CBC · California Building Code

High‑hazard Group H — classification criteria and tables

Group H in the CBC is triggered when hazardous materials are present in a control area in amounts larger than the maximums listed in Table 307.1(1); use the table (and its sprinkler/cabinet/outdoor footnotes) together with the control‑area rules in § 414 and the Group definitions in § 307.4 to determine whether a space must be treated as H‑1 through H‑5.

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Last reviewed: July 5, 2026

What the code requires — 2-4 sentences

High‑hazard Group H applies where the manufacture, processing, generation or storage of materials creates a physical or health hazard in quantities greater than the maximum allowed in control areas (so the presence of those excess quantities triggers Group H classification). The threshold quantities for physical hazards are set in Table 307.1(1) and are used together with the control‑area rules in Section 414; the Group definitions (H‑1 through H‑5) and the H‑2 description are in Sections 307.1 and 307.4 of the CBC. See § 307.1 and Table 307.1(1) for the quantitative thresholds and § 307.4 for H‑2 material types.

Requirements in detail

Basic rule and how to use the table

Step 1: Identify the hazardous material and its hazard class (physical‑hazard categories follow the Fire Code references used in the CBC).
Step 2: Find that material in Table 307.1(1) to read the maximum allowable quantity per control area for the relevant storage or use condition. If the actual quantity in any control area exceeds the Table value, the space must be treated as a Group H occupancy (or the occupancy is recategorized to the Group indicated in the table). This is the mechanism described in § 307.1.
Control areas and how they interact: control areas are the unit used to measure the “maximum allowable quantity” — control areas must meet the construction and separation rules in § 414 (fire barriers/horizontal assemblies, separation, percentage limits per floor, etc.). See § 414 for control‑area construction and reporting requirements.

Key numeric thresholds (decision‑relevant excerpts from Table 307.1(1))

Use this short decision table when evaluating whether storage/use quantities trigger Group H. (This is a selection — the full Table 307.1(1) contains many more materials and rows; always check the full table for the exact material and condition.)

Material	Hazard class / condition	Max allowable per control area (storage, liquid gallons unless noted)	Group when exceeded	Code reference
Combustible liquid — Class II	storage (liquid)	120 gallons (per control area)	H‑2 or H‑3	Table 307.1(1); see § 307.1
Combustible liquid — Class IIIA	storage (liquid)	330 gallons (per control area)	H‑2 or H‑3	Table 307.1(1); see § 307.1
Combustible liquid — Class IIIB	storage (liquid)	Not limited in table (no finite control‑area limit)	Not H under this entry	Table 307.1(1)

Notes to table:

The table includes different columns for storage (solid, liquid, gas) and for use in closed vs open systems; use the correct column for your operation. See the full Table 307.1(1) for those distinctions.
Table footnotes allow certain increases to the maximum allowable quantities (for example: automatic sprinkler protection, approved storage cabinets, outdoor control areas). These adjustments are specified in the table notes — e.g., maximum allowable quantities shall be increased 100% in buildings sprinklered per the referenced sprinkler section and may be similarly increased for approved cabinets or outdoor areas. Apply notes cumulatively where both apply.

Group definitions that control classification

§ 307.1: A space becomes Group H when hazardous materials are present “in quantities in excess of those allowed in control areas” per Tables 307.1(1) and 307.1(2). The Group H categories are H‑1 through H‑5 and must comply with Section 415 and the California Fire Code.
§ 307.4: H‑2 is the Group for materials that pose a deflagration hazard or accelerated burning (examples listed in § 307.4 include Class I/II/IIIA flammable or combustible liquids in normally open containers/systems, combustible dusts under certain conditions, flammable gases of specified categories, cryogenic flammable fluids, certain oxidizers and organic peroxides, pyrophorics nondetonable, etc.). Use § 307.4 to determine whether the material type itself falls within the H‑2 list.

Reporting and documentation

A report is required identifying expected maximum quantities for storage, closed‑system use and open‑system use and must subdivide materials per Tables 307.1(1) and 307.1(2). The report must state the proposed protection (control areas, fire protection systems, Group H classification) and be prepared by a qualified person acceptable to the building official (see § 414.1.3).

Exceptions & special cases

Table notes: the maximum allowable quantity per control area can be increased by 100% where the building is sprinklered per the applicable sprinkler standard, and also by 100% where materials are stored inside approved storage cabinets; when both apply the increases are cumulative — read the table notes carefully.
Outdoor control areas: the table notes allow increased maximum quantities for outdoor control areas (see the table notes).
Some materials and operations are handled elsewhere: Group H thresholds are coordinated with the California Fire Code; quantities counted under specific Fire Code allowances (for example certain retail or laboratory uses) may be exempted from contributing to Group H classification — consult the Fire Code cross references and § 307.1 and the Fire Code occupancy exemptions.

If a material or exact condition you have is not clearly listed in Table 307.1(1) in the uploaded excerpt, you must consult the full table in the CBC (or the California Fire Code cross references) — do not infer limits. The uploaded excerpts include portions of Table 307.1(1) but not every single row and footnote; check the published table in the code for the complete set of materials and notes.

Common mistakes

Using gross floor‑area quantities instead of per‑control‑area quantities — the Table limits are per control area (not per building unless the control area equals the whole building). See Table 307.1(1) and § 414 for control‑area rules.
Ignoring table footnotes (sprinkler/cabinet/outdoor increases) — failing to apply permitted increases or misapplying them is a frequent source of errors. Read the table notes and apply increases only where the specific note criteria are met.
Misclassifying the hazard class of a material (e.g., treating a combustible liquid as Class IIIB when the Fire Code classification is different for that product); classification must follow the hazard categories referenced in the Fire Code — the CBC table relies on those hazard categories.
Forgetting the required hazardous‑materials report and qualified preparer requirement under § 414.1.3.

Worked example — concrete scenario

Scenario: a tenant plans to store 200 gallons of a Class II combustible liquid in a single enclosed workroom (one control area) inside a building that is not sprinklered.

Find the Table entry for “Combustible liquid — Class II” (storage, liquid): Table 307.1(1) lists 120 gallons per control area for Class II storage.
Compare actual quantity to the limit: 200 gallons > 120 gallons, so the quantity in that control area exceeds the table limit. Under § 307.1 that triggers High‑hazard Group H classification for that area (the table identifies the Group when exceeded as H‑2 or H‑3 depending on the material; Class II storage is in the row that references H‑2 or H‑3).
Interpretation: because Class II combustible liquids are listed as H‑2 (materials that pose deflagration/accelerated burning hazard — see § 307.4), this control area would require treatment as Group H‑2 (and must comply with Section 415 and the California Fire Code requirements for H‑2). See § 307.4 for the kinds of materials that fall in H‑2.
Options to avoid a Group H classification for the tenant’s room would include (a) reduce the stored liquid to ≤ 120 gallons per control area, (b) move quantities into additional, properly separated control areas so each stays within the table limit, or (c) apply an allowed increase (for example, if the building were sprinklered and other table‑note criteria applied, the allowable quantity could increase per the table notes) — but those options must be implemented in accordance with the CBC table notes and § 414 control‑area construction rules.

Related provisions (quick list)

§ 307.1 — High‑hazard Group H scope and mechanism (Table thresholds trigger Group H).
Table 307.1(1) — Maximum allowable quantity per control area for hazardous materials posing a physical hazard (primary quantitative tool).
§ 307.4 — Definition and examples for Group H‑2 (materials that pose deflagration/accelerated burning hazard).
§ 414 (Sections 414.1–414.2, 414.2.1, 414.1.3) — Control‑area construction, reporting, and separation rules (how to implement control areas referenced by Table 307.1(1)).
§ 415 — Special Group H requirements (fire detection, automatic sprinklers, alarms, separation and material‑specific requirements).
§ 903.2.5 (and related sprinkler sections) — sprinkler requirements that interact with Table 307.1(1) footnotes (sprinklered buildings may receive allowed increases).
California Fire Code (ch. 50–67 / quantity limits) — cross referenced for hazard categories and occupancy exemptions that affect how quantities are counted toward Group H.

Code references

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

CBC § 3-6 High relevance — show source text

Furniture

Hemp products

Jute products

Laundries

Leather products

Lithium-ion batteries

Machinery

Metals

Millwork (sash and door)

[SFM] Motion picture and television production studio Sound Stages, Approved Production Facilities and production locations (with- out live audiences)

Motion pictures and television filming (without spectators)

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OCCUPANCY CLASSIFICATION AND USE

Musical instruments

Optical goods

Paper mills or products

Photographic film

Plastic products

Printing or publishing

Recreational vehicles

Refuse incineration

Shoes

Soaps and detergents

Textiles

Tobacco

Trailers

Upholstering

Vehicles powered by lithium-ion or lithium metal batteries

Water/sewer treatment facilities

Wood; distillation

Woodworking (cabinet)

306.2.1 Aircraft manufacturing facilities. Aircraft manufacturing facilities shall comply with Section 412.6.

306.3 Low-hazard factory industrial, Group F-2. Factory industrial uses that involve the fabrication or manufacturing of noncombustible materials that during finishing, packing or processing do not involve a significant fire hazard shall be classified as Group F-2 occupancies and shall include, but not be limited to, the following:

Beverages: up to and including 20-percent alcohol content

Brick and masonry

Ceramic products

Foundries

Glass products

Gypsum

Ice

Metal products (fabrication and assembly)

SECTION 307—HIGH-HAZARD GROUP H

[F] 307.1 High-hazard Group H. High-hazard Group H occupancy includes, among others, the use of a building or structure, or a portion thereof, that involves the manufacturing, processing, generation or storage of materials that constitute a physical or health hazard in quantities in excess of those allowed in control areas complying with Section 414, based on the maximum allowable quantity limits for control areas set forth in Tables 307.1(1) and 307.1(2). Hazardous occupancies are classified in Groups H-1, H-2, H-3, H-4 and H-5 and shall be in accordance with this section, the requirements of Section 415 and the California Fire Code . Hazardous materials stored or used on top of roofs or canopies shall be classified as rooftop storage or use and shall comply with the California Fire Code .

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OCCUPANCY CLASSIFICATION AND USE

[F] TABLE 307.1(1)—MAXIMUM ALLOWABLE QUANTITY PER CONTROL AREA OF HAZARDOUS MATERIALS POSING A PHYSICAL HAZARDa, i, l, m	Col2	Col3	Col4	Col5	Col6	Col7	Col8	Col9	Col10	Col11
MATERIAL	CLASS	GROUP WHEN THE MAXIMUM ALLOWABLE QUANTITY IS EXCEEDED	STORAGEb	STORAGEb	STORAGEb	**USE-CLOSED

CBC § 203.6.1. High relevance — show source text
Hazardous occupancies are classified in Groups H-1, H-2, H-3, H-4 and H-5 and shall be in accordance with this code and the requirements of Section 415 of the California Building Code . Hazardous materials stored or used on top of roofs or canopies shall be classified as rooftop storage or use and shall comply with this code.

203.6.1. Occupancy exemptions. Storage, use and handling of hazardous materials in accordance with Table 307.1.1 of the Cali- fornia Building Code shall not be counted as contributing to maximum allowable quantities and shall not cause classification of an occupancy to be Group H. Such storage, use and handling shall comply with applicable provisions of this code.

203.6.2 Hazardous materials. Hazardous materials in any quantity shall conform to the requirements of this code and Section 414 of the California Building Code .

203.6.3 High-hazard Group H-1. Buildings and structures containing materials that pose a detonation hazard shall be classified as Group H-1. Such materials shall include, but not be limited to, the following:

Detonable pyrophoric materials

Explosives:

Division 1.1

Division 1.2

Division 1.3

Division 1.4

Division 1.5

Division 1.6

Organic peroxides, unclassified detonable

Oxidizers, Class 4

Unstable (reactive) materials, Class 3 detonable and Class 4

203.6.3.1 Occupancies containing explosives not classified as H-1. The following occupancies containing explosive materials shall be classified as follows:
1. Division 1.3 explosive materials that are used and maintained in a form where either confinement or configuration will not elevate the hazard from a mass fire to mass explosion hazard shall be allowed in Group H-2 occupancies.
2. Division 1.4 explosive materials shall be allowed in Group H-3 occupancies.
3. Articles, including articles packaged for shipment, that are not regulated as a Division 1.4 explosive under Bureau of Alcohol, Tobacco, Firearms and Explosives regulations, or unpackaged articles used in process operations that do not propagate a detonation or deflagration between articles shall be allowed in Group H-3 occupancies.
203.6.4 High-hazard Group H-2. Buildings and structures containing materials that pose a deflagration hazard or a hazard from accelerated burning shall be classified as Group H-2. Such materials shall include, but not be limited to, the following:

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DEFINITIONS

Class I, II or IIIA flammable or combustible liquids that are used or stored in normally open containers or systems, or in closed containers or systems pressurized at more than 15 pounds per square inch gauge (103.4 kPa)

Combustible dusts where manufactured, generated or used in such a manner that the concentration and conditions create a fire or explosion hazard based on information prepared in accordance with Section 414.1.3 of the California Building Code.

Cryogenic fluids, flammable

Category 1A flammable gases

Category 1B flammable gases having a burning velocity greater than 3.9 inches per second (99 mm/s)

Organic peroxides, Class I
CBC § 3-5 High relevance — show source text
304 Business Group B. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-5

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

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

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

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

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

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

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

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

313 Laboratories Group L [SFM]. . . . . . . . . . . . . . . . . . . . . . .3-19

314 Organized Camps Group C [SFM]. . . . . . . . . . . . . . . . . .3-19

CHAPTER 4 SPECIAL DETAILED REQUIREMENTS

BASED ON OCCUPANCY AND USE . . . . . . . . . . . . . . . . . . . .4-1

401 Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-5

402 Covered Mall and Open Mall Buildings . . . . . . . . . . . . 4-5

403 High-Rise Buildings and Group I-2 Occupancies Having Occupied Floors Located More Than 75 Feet above the Lowest Level of

Fire Department Vehicle Access . . . . . . . . . . . . . . . 4-9

404 Atriums. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-12

405 Underground Buildings . . . . . . . . . . . . . . . . . . . . . . . . 4-13

406 Motor-Vehicle-Related Occupancies. . . . . . . . . . . . . 4-15

407 Group I-2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-19

408 Group I-3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-24
CBC § 307.3 High relevance — show source text
[F] 307.3 High-hazard Group H-1. Buildings and structures containing materials that pose a detonation hazard shall be classified as Group H-1. Such materials shall include, but not be limited to, the following:

Detonable pyrophoric materials

Explosives:

Division 1.1

Division 1.2

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Division 1.3

Division 1.4

Division 1.5

Division 1.6

Organic peroxides, unclassified detonable

Oxidizers, Class 4

Unstable (reactive) materials, Class 3 detonable and Class 4

[F] 307.3.1 Occupancies containing explosives not classified as H-1. The following occupancies containing explosive materials shall be classified as follows:
1. Division 1.3 explosive materials that are used and maintained in a form where either confinement or configuration will not elevate the hazard from a mass fire to mass explosion hazard shall be allowed in Group H-2 occupancies.
2. Division 1.4 explosive materials shall be allowed in Group H-3 occupancies.
3. Articles, including articles packaged for shipment, that are not regulated as a Division 1.4 explosive under Bureau of Alcohol, Tobacco, Firearms and Explosives regulations, or unpackaged articles used in process operations that do not propagate a detonation or deflagration between articles shall be allowed in Group H-3 occupancies.
[F] 307.4 High-hazard Group H-2. Buildings and structures containing materials that pose a deflagration hazard or a hazard from accelerated burning shall be classified as Group H-2. Such materials shall include, but not be limited to, the following:

Class I, II or IIIA flammable or combustible liquids that are used or stored in normally open containers or systems, or in closed containers or systems pressurized at more than 15 pounds per square inch gauge (103.4 kPa).

Combustible dusts where manufactured, generated or used in such a manner that the concentration and conditions create a fire or explosion hazard based on information prepared in accordance with Section 414.1.3.

Cryogenic fluids, flammable.

Category 1A flammable gases.

Category 1B flammable gases having a burning velocity greater than 3.9 inches per second (10 cm/s).

Organic peroxides, Class I.

Oxidizers, Class 3, that are used or stored in normally open containers or systems, or in closed containers or systems pressurized at more than 15 pounds per square inch gauge (103 kPa).

Pyrophoric liquids, solids and gases, nondetonable.

Unstable (reactive) materials, Class 3, nondetonable.

Water-reactive materials, Class 3.

[F] 307.5 High-hazard Group H-3. Buildings and structures containing materials that readily support combustion or that pose a physical hazard shall be classified as Group H-3. Such materials shall include, but not be limited to, the following:

Class I, II or IIIA flammable or combustible liquids that are used or stored in normally closed containers or systems pressurized at 15 pounds per square inch gauge (103.4 kPa) or less
CBC § 1-33 High relevance — show source text
112 Service Utilities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-33

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

313 Laboratories Group L [SFM]. . . . . . . . . . . . . . . . . . . . . . .3-19
CBC § 2.3. High relevance — show source text
1 to 2.3._ Exception: The gap-to-side plate thickness ratio shall be permitted to be modified for moment connections with unequal beam sizes on opposite sides of the column or when orthogonal beams acting as drag connections frame into the side plate. 8. Demand critical fillet welds {2}, {5}, {5a} and {7} shall have Magnetic Particle Testing (MT) in accordance with AWS D1.1 for procedure, technique and acceptance. Inspect the beginning and end of these welds for a 6-inch length, plus any location along the length of the weld where a start and restart is visually noted for a distance of 6 inches on either side of the start/stop location.

2202.4.3 Modifications to AISC 358 Chapter 11 Bolted Moment Connection The bolted sideplate steel moment connection shall be permitted, provided: 1. The beams shall consist of either rolled or built-up wide flange sections. Columns shall consist of rolled or built-up wide flange sections or noncomposite built-up box or HSS with a minimum wall thickness of [3] / 4 inch (19 mm), or satisfy the requirements of width-to-thickness ratios of highly ductile members in AISC 341-16. 2. The biaxial dual-strong axis and column minor axis configurations of the moment connection shall be considered as an alternative system. 3. For SMF and IMF systems, on the sideplate standard or configuration A the U-shaped cover plates shall be used with the k dimension extension. The k dimension extension length is defined as beam depth d b /6, rounded to the nearest [1] / 2 inch (12.7 mm).

4. The hinge-to-hinge span to beam depth, L h /d, shall be greater than or equal to 4.5. 5. The width-to-thickness ratios for beam flanges shall not be less than 3.5. Exception: For width-to-thickness ratios less than 3.5 the C pr shall be calculated in accordance with that for welded side- plate connections but in no case shall the width-to-thickness ratio be less than 3.0. 6. The minimum bolt-to-bolt spacing shall not be less than 3 bolt diameters. 7. The extension of the side plates beyond the face of the column shall be within the range of 0.65d to 1.5d. 8. The gap-to-side plate thickness ratio shall range from 2.1 to 2.3.

Exception: The gap-to-side plate thickness ratio shall be permitted to be modified for moment connections with unequal beam sizes on opposite sides of the column or when orthogonal beams acting as drag connections frame into the side plate. 9. Demand Critical fillet welds {2}, {5}, {5a} and {8} shall have Magnetic Particle Testing (MT) in accordance with AWS D1.1 for procedure, technique and acceptance. Inspect the beginning and end of these welds for a 6-inch (152 mm) length, plus any location along the length of the weld where a start and restart is visually noted for a distance of 6 inches (152 mm) on either side of the start/stop location. 10. The connection specific factor to account for peak connection strength, C pr _, shall be between 1.15 and 1.35.
CBC § 317.3.2 High relevance — show source text
2. There are changes in risk category. 3. The modification to the structural components increases the seismic forces in or strength requirements of any structural component of the existing structure by more than 10 percent cumulative since the original construction, unless the component has the capacity to resist the increased forces determined in accordance with Section 319. If the building’s seismic base shear capacity has been increased since the original construction, the percent change in base shear may be calculated relative to the increased value.

4. Structural elements need repair where the damage has reduced the lateral-load-resisting capacity of the structural system by more than 10 percent. 5. Changes in live or dead load increase story shear by more than 10 percent.

317.3.2 Public school buildings. [DSA-SS] For public schools, the provisions of Section 317 apply when required in accordance with Sections 4-307 and 4-309(c) of the California Administrative Code.

317.3.3 Community college buildings. [DSA-SS/CC] For community colleges, the provisions of Section 317 apply when required in accordance with Sections 4-307 and 4-309(c) of the California Administrative Code.

317.4 Evaluation required. If the criteria in Section 317.3 apply to the project under consideration, the design professional of record shall provide an evaluation in accordance with Section 317 to determine the seismic performance of the building in its current configuration and condition. If the structure's seismic performance as required by Section 317.5 is evaluated as satisfactory and the peer reviewer(s), when Method B of Section 321 is used, concur, then no structural retrofit is required.

317.5 Minimum seismic design performance levels for structural and nonstructural components. Following the notations of ASCE 41, the seismic requirements for design and assessment are based upon a prescribed Seismic Hazard Level (BSE-1N, BSE-2N, BSE-1E, BSE-R or BSE-C), a specified structural performance level (S-1 through S-5) and a nonstructural performance level (N-A through N-E). The minimum seismic performance criteria are given in Table 317.5 according to the Building Regulatory Authority and the Risk Category as determined in Chapter 16 of the California Building Code or by the regulatory authority. The building shall be evaluated in accordance with a Tier 3 Systematic Evaluation and Retrofit per ASCE 41 Chapter 6 for both the Level 1 and Level 2 performance levels, and the more restrictive requirements shall apply.

Exception: If the floor area of an addition is greater than the larger of 50 percent of the floor area of the original building or 1,000 square feet (93 m [2] ), then the Table 317.5 entries for BSE-R (or BSE-1E) and BSE-C are replaced by BSE-1N and BSE-2N, respectively.

|TABLE 317.5—SEISMIC PERFORMANCE REQUIREMENTS2,
CBC § 0.63 Medium relevance — show source text
For shear loads of normal or permanent load duration as defined by the ANSI/AWC NDS, the values in the table shall be multiplied by 0.63 or 0.56, respectively.
g. For Case 1 through 6 descriptions see Figure 2306.2(1).|For SI: 1 inch = 25.4 mm, 1 pound per foot = 14.5939 N/m.
a. For framing of other species: (1) Find specific gravity for species of lumber in ANSI/AWC NDS. (2) For staples find shear value from table for Structural I panels (regardless of
actual grade) and multiply value by 0.82 for species with specific gravity of 0.42 or greater, or 0.65 for all other species.
b. Space fasteners maximum 12 inches on center along intermediate framing members (6 inches on center where supports are spaced 48 inches on center).
c. Framing at adjoining panel edges shall be 3 inches nominal or wider.
d. Staples shall have a minimum crown width of7/16 inch and shall be installed with their crowns parallel to the long dimension of the framing members.
e. The minimum nominal width of framing members not located at boundaries or adjoining panel edges shall be 2 inches.
f. For shear loads of normal or permanent load duration as defined by the ANSI/AWC NDS, the values in the table shall be multiplied by 0.63 or 0.56, respectively.
g. For Case 1 through 6 descriptions see Figure 2306.2(1).|For SI: 1 inch = 25.4 mm, 1 pound per foot = 14.5939 N/m.
a. For framing of other species: (1) Find specific gravity for species of lumber in ANSI/AWC NDS. (2) For staples find shear value from table for Structural I panels (regardless of
actual grade) and multiply value by 0.82 for species with specific gravity of 0.42 or greater, or 0.65 for all other species.
b. Space fasteners maximum 12 inches on center along intermediate framing members (6 inches on center where supports are spaced 48 inches on center).
c. Framing at adjoining panel edges shall be 3 inches nominal or wider.
d. Staples shall have a minimum crown width of7/16 inch and shall be installed with their crowns parallel to the long dimension of the framing members.
e. The minimum nominal width of framing members not located at boundaries or adjoining panel edges shall be 2 inches.
f. For shear loads of normal or permanent load duration as defined by the ANSI/AWC NDS, the values in the table shall be multiplied by 0.63 or 0.56, respectively.
g. For Case 1 through 6 descriptions see Figure 2306.2(1).|For SI: 1 inch = 25.4 mm, 1 pound per foot = 14.5939 N/m.
a. For framing of other species: (1) Find specific gravity for species of lumber in ANSI/AWC NDS. (2) For staples find shear value from table for Structural I panels (regardless of
actual grade) and multiply value by 0.82 for species with specific gravity of 0.42 or greater, or 0.65 for all other species.
b. Space fasteners maximum 12 inches on center along intermediate framing members (6 inches on center where supports are spaced 48 inches on center).
c.
CBC § 301.1 Medium relevance — show source text
ICC code development note: Code change proposals to sections preceded by the designation [F] will be considered by the IFC code development committee meeting during the 2024 (Group A) Code Development Cycle. All other code change proposals will be considered by a code development committee meeting during the 2025 (Group B) Code Development Cycle.

SECTION 301—SCOPE

301.1 General. The provisions of this chapter shall control the classification of all buildings and structures as to occupancy and use. Different classifications of occupancy and use represent varying levels of hazard and risk to building occupants and adjacent properties.

SECTION 302—OCCUPANCY CLASSIFICATION AND USE DESIGNATION

302.1 Occupancy classification. Occupancy classification is the formal designation of the primary purpose of the building, structure or portion thereof. Structures shall be classified into one or more of the occupancy groups specified in this section based on the nature of the hazards and risks to building occupants generally associated with the intended purpose of the building or structure. An area, room or space that is intended to be occupied at different times for different purposes shall comply with all applicable requirements associated with such potential multipurpose. Structures containing multiple occupancy groups shall comply with Section 508. Where a structure is proposed for a purpose that is not specified in this section, such structure shall be classified in the occupancy it most nearly resembles based on the fire safety and relative hazard. Occupiable roofs shall be classified in the group that the occupancy most nearly resembles, according to the fire safety and relative hazard, and shall comply with Section 503.1.4.
1. Assembly (see Section 303): Groups A-1, A-2, A-3, A-4 and A-5.
2. Business (see Section 304): Group B. 3. [SFM] Organized Camps (see Section 450): Group C. 4. Educational (see Section 305): Group E. 5. Factory and Industrial (see Section 306): Groups F-1 and F-2. 6. High Hazard (see Section 307): Groups H-1, H-2, H-3, H-4 and H-5. 7. Institutional (see Section 308): Groups I-2, I-3 and I-4. 8. [SFM] Laboratory (see Section 202): Group B, unless classified as Group L (see Section 453) or Group H (see Section 307). 9. [SFM] Laboratory Suites (see Section 453): Group L. 10. Mercantile (see Section 309): Group M. 11 . Residential (see Section 310): Groups R-1, R-2, R-2.1, R-3, R-3.1 and R-4. 12 . Storage (see Section 311): Groups S-1 and S-2. 13 . Utility and Miscellaneous (see Section 312): Group U. 14. [SFM] Existing buildings housing existing protective social care homes or facilities established prior to 1972 (see California Fire Code Chapter 11 and California Existing Building Code).
302.1.1 Reserved

302.1.2 Reserved

302.1.3 Pharmacies; veterinary facilities; barbering, cosmetology or electrolysis establishments; and acupuncture offices. See Chapter 12.

CBC § 2.1 Medium relevance — show source text

The IBC requirements for hazardous materials, fire-resistance-rated construction, interior finish, fire protection systems, means of egress, emergency and standby power, and temporary structures are directly correlated with the requirements of the International Fire Code ® (IFC®). The following table shows chapters/sections of the IBC that are correlated with the IFC:

IBC/IFC CORRELATED TOPICS	Col2	Col3
IBC CHAPTER/SECTION	IFC CHAPTER/SECTION	SUBJECT
Sections 307, 414, 415	Chapters 50–67	Hazardous materials and Group H requirements
Chapter 7	Chapter 7	Fire-resistance-rated construction (fire and smoke protection features in the IFC)
Chapter 8	Chapter 8	Interior finish, decorative materials and furnishings
Chapter 9	Chapter 9	Fire protection systems
Chapter 10	Chapter 10	Means of egress
Chapter 27	Section 604	Standby and emergency power
Section 3103	Chapter 31	Temporary structures

Chapter 1 Scope and Administration.

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

Chapter 2 Definitions.

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

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Chapter 3 Occupancy Classification and Use.

Chapter 3 provides for the classification of buildings, structures and parts thereof based on the purpose for which they are used. Section 302 identifies the groups into which all buildings, structures and parts thereof must be classified. Sections 303 through 312 identify the occupancy characteristics of each group classification. In some sections, specific group classifications having requirements in common are collectively organized such that one term applies to all. For example, Groups A-1, A-2, A-3, A-4 and A-5 are individual groups for assembly-type buildings. The general term “Group A,” however, includes each of these individual groups. Other groups include Business (B), Organized Camps (C), Educational (E), Factory (F-1, F-2), High Hazard (H-1, H-2, H-3, H-4, H-5), Institutional (I-2, I-3, I-4), Laboratories (L), Mercantile (M), Residential (R-1, R-2, R-2.1, R-2.2, R-3, R-3.1, R-4), Storage (S-1, S-2) and Utility (U). In some occupancies, the smaller number means a higher hazard, but that is not always the case.

CBC § 903.2.5 Medium relevance — show source text
903.2.5

Ventilation 414.3, 415.9.1.7, 415.11.1.6, 415.11.1.8.1, 415.11.3.2, 415.11.6.8, 415.11.7.4, 415.11.8, 415.11.11, 1202.6 Weather protection 414.6.1 Hazardous Occupancy (Group H), (see Hazardous Materials) 307, 414, 415 Alarms and detection 415.11.2, 415.11.4, 415.11.6.9, 415.11.8, 415.3, 415.5, 907.2.5, 908.1, 908.2 Area 503, 505, 506, 507, 508 Dispersing 414.5, 414.6, 415.6 Gas detection systems 415.11.7 Group provisions H-1 (detonation) 307.3, 415.6.2, 415.7, 415.6.4.1, 415.7.1 H-2 (deflagration) 307.4, 415.8, 415.9 H-3 (physical hazard) 415.10, 307.5, 415.8 H-4 (health hazard) 307.6, 415.10 H-5 (semiconductor) 307.7, 415.11 Height 415.7, 415.8.1, 415.9.1.1, 426.1.1, 503, 504, 505, 506 Incidental uses 509

Interior finishes 416.2.1, 416.3.1, Table 803.13, 804 Live load Table 1607.1

Location on property 414.6.1.2, 415.6 Low hazard 306.3, 311.3 Means of egress Corridors 415.11.2 One means of egress Table 1006.3.4(1), Table 1006.3.4(2) Panic hardware 1006.2.2.2, 1006.2.2.3, 1006.2.2.4, 1010.2.8 Stairway, exit access 1019 Travel distance 1006.3, 1006.2.1, Table 1017.2

Mixed occupancies 508.3, 508.4 Accessory 508.2 Moderate hazard 306.2, 311.2 Multiple hazards 306.2, 311.2 Occupancy exceptions 307.1 Plumbing fixtures Chapter 29 Risk category Table 1604.5 Separation from other occupancies 415.6.1, 508.1, 508.2.4, 508.3.3, 508.4 Smoke and heat removal 910.2 Special provisions based on materials Combustible liquids Table 307.1(1), 307.4, 307.5, 414.2.5, 414.5.3,

415.9.2

Corrosives 307.6, Table 414.2.5.1, 414.3, 415.10.3, Table 415.11.1.1 Explosives 307.3, 307.3.1, Table 415.6.5
CBC § 2506.2 High relevance — show source text
Vertical and horizontal assemblies

2504

Wallboard Table 2506.2, 2508.2, 2508.2.1, 2508.4, 2510.5.2.1 Water-resistant backing board 2506.2, 2509.2

Habitable Space 1208 Handrails 1014 Alternating tread devices 1011.14 Assembly aisles 1030.16 Construction 1014.5, 1014.6, 1014.7 Extensions 1014.7 Glazing 2407 Graspability 1014.4 Guards 1015.3 Height 1014.2 Loads 1607.9

Location 1014.1, 1014.8, 1014.9,

1014.10

Ramps 1012.8 Stairs 1011.11

Hardboard 1403.3.2, 2303.1.7 Hardware (see Doors and Locks and Latching) Hardwood

Fastening 2304.10 Quality 2303.3 Veneer 1403.3.2 Hazardous Materials 307, 414, 415 Compliance with California Fire Code 307.2

Control areas 414.2

Explosion control 414.5.1, Table 414.5.1, 415.11.6.5, 426.1.4 Mercantile occupancies 309.2 Reporting 414.1.3 Sprinkler protection Table 414.2.5.1, Table 414.2.5.2, 415.4, 415.11.12,

903.2.5

Ventilation 414.3, 415.9.1.7, 415.11.1.6, 415.11.1.8.1, 415.11.3.2, 415.11.6.8, 415.11.7.4, 415.11.8, 415.11.11, 1202.6 Weather protection 414.6.1 Hazardous Occupancy (Group H), (see Hazardous Materials) 307, 414, 415 Alarms and detection 415.11.2, 415.11.4, 415.11.6.9, 415.11.8, 415.3, 415.5, 907.2.5, 908.1, 908.2 Area 503, 505, 506, 507, 508 Dispersing 414.5, 414.6, 415.6 Gas detection systems 415.11.7 Group provisions H-1 (detonation) 307.3, 415.6.2, 415.7, 415.6.4.1, 415.7.1 H-2 (deflagration) 307.4, 415.8, 415.9 H-3 (physical hazard) 415.10, 307.5, 415.8 H-4 (health hazard) 307.6, 415.10 H-5 (semiconductor) 307.7, 415.11 Height 415.7, 415.8.1, 415.9.1.1, 426.1.1, 503, 504, 505, 506 Incidental uses 509
CBC § 414.1 High relevance — show source text
Exception: Neither fire-resistance-rated construction nor opening protectives are required in any of the following locations:
1. Areas protected by approved automatic sprinkler systems.
2. Group R-3 and U occupancies.
SECTION 414—HAZARDOUS MATERIALS

[F] 414.1 General. Buildings and structures occupied for the manufacturing, processing, dispensing, use or storage of hazardous materials shall comply with Sections 414.1 through 414.6.

Exception: Exemptions listed in Table 307.1.1 shall not be required to comply with Section 414.

[F] 414.1.1 Other provisions. Buildings and structures with an occupancy in Group H shall comply with this section and the applicable provisions of Section 415 and the California Fire Code. See Section 453 for Group L occupancies.

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SPECIAL DETAILED REQUIREMENTS BASED ON OCCUPANCY AND USE

[F] 414.1.2 Materials. The safe design of hazardous material occupancies is material dependent. Individual material requirements are found in Sections 307 and 415, the California Mechanical Cod e and the California Fire Code.

[F] 414.1.2.1 Aerosol products, aerosol cooking spray products and plastic aerosol 3 products. Level 2 and 3 aerosol products, aerosol cooking spray products and plastic aerosol 3 products shall be stored and displayed in accordance with the California Fire Code . See Section 311.2 and the California Fire Code for occupancy group requirements.

[F] 414.1.3 Information required. A report shall be submitted to the building official identifying the maximum expected quantities of hazardous materials to be stored, used in a closed system and used in an open system, and subdivided to separately address hazardous material classification categories based on Tables 307.1(1) and 307.1(2). The methods of protection from such hazards, including but not limited to control areas, fire protection systems and Group H occupancies shall be indicated in the report and on the construction documents. The opinion and report shall be prepared by a qualified person, firm or corporation approved by the building official and provided without charge to the enforcing agency.

For buildings and structures with an occupancy in Group H, separate floor plans shall be submitted identifying the locations of anticipated contents and processes so as to reflect the nature of each occupied portion of every building and structure.

[F] 414.2 Control areas. Control areas shall comply with Sections 414.2.1 through 414.2.5 and the California Fire Code .

[F] 414.2.1 Construction requirements. Control areas shall be separated from each other by fire barriers constructed in accordance with Section 707 or horizontal assemblies constructed in accordance with Section 711, or both.

[F] 414.2.2 Percentage of maximum allowable quantities. The percentage of maximum allowable quantities of hazardous materials per control area permitted at each floor level within a building shall be in accordance with Table 414.2.2.
CBC § 903.3.1.1. High relevance — show source text
Hazard categories are as specified in the_California Fire Code_.
b. Maximum allowable quantities shall be increased 100 percent in buildings that are sprinklered in accordance with Section 903.3.1.1. Where Note c also applies, the increase
for both notes shall be applied accumulatively.
c. Maximum allowable quantities shall be increased 100 percent where stored in approved storage cabinets, in accordance with the_California Fire Code_. Where Note b also
applies, the increase for both notes shall be applied accumulatively.
d. See Table 414.2.2 for design and number of control areas.
e. Allowable quantities for other hazardous material categories shall be in accordance with Section 307.
f. Maximum quantities shall be increased 100 percent in outdoor control areas.
g. Maximum amounts shall be increased to 2,250 pounds where individual packages are in the original sealed containers from the manufacturer or packager and do not exceed
10 pounds each.
h. Maximum amounts shall be increased to 4,500 pounds where individual packages are in the original sealed containers from the manufacturer or packager and do not exceed
10 pounds each.
i. The permitted quantities shall not be limited in a building equipped throughout with an automatic sprinkler system in accordance with Section 903.3.1.1.
j. Quantities are unlimited in an outdoor control area.
k. Maximum allowable quantities of consumer products shall be increased to 10,000 pounds where individual packages are in the original, sealed containers from the manufac-
turer and the toxic classification is exclusively based on the LC threshold and no other hazardous materials classifications apply.|For SI: 1 pound = 0.454 kg, 1 gallon = 3.785 L.
a. Hazard categories are as specified in the_California Fire Code_.
b. Maximum allowable quantities shall be increased 100 percent in buildings that are sprinklered in accordance with Section 903.3.1.1. Where Note c also applies, the increase
for both notes shall be applied accumulatively.
c. Maximum allowable quantities shall be increased 100 percent where stored in approved storage cabinets, in accordance with the_California Fire Code_. Where Note b also
applies, the increase for both notes shall be applied accumulatively.
d. See Table 414.2.2 for design and number of control areas.
e. Allowable quantities for other hazardous material categories shall be in accordance with Section 307.
f. Maximum quantities shall be increased 100 percent in outdoor control areas.
g. Maximum amounts shall be increased to 2,250 pounds where individual packages are in the original sealed containers from the manufacturer or packager and do not exceed
10 pounds each.
h. Maximum amounts shall be increased to 4,500 pounds where individual packages are in the original sealed containers from the manufacturer or packager and do not exceed
10 pounds each.
i. The permitted quantities shall not be limited in a building equipped throughout with an automatic sprinkler system in accordance with Section 903.3.1.1.
j. Quantities are unlimited in an outdoor control area.
k. Maximum allowable quantities of consumer products shall be increased to 10,000 pounds where individual packages are in the original, sealed containers from the manufac-
turer and the toxic classification is exclusively based on the LC threshold and no other hazardous materials classifications apply.|For SI: 1 pound = 0.454 kg, 1 gallon = 3.785 L.
a.

CBC § 3-7 Medium relevance — show source text

Hazardous occupancies are classified in Groups H-1, H-2, H-3, H-4 and H-5 and shall be in accordance with this section, the requirements of Section 415 and the California Fire Code . Hazardous materials stored or used on top of roofs or canopies shall be classified as rooftop storage or use and shall comply with the California Fire Code .

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OCCUPANCY CLASSIFICATION AND USE

[F] TABLE 307.1(1)—MAXIMUM ALLOWABLE QUANTITY PER CONTROL AREA OF HAZARDOUS MATERIALS POSING A PHYSICAL HAZARDa, i, l, m	Col2	Col3	Col4	Col5	Col6	Col7	Col8	Col9	Col10	Col11
MATERIAL	CLASS	GROUP WHEN THE MAXIMUM ALLOWABLE QUANTITY IS EXCEEDED	STORAGEb	STORAGEb	STORAGEb	USE-CLOSED SYSTEMSb	USE-CLOSED SYSTEMSb	USE-CLOSED SYSTEMSb	USE-OPEN SYSTEMSb	USE-OPEN SYSTEMSb
MATERIAL	CLASS	GROUP WHEN THE MAXIMUM ALLOWABLE QUANTITY IS EXCEEDED	Solid pounds (cubic feet)	Liquid gallons (pounds)	Gas (cubic feet at NTP)	Solid pounds (cubic feet)	Liquid gallons (pounds)	Gas (cubic feet at NTP)	Solid pounds (cubic feet)	Liquid gallons (pounds)
Combustible dust	NA	H-2	See Note o	NA	NA	See Note o	NA	NA	See Note o	NA
Combustible fibero	Loose	H-3	(100)	NA	NA	(100)	NA	NA	(20)	NA
Combustible fibero	Baled	Baled	(1,000)	(1,000)	(1,000)	(1,000)	(1,000)	(1,000)	(200)	(200)
Combustible liquidn	II	H-2 or H-3	NA	120d, e	NA	NA	120d	NA	NA	30d
Combustible liquidn	IIIA	H-2 or H-3	H-2 or H-3	330d, e	330d, e	330d,

Frequently asked questions

How do I know whether to use the “storage” or “use” columns in Table 307.1(1)?

Use the column that matches how the material is being kept or handled in the control area: storage (on racks, in cabinets, tanks) vs. use in a closed‑system vs. open‑system use. Table 307.1(1) has separate columns for these conditions — pick the column reflecting your actual operation.

If my building is sprinklered, can I store twice the table amount?

Some table notes allow a 100% increase where the building is sprinklered in accordance with the referenced sprinkler section; these increases are conditional and cumulative with other applicable notes (e.g., approved cabinets). Apply the notes exactly as written in Table 307.1(1).

Does exceeding a table quantity automatically change the entire building to Group H?

Exceeding a table quantity in a control area causes that area (or fire area as defined by the code) to be treated as Group H for the purposes of the code. Mixed‑occupancy separation rules, control‑area boundaries and Section 508 accessory/mixed‑occupancy rules also affect how the remainder of the building is classified — consult those sections and § 414/§ 415 for implementation.

Where do I get the formal report required by § 414.1.3?

The code requires a report prepared by a qualified person acceptable to the building official that lists the maximum expected quantities by material and by storage/use condition and describes proposed protections (control areas, sprinklers, Group H designation). Provide that report to the enforcing agency per § 414.1.3.

My material isn't listed in the excerpted table — what do I do?

Consult the full Table 307.1(1) in the published CBC and the California Fire Code (for hazard classifications and cross‑references). If uncertainty remains, submit the § 414.1.3 report and obtain a determination from the building official; don’t invent a numeric limit.

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Educational Group E — schools and child‑care classification rules

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High‑hazard Group H — classification criteria and tables

What the code requires — 2-4 sentences

Requirements in detail

Basic rule and how to use the table

Key numeric thresholds (decision‑relevant excerpts from Table 307.1(1))

Group definitions that control classification

Reporting and documentation

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