 2303.2.6.1. Adjustments to flexural, tension, compression and shear design values for fire-retardant-treated lumber shall be determined in accordance with Section 2303.2.6.2. Design values and treatment adjustment factors for fire-retardant-treated laminated veneer lumber shall be determined in accordance with Section 2303.2.6.3.

    2303.2.6.1 Fire-retardant-treated plywood. The effect of treatment and redrying after treatment, and any treatment-based effects due to exposure to high temperatures and high humidities on the flexure properties of fire-retardant-treated softwood plywood shall be determined in accordance with ASTM D5516. The test data developed in accordance with ASTM D5516 shall be used to develop treatment adjustment factors in accordance with ASTM D6305. Each manufacturer shall publish the allowable maximum loads and spans for service as floor and roof sheathing for its treatment based on the adjusted design values and taking into account the climatological location.

    2303.2.6.2 Fire-retardant-treated lumber. For each species of wood that is treated, the effect of treatment and redrying after treatment and any treatment-based effects due to exposure to high temperatures and high humidities on the allowable design properties of fire-retardant-treated lumber shall be determined in accordance with ASTM D5664. The test data developed in accordance with ASTM D5664 shall be used to develop treatment adjustment factors for use at or near room temperature and at elevated temperatures and humidity in accordance with ASTM D6841. Each manufacturer shall publish the treatment adjustment factors for service at maximum temperatures of not less than 80°F (27°C) and for roof framing. The roof framing modification factors shall take into consideration the climatological location.

  • CBC § 1703.4.1 High relevance — show source text

    1703.4.1 Research and investigation. Sufficient technical data shall be submitted to the building official to substantiate the proposed use of any product, material or assembly. If it is determined that the evidence submitted is satisfactory proof of performance for the use intended, the building official shall approve the use of the product, material or assembly subject to the requirements of this code. The costs, reports and investigations required under these provisions shall be paid by the owner or the owner’s authorized agent.

    1703.4.2 Research reports. Supporting data, where necessary to assist in the approval of products, materials or assemblies not specifically provided for in this code, shall consist of valid research reports from approved sources.

    1703.5 Labeling. Products, materials or assemblies required to be labeled shall be labeled in accordance with the procedures set forth in Sections 1703.5.1 through 1703.5.4.

    1703.5.1 Testing. An approved agency shall test a representative sample of the product, material or assembly being labeled to the relevant standard or standards. The approved agency shall maintain a record of the tests performed. The record shall provide sufficient detail to verify compliance with the test standard.

    1703.5.2 Inspection and identification. The approved agency shall periodically perform an inspection, which shall be in-plant if necessary, of the product or material that is to be labeled. The inspection shall verify that the labeled product, material or assembly is representative of the product, material or assembly tested.

    1703.5.3 Label information. The label shall contain the manufacturer’s identification, model number, serial number or definitive information describing the performance characteristics of the product, material or assembly and the approved agency’s identification.

    1703.5.4 Method of labeling. Information required to be permanently identified on the product, material or assembly shall be acid etched, sand blasted, ceramic fired, laser etched, embossed or of a type that, once applied, cannot be removed without being destroyed.

    1703.6 Evaluation and follow-up inspection services. Where structural components or other items regulated by this code are not visible for inspection after completion of a prefabricated assembly, the owner or the owner’s authorized agent shall submit a report of each prefabricated assembly. The report shall indicate the complete details of the assembly, including a description of the assembly and its components, the basis upon which the assembly is being evaluated, test results and similar information and other data as necessary for the building official to determine conformance to this code. Such a report shall be approved by the building official.

    1703.6.1 Follow-up inspection. The owner or the owner’s authorized agent shall provide for special inspections of fabricated items in accordance with Section 1704.2.5.

    1703.6.2 Test and inspection records. Copies of necessary test and special inspection records shall be filed with the building official.

    SECTION 1704—SPECIAL INSPECTIONS AND TESTS, CONTRACTOR RESPONSIBILITY AND STRUCTURAL OBSERVATION

    1704.1 General. Special inspections and tests, statements of special inspections, responsibilities of contractors, submittals to the building official and structural observations shall meet the applicable requirements of this section.

  • CBC § 4.1 High relevance — show source text

    [OSHPD 1 & 4] Tests performed by an independent approved testing agency/laboratory or under the responsible charge of a compe- tent approved independent Registered Design Professional shall be deemed to comply with requirements of this section. Test reports for structural tests shall be reviewed and accepted by an independent California licensed structural engineer.

    1703 A .4.1 Research and investigation. Sufficient technical data shall be submitted to the building official to substantiate the proposed use of any product, material or assembly. If it is determined that the evidence submitted is satisfactory proof of performance for the use intended, the building official shall approve the use of the product, material or assembly subject to the requirements of this code. The costs, reports and investigations required under these provisions shall be paid by the owner or the owner’s authorized agent.

    1703 A .4.2 Research reports. Supporting data, where necessary to assist in the approval of products, materials or assemblies not specifically provided for in this code, shall consist of valid research reports from approved sources.

    1703 A .5 Labeling. Products, materials or assemblies required to be labeled shall be labeled in accordance with the procedures set forth in Sections 1703 A .5.1 through 1703 A .5.4.

    1703 A .5.1 Testing. An approved agency shall test a representative sample of the product, material or assembly being labeled to the relevant standard or standards. The approved agency shall maintain a record of the tests performed. The record shall provide sufficient detail to verify compliance with the test standard.

    1703 A .5.2 Inspection and identification. The approved agency shall periodically perform an inspection, which shall be in-plant if necessary, of the product or material that is to be labeled. The inspection shall verify that the labeled product, material or assembly is representative of the product, material or assembly tested.

    1703 A .5.3 Label information. The label shall contain the manufacturer’s identification, model number, serial number or definitive information describing the performance characteristics of the product, material or assembly and the approved agency’s identification.

    1703 A .5.4 Method of labeling. Information required to be permanently identified on the product, material or assembly shall be acid etched, sand blasted, ceramic fired, laser etched, embossed or of a type that, once applied, cannot be removed without being destroyed.

    1703 A .6 Evaluation and follow-up inspection services. Where structural components or other items regulated by this code are not visible for inspection after completion of a prefabricated assembly, the owner or the owner’s authorized agent shall submit a report of each prefabricated assembly. The report shall indicate the complete details of the assembly, including a description of the assembly and its components, the basis upon which the assembly is being evaluated, test results and similar information and other data as necessary for the building official to determine conformance to this code. Such a report shall be approved by the building official.

    1703 A .6.1 Follow-up inspection. The owner or the owner’s authorized agent shall provide for special inspections of fabricated items in accordance with Section 1704 A .2.5.

    1703 A .6.2 Test and inspection records. Copies of necessary test and special inspection records shall be filed with the building official.

  • CBC § 2303.2 High relevance — show source text

    [BF] 2303.2 Fire-retardant-treated wood. Fire-retardant-treated wood is any wood product that, when impregnated with chemicals by a pressure process or other means during manufacture, shall have, when tested in accordance with ASTM E84 or UL 723, a listed flame spread index of 25 or less. The ASTM E84 or UL 723 test shall be continued for an additional 20-minute period and the flame front shall not progress more than 10.5 feet (3200 mm) beyond the centerline of the burners at any time during the test.

    [BF] 2303.2.1 Alternate fire testing. Fire-retardant-treated wood is also any wood product that, when impregnated with chemicals by a pressure process or other means during manufacture, shall have, when tested in accordance with ASTM E2768, a listed flame spread index of 25 or less and where the flame front does not progress more than 10.5 feet (3200 mm) beyond the centerline of the burners at any time during the test.

    [BF] 2303.2.2 Pressure process. For wood products impregnated with chemicals by a pressure process, the process shall be performed in closed vessels under pressures not less than 50 pounds per square inch gauge (psig) (345 kPa).

    [BF] 2303.2.3 Other means during manufacture. For wood products impregnated with chemicals by other means during manufacture, the treatment shall be an integral part of the manufacturing process of the wood product. The treatment shall provide permanent protection to all surfaces of the wood product. The use of paints, coating, stains or other surface treatments is not an approved method of protection as required in this section.

    [BF] 2303.2.4 Fire testing of wood structural panels. Wood structural panels shall be tested with a ripped or cut longitudinal gap of [1] / 8 inch (3.2 mm).

    [BF] 2303.2.5 Labeling. In addition to the labels required in Section 2303.1.1 for sawn lumber and Section 2303.1.5 for wood structural panels, each piece of fire-retardant-treated lumber and wood structural panels shall be labeled. The label shall contain the following items:

    1. The identification mark of an approved agency in accordance with Section 1703.5.

    2. Identification of the treating manufacturer.

    3. The name of the fire-retardant treatment.

    4. The species of wood treated.

    5. Flame spread and smoke-developed index.

    6. Method of drying after treatment.

    7. Conformance with appropriate standards in accordance with Sections 2303.2.6 through 2303.2.9.

    8. For fire-retardant-treated wood exposed to weather, damp or wet locations, include the words “No increase in the listed classification when subjected to the Standard Rain Test” (ASTM D2898).

    2303.2.6 Design values. Design values for fire-retardant-treated wood, including connection design values, shall be subject to all adjustments applicable to untreated wood as specified in this chapter and shall be further adjusted to account for the effects of the fire-retardant treatment. Adjustments to design values for the effects of the fire-retardant treatment shall be based on an approved method of investigation that takes into consideration the anticipated temperature and humidity to which the fire-retardant-treated wood will be subjected, the type of treatment and redrying procedures.

  • CBC § 3.1 Medium relevance — show source text

    Design wind loads for exterior glazing not part of a labeled assembly shall be permitted to be determined in accordance with Chapter 24 of the California Building Code .

    R609.3 Testing and labeling. ANSI WMA 100Exterior windows and sliding doors shall be tested by an approved independent laboratory, and bear a label identifying manufacturer, performance characteristics and approved inspection agency to indicate compliance with AAMA/WDMA/CSA 101/I.S.2/A440. Exterior side-hinged doors shall be tested and labeled as conforming to AAMA/WDMA/CSA 101/I.S.2/A440 or ANSI WMA 100, or comply with Section R609.5.

    Exception: Decorative glazed openings.

    R609.3.1 Comparative analysis. Structural wind load design pressures for window and door units different than the size tested in accordance with Section R609.3 shall be permitted to be different than the design value of the tested unit where determined in accordance with one of the following comparative analysis methods:

    1. Structural wind load design pressures for window and door units smaller than the size tested in accordance with Section R609.3 shall be permitted to be higher than the design value of the tested unit provided such higher pressures are determined by accepted engineering analysis. Components of the smaller unit shall be the same as those of the tested unit. Where such calculated design pressures are used, they shall be validated by an additional test of the window or door unit having the highest allowable design pressure.

    2. In accordance with WDMA I.S.11.

    R609.4 Garage doors. Garage doors shall be tested in accordance with either ASTM E330 or ANSI/DASMA 108, and shall meet the pass/fail criteria of ANSI/DASMA 108.

    R609.4.1 Garage door labeling. Garage doors shall be labeled with a permanent label provided by the garage door manufacturer. The label shall identify the garage door manufacturer, the garage door model/series number, the positive and negative design wind pressure rating, the installation instruction drawing reference number, and the applicable test standard. Garage doors shall be installed in accordance with the manufacturer’s installation instructions.

    R609.5 Other exterior window and door assemblies. Exterior windows and door assemblies not included within the scope of Section R609.3 or R609.4 shall be tested in accordance with ASTM E330. Glass in assemblies covered by this section shall comply with Section R324.5.

    R609.6 Windborne debris protection. Protection of exterior windows, glass doors and doors with glass in buildings located in windborne debris regions shall be in accordance with Section R301.2.1.2.

    R609.6.1 Fenestration testing and labeling. Fenestration shall be tested by an approved independent laboratory, listed by an approved entity, and bear a label identifying the manufacturer, performance characteristics and an approved inspection agency to indicate compliance with the requirements of the following specification(s):

    1. ASTM E1886 and ASTM E1996; or

    2. AAMA 506.

    R609.6.2 Impact protective systems testing and labeling. Impact protective systems shall be tested for impact resistance by an approved independent laboratory for compliance with ASTM E1886 and ASTM E1996. Impact protective systems shall be tested

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  • CBC § 1114.2 Medium relevance — show source text

    (2) Lithium bromide absorption system using water as the refrigerant.

    1114.2 Design Requirements. Flaring devices shall be designed to incinerate the entire discharge. The products of refrigerant incineration shall not pose health or environmental hazards. Incineration shall be automatic upon initiation of discharge, shall be designed to prevent blow-back, and shall not expose structures or materials to the threat of fire. Standby fuel, such as LP-Gas, and standby power shall have the capacity to operate for one and a half times the required time for complete incineration of the charge.

    1114.3 Testing. Flaring systems shall be tested to demonstrate their safety and effectiveness. A report from an approved agency shall be submitted detailing the emission products from the system as installed.

    1115.0 Labeling and Identification.

    1115.1 General. In addition to labels required elsewhere in this chapter, a refrigeration system shall be provided with identification labels in accordance with Section 1115.2

    through Section 1115.5.

    1115.2 Volume and Type. A condenser, receiver, absorber, accumulator and similar equipment having an internal volume of more than 3 cubic feet (0.1 m [3] ) and containing refrigerant shall be equipped with a permanent label setting forth the type of refrigerant in such vessel.

    1115.3 Permanent Sign. In a refrigeration machinery room and for a direct refrigerating system of more than 10 horsepower (7.5 kW), there shall be a permanent sign at an approved location giving the following information:

    (1) Name of contractor installing the equipment.

    (2) Name and number designation of refrigerant in system.

    (3) Pounds of refrigerant in system.

    1115.4 Marking of Pressure-Relief Devices. Pressurerelief valves for refrigerant containing components shall be set and sealed by the manufacturer or an assembler as defined in ASME BPVC Section VIII.1. Each pressure relief valve shall be marked by the manufacturer or assembler with the data required in ASME BPVC Section VIII.1.

    Exception: Relief valves for systems with design pressures of 15 pounds-force per square inch gauge (psig) (103 kPa gauge) or less shall be marked by the manufacturer with the pressure setting capacity. [ASHRAE 15:9.6.1]

    1115.4.1 Rupture Members. Rupture members for refrigerant pressure vessels shall be marked with the data required in accordance with ASME BPVC Section VIII.1. [ASHRAE 15:9.6.2]

    1115.4.2 Fusible Plugs. Fusible plugs shall be marked with the melting temperatures in °F (°C).

    [ASHRAE 15:9.6.3]

    1115.5 Nameplate. Each self-contained system and each separate condensing unit, compressor, or compressor unit sold for field assembly in a refrigerating system shall carry a nameplate marked with the manufacturer’s name, nationally registered trademark or trade name, identification num

    2025 CALIFORNIA MECHANICAL CODE 245

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

    REFRIGERATION

  • CBC § 716.2.9.1.1 Medium relevance — show source text

    716.2.9.1.1 Light kits, louvers and components. Listed light kits and louvers and their required preparations shall be considered as part of the labeled door where such installations are done under the listing program of the third-party agency. Fire doors and fire door assemblies shall be permitted to consist of components, including glazing, vision light kits and hardware that are listed or classified and labeled for such use by different third-party agencies.

    716.2.9.2 Oversized doors. Oversized fire doors shall bear an oversized fire door label by an approved agency or shall be provided with a certificate of inspection furnished by an approved testing agency. Where a certificate of inspection is furnished by an approved testing agency, the certificate shall state that the door conforms to the requirements of design, materials and construction, but has not been subjected to the fire test.

    716.2.9.3 Smoke and draft control door labeling requirements. Smoke and draft control doors complying with UL 1784 shall be labeled in accordance with Section 716.2.9.1 and shall show the letter “S” on the fire-rating label of the door. This marking shall indicate that the door and frame assembly are in compliance where listed or labeled gasketing is installed.

    716.2.9.4 Fire door frame labeling requirements. Fire door frames shall be labeled showing the names of the manufacturer and the third-party inspection agency.

    Exception: In Group I-3 doors that are required to be 45 minutes or higher shall be fire-rated assemblies or certified by the manu- facturer as being equivalent to the required standard.

    716.2.9.5 Labeling. Fire-rated glazing shall bear a label or other identification showing the name of the manufacturer, the test standard and information required in Table 716.1(1) that shall be issued by an approved agency and shall be permanently identified on the glazing.

    716.2.9.6 Fire door operator labeling requirements. Fire door operators for horizontal sliding doors shall be labeled and listed for use with the assembly.

    716.2.10 Installation of door assemblies in corridors and smoke barriers. Installation of smoke doors shall be in accordance

    with NFPA 105.

    716.3 Fire window assemblies. Fire window assemblies required by other sections of this code shall comply with the provisions of this section.

    716.3.1 Testing requirements. Fire window assemblies shall be constructed of any material or assembly of component materials that conforms to the test requirements of Sections 716.3.1.1 and 716.3.1.2 and the fire protection rating indicated in Table 716.1(3).

    716.3.1.1 Testing under positive pressure. NFPA 257 or UL 9 shall evaluate fire-protection-rated glazing under positive pressure. Within the first 10 minutes of a test, the pressure in the furnace shall be adjusted so not less than two-thirds of the test specimen is above the neutral pressure plane, and the neutral pressure plane shall be maintained at that height for the balance of the test.

    716.3.1.2 Nonsymmetrical glazing systems. Nonsymmetrical fire-protection-rated glazing systems in fire partitions, fire barriers or in exterior walls with a fire separation distance of 10 feet (3048 mm) or less pursuant to Section 705 shall be tested with both faces exposed to the furnace, and the assigned fire protection rating shall be the shortest duration obtained from the two tests conducted in compliance with NFPA 257 or UL 9.

  • CBC § 1709.5.1 Medium relevance — show source text

    1709.5.1 Exterior windows and doors. Exterior windows and sliding doors shall be tested and labeled as conforming to AAMA/WDMA/CSA101/I.S.2/A440. The label shall state the name of the manufacturer, the approved labeling agency and the product designation as specified in AAMA/WDMA/CSA101/I.S.2/A440. Exterior side-hinged doors shall be tested and labeled as conforming to AAMA/WDMA/CSA101/I.S.2/A440 or comply with Section 1709.5.2. Products tested and labeled as conforming to AAMA/WDMA/CSA 101/I.S.2/A440 shall not be subject to the requirements of Sections 2403.2 and 2403.3.

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    SPECIAL INSPECTIONS AND TESTS

    1709.5.2 Exterior windows and door assemblies not provided for in Section 1709.5.1. Exterior window and door assemblies shall be tested in accordance with ASTM E330. Exterior window and door assemblies containing glass shall comply with Section 2403. The design pressure for testing shall be calculated in accordance with Chapter 16. Each assembly shall be tested for 10 seconds at a load equal to 1.5 times the design pressure.

    1709.5.2.1 Garage doors and rolling doors. Garage doors and rolling doors shall be tested in accordance with either ASTM E330 or ANSI/DASMA 108, and shall meet the pass/fail criteria of ANSI/DASMA 108. Garage doors and rolling doors shall be labeled with a permanent label identifying the door manufacturer, the door model/series number, the positive and negative design wind pressure rating, the installation instruction drawing reference number, and the applicable test standard.

    1709.5.3 Windborne debris protection. Protection of exterior glazed openings in buildings located in windborne debris regions shall be in accordance with Section 1609.2.

    1709.5.3.1 Impact protective systems testing and labeling. Impact protective systems shall be tested for impact resistance by an approved independent laboratory for compliance with ASTM E1886 and ASTM E1996 and for design wind pressure for compliance with ASTM E330. Required design wind pressures shall be determined in accordance with ASCE 7, and for the purposes of this section, multiplied by 0.6 to convert to allowable stress design.

    Impact protective systems shall have a permanent label applied in accordance with Section 1703.5.4, identifying the manufacturer, product designation, performance characteristics, and approved inspection agency.

    1709.6 Skylights and sloped glazing. Skylights and sloped glazing shall comply with the requirements of Chapter 24.

    1709.7 Test specimens. Test specimens and construction shall be representative of the materials, workmanship and details normally used in practice. The properties of the materials used to construct the test assembly shall be determined on the basis of tests on samples taken from the load assembly or on representative samples of the materials used to construct the load test assembly. Required tests shall be conducted or witnessed by an approved agency.

    SECTION 1710—OFF-SITE CONSTRUCTION [OSHPD 1R, 2 & 5]

    1710.1 General. This section applies to off-site construction and shall govern the requirements for planning, design, fabrication, assem- bly, inspection and regulatory compliance.

  • CBC § 2.95 Medium relevance — show source text

    00|2.95|2.20|1.45|3.00|2.35|1.25|DR| |Cold-formed steel framing
    (minimum penetration of steel
    thickness plus 3 threads)|#8 screw into 33 mil steel or
    thicker|8|3.00|2.55|1.60|0.60|3.00|1.80|DR|DR| |Cold-formed steel framing
    (minimum penetration of steel
    thickness plus 3 threads)|#8 screw into 33 mil steel or
    thicker|12|3.00|1.80|DR|DR|3.00|0.65|DR|DR| |Cold-formed steel framing
    (minimum penetration of steel
    thickness plus 3 threads)|#10 screw into 33 mil steel|6|4.00|3.50|2.70|1.95|4.00|2.90|1.70|0.55| |Cold-formed steel framing
    (minimum penetration of steel
    thickness plus 3 threads)|#10 screw into 33 mil steel|8|4.00|3.10|2.05|1.00|4.00|2.25|0.70|DR| |Cold-formed steel framing
    (minimum penetration of steel
    thickness plus 3 threads)|#10 screw into 33 mil steel|12|4.00|2.25|0.70|DR|3.70|1.05|DR|DR| |Cold-formed steel framing
    (minimum penetration of steel
    thickness plus 3 threads)|#10 screw into 43 mil steel or
    thicker|6|4.00|4.00|4.00|3.60|4.00|4.00|3.45|2.70| |Cold-formed steel framing
    (minimum penetration of steel
    thickness plus 3 threads)|#10 screw into 43 mil steel or
    thicker|8|4.00|4.00|3.70|3.00|4.00|3.85|2.80|1.80| |Cold-formed steel framing
    (minimum penetration of steel
    thickness plus 3 threads)|#10 screw into 43 mil steel or
    thicker|12|4.00|3.85|2.80|1.80|4.00|3.05|1.50|DR| |For SI: 1 inch = 25.4 mm, 1 pound per square foot (psf) = 0.0479 kPa, 1 pound per square inch = 0.00689 MPa.
    DR = design required, o.c. = on center.
    a. Cold-formed steel framing shall be minimum 33 ksi steel for 33 mil and 43 mil steel and 50 ksi steel for 54 mil steel or thicker.
    b. Screws shall comply with the requirements of AISI S240.
    c. Foam sheathing shall have a minimum compressive strength of 15 pounds per square inch in accordance with ASTM C578 or ASTM C1289.|For SI: 1 inch = 25.4 mm, 1 pound per square foot (psf) = 0.0479 kPa, 1 pound per square inch = 0.00689 MPa.
    DR = design required, o.c. = on center.
    a. Cold-formed steel framing shall be minimum 33 ksi steel for 33 mil and 43 mil steel and 50 ksi steel for 54 mil steel or thicker.
    b.

  • CBC § 517.34. Medium relevance — show source text

    12. Transformers.

    13. Electrical substations.

    14. UPS and batteries.

    15. Panelboards as defined in the California Electrical Code (CEC) Article 100. 16. Industrial control panels as defined in the California Electrical Code (CEC) Article 100. 17. Power isolation and correction systems. 18. Motorized surgical lighting systems. 19. Motorized operating table systems. 20. Internal communication servers, routers and switches failure of which could impair the continued operation of the facility. 21. Medical gas and vacuum systems. 22. Electrical busways as defined in UL 857. 23. Electrical control panels powered by the life safety branch in accordance with the California Electrical Code (CEC) Article 517.33 or the critical branch in accordance with the California Electrical Code (CEC) Article 517.34.

    Exceptions: 1. Equipment and components weighing not more than 75 lbs. rigidly attached to structures or surface mounted on equipment or components that are not required to have special seismic certification by this section. 2. Mobile equipment/components. 3. Pipes, ducts, conduits and cable trays, excluding in-line equipment and components. 4. Underground tanks. 5. Electric motors, base-mounted horizontal pumps and compressors. 6. Based-mounted vertical pumps up to 20 hp. 7. Substitution of certified active subcomponents up to operating weight of 10 lbs. 8. Components where importance factor, I p , is permitted to be 1.0 by this code. 9. Emergency generators up to 25 kilowatts. 10. Equipment and components used for clinical trials only. 11. Elevator machines and governors. 12. Temporary and Interim equipment.

    For Exceptions 5, 6 and 7:

    Exempt subcomponents, which are an integral part of equipment that require special seismic certification, shall be tested attached to the equipment. Exempt subcomponents shall be permitted to be substituted without testing, provided that the substituted subcomponent relative to the certified subcomponent has: 1. Similar configuration with equivalent function. 2. Supports and attachments of similar configuration with equivalent strength and stiffness.

    3. Same attachment location.

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    �

    �

    SPECIAL INSPECTIONS AND TESTS

    4. Changes in dimensions, center of gravity and mass, of not more than 10 percent of the certified subcomponent and still meets Exception 5, 6 or 7. 5. Manufacturing process with ISO 9001 certification.

    1705 A .14.4 Seismic isolation and damping systems. Seismic isolation and damping systems in structures assigned to Seismic Design Category D, E or F shall be tested in accordance with Section 17.8 and 18.6 of ASCE 7.

    Prototype and production testing and associated acceptance criteria for isolator units and damping devices shall be subject to preapproval by the building official. Testing exemption for similar units shall require approval by the building official.

Frequently asked questions

Who must apply the label — manufacturer or supplier?

The treating manufacturer (or the entity responsible for the treatment) must ensure each piece is permanently labeled with the required information per § 2303.2.5 and § 1703.5 .

Is the ripped/cut gap test requirement optional for panels?

No — wood structural panels used in fire testing must be tested with a ripped or cut longitudinal gap of 1/8 in. as specified in § 2303.2.4 .

Can field‑applied fire retardants meet the code?

No — the code does not accept paints, coatings, stains or other surface treatments as the required FRTW treatment; the treatment must be integral as described in § 2303.2.3 .

If a panel’s flame spread is ≤ 25 but the manufacturer hasn’t published spans, can I size it like untreated plywood?

No — the CBC requires manufacturers to publish allowable loads/spans or treatment adjustment factors derived from the ASTM test procedures; designers must use those published values, not the untreated tables (§ 2303.2.6.1) .

What label wording is required for exterior (weather‑exposed) FRTW?

If the material is for weather‑exposed, damp or wet locations, the label must include “No increase in the listed classification when subjected to the Standard Rain Test (ASTM D2898)” as required in § 2303.2.5 .

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California Building Code