CBC · California Building Code

Control-area separation, construction & sprinkler adjustments

The CBC requires hazardous‑material control areas to be separated by fire barriers/horizontal assemblies, limits quantities by story using Table 414.2.2, sets fire‑resistance requirements for barriers and floors, and provides higher allowances where the building is sprinklered — with specific product allowances (for example Category 1B flammable gas) in § 414.2.5 and its tables; detailed sprinkler design and storage arrangement rules are in the California Fire Code.

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Last reviewed: July 5, 2026

What the code requires — 2-4 sentences

Control areas (subdivisions used to limit quantities of hazardous materials) must be separated from one another by fire barriers or horizontal assemblies and must comply with the quantity limits and construction, fire‑resistance and sprinkler rules laid out in Section 414. The CBC prescribes the allowed percentage of the maximum allowable quantity per control area by story (Table 414.2.2), requires specified fire‑resistance for barriers and floors (§ 414.2.4), and contains special provisions for hazardous materials in Group M and S display/storage areas (§ 414.2.5). See § 414.2 and its subsections for the controlling requirements.

Requirements in detail

1) Separation and basic construction

  • Control areas must be separated from each other by fire barriers constructed per Section 707 or by horizontal assemblies constructed per Section 711 (or both). This is the construction requirement for control‑area separation. See § 414.2.1.

  • The required fire‑resistance rating for fire barriers and for the floor assembly supporting a control area is specified by Table 414.2.2 and § 414.2.4; the floor assembly is generally required to be 2 hours. An exception allows the floor assembly to be 1 hour in certain construction types when the building is sprinklered and is three stories or fewer above grade plane. See § 414.2.4.

2) How much hazardous material is allowed — by story and number of control areas

The CBC limits the percentage of the "maximum allowable quantity per control area" (from Tables 307.1(1) and 307.1(2)) that may be placed in each control area based on story level, and limits the number of control areas per story. The key dimension values you’ll use when deciding compliance are in Table 414.2.2 (excerpt shown below). See § 414.2 and Table 414.2.2.

Decision dimension Typical value (percent or count) Code Reference
Percent of maximum allowable quantity per control area — 1st story (above grade plane) 100% § 414.2 / Table 414.2.2
Percent per control area — 2nd story 75% § 414.2 / Table 414.2.2
Percent per control area — 3rd story 50% § 414.2 / Table 414.2.2
Percent per control area — 4th–6th stories 12.5% (4–6 vary in table) § 414.2 / Table 414.2.2
Percent per control area — stories 7 and higher 5% § 414.2 / Table 414.2.2
Fire‑resistance rating for fire barriers (typical) 1–2 hours as required by Table 414.2.2; floor assembly 2 hours (exception allows 1 hour) § 414.2.4
Separation method Fire barrier (Sec. 707) or horizontal assembly (Sec. 711) § 414.2.1
Number of control areas per story See Table 414.2.2 (varies by story) § 414.2.3 and Table 414.2.2

Notes:

  • Percentages in Table 414.2.2 are percentages of the maximum allowable quantity per control area in Tables 307.1(1) and 307.1(2) (including any increases allowed in the notes to those tables). See § 414.2 and the table notes.

3) Sprinkler adjustments and special allowances for Group M / S display & storage areas

  • Section 414.2.5 contains special rules for hazardous materials located in Group M (mercantile) display and storage areas and Group S storage areas. It delegates material‑specific allowances to the following subsections (§ 414.2.5.1–.4). See § 414.2.5.

  • For low‑burning‑velocity Category 1B flammable gas in Group M or Group S control areas, CBC Table 414.2.5.4 gives explicit maximum allowable quantities per control area for sprinklered and nonsprinklered conditions. For example (Table 414.2.5.4):

    • Sprinklered: Gaseous Category 1B — 390,000 cu ft per control area; Liquefied — 40,000 lb per control area.
    • Nonsprinklered: Gaseous Category 1B — 195,000 cu ft per control area; Liquefied — 20,000 lb per control area. See Table 414.2.5.4 and § 414.2.5.4.

  • The CBC requires that, to be considered sprinklered for these allowances, “the building shall be equipped throughout with an approved automatic sprinkler system with a minimum sprinkler design density of Ordinary Hazard Group 2 in the area where flammable gases are stored or displayed.” That sprinkler density detail is provided in the Fire Code and referenced by § 414.2.5.4; consult the California Fire Code for design densities and arrangement. See § 414.2.5.4 and the referenced California Fire Code.

  • For very large wholesale/retail storage areas (>50,000 sq ft) the code allows increases to the maximum allowable quantities by a 2% increment for each additional 1,000 sq ft (up to certain limits) and in some cases eliminates the need for control‑area separation; special aggregate caps and conditions apply — see Table 414.2.5.4 notes and the California Fire Code references. See § 414.2.5.4 notes.

Exceptions & special cases

  • Floor assembly fire‑resistance can be reduced from 2 hours to 1 hour in Types IIA, IIIA, IV and VA construction only if both of the following are met: (1) the building is equipped throughout with an automatic sprinkler system per § 903.3.1.1, and (2) the building is three stories or fewer above grade plane. See the exception in § 414.2.4.

  • The CBC defers many detailed storage, shelving, and sprinkler design requirements to the California Fire Code; where § 414.2.5 refers to maximum quantities for specific products (aerosols, flammable gases, etc.), the Fire Code contains the design and storage arrangement details you must meet. See § 414.2.5 and the cross references to the CFC.

  • Certain nonflammable solids and noncombustible liquids may be allowed to exceed the Table 307.1 control‑area limits when displayed/stored in Group M or S, provided they meet the California Fire Code storage/display rules and do not exceed the specific amounts in Table 414.2.5.1. See § 414.2.5.1.

Common mistakes

  • Relying only on a “sprinklered building” statement without confirming the sprinkler design density and arrangement required for the allowance (the CBC requires a minimum Ordinary Hazard Group 2 density for many allowances; the Fire Code has the design rules). Always confirm the design density and area of design.

  • Applying the percent allowances from Table 414.2.2 without using the correct base quantities (the percentages are of the maximum allowable quantity per control area in Tables 307.1(1) and 307.1(2), including any increases in those tables’ notes).

  • Forgetting to provide the required report to the building official that identifies maximum expected quantities, control‑area methods, and protection methods as required by § 414.1.3. That report must be prepared by a qualified person and submitted with construction documents.

  • Confusing units in tables (e.g., cubic feet vs pounds for flammable gases, gallons for liquids). Make sure you use the correct units from the table (Table 414.2.5.4 and other tables).

Worked example — concrete scenario

Scenario: A sprinklered Group M retail store occupies a two‑story building. You plan to store low burning‑velocity Category 1B flammable gas (gaseous form) in a control area on the first floor.

Step 1 — Confirm table base allowance:

  • Table 414.2.5.4 lists the maximum allowable quantity of Category 1B (Low BV) gaseous flammable gas per control area as 390,000 cubic feet when sprinklered. See Table 414.2.5.4 and § 414.2.5.4.

Step 2 — Confirm percent by story from Table 414.2.2:

  • For the first (ground) story above grade plane, Table 414.2.2 allows 100% of the maximum allowable quantity per control area. See Table 414.2.2 and § 414.2.

Step 3 — Apply result:

  • Because the building is sprinklered (and the sprinklers must meet the Ordinary Hazard Group 2 minimum design per the related note), the allowed amount in that control area on the first story is 100% × 390,000 cu ft = 390,000 cu ft. Verify sprinkler design density and whole‑building sprinkler condition per the Fire Code before assuming the allowance. See § 414.2.5.4 and the Fire Code references.

If the building were not sprinklered, the table limit for gaseous Category 1B would be 195,000 cu ft per control area (and the same percent by story would apply). See § 414.2.5.4.

Related provisions

  • § 414.1.3 — Information required (report to building official on expected quantities and protection methods).
  • § 414.2.1 — Construction requirements for control‑area separation (fire barriers/horizontal assemblies).
  • § 414.2.3 — Maximum number of control areas; relationship to Table 414.2.2.
  • § 414.2.4 — Fire‑resistance rating requirements and the 1‑hour/2‑hour floor assembly rule and exception.
  • § 414.2.5 (and §§ 414.2.5.1–.4) — Hazardous materials allowances and special rules for Group M and Group S display and storage areas (including Table 414.2.5.4).
  • Section 307 and Tables 307.1(1)/307.1(2) — base maximum allowable quantities that Table 414.2.2 percentages modify.

Code references

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

  • CBC § 3.9 High relevance — show source text

    Control areas shall be separated from each other by not less than a 1-hour fire barrier.
    b. The building shall be equipped throughout with an approved automatic sprinkler system with a minimum sprinkler design density of Ordinary Hazard Group 2 in the area
    where flammable gases are stored or displayed.
    c. Where storage areas exceed 50,000 square feet in area, the maximum allowable quantities area is allowed to be increased by 2 percent for each 1,000 square feet of area in excess
    of 50,000 square feet, up to not more than 100 percent of the table amounts. Separation of control areas is not required. The aggregate amount shall not exceed 80,000 pounds.
    d._ Low Burning Velocity_(Low BV) Category 1B flammable gas has a burning velocity of 3.9 in/s or less.|For SI: 1 pound = 0.454 kg, 1 square foot = 0.0929 m2, 1 cubic foot = 0.028 m3, 1 inch per second = 2.54 cm/s.
    a. Control areas shall be separated from each other by not less than a 1-hour fire barrier.
    b. The building shall be equipped throughout with an approved automatic sprinkler system with a minimum sprinkler design density of Ordinary Hazard Group 2 in the area
    where flammable gases are stored or displayed.
    c. Where storage areas exceed 50,000 square feet in area, the maximum allowable quantities area is allowed to be increased by 2 percent for each 1,000 square feet of area in excess
    of 50,000 square feet, up to not more than 100 percent of the table amounts. Separation of control areas is not required. The aggregate amount shall not exceed 80,000 pounds.
    d._ Low Burning Velocity_(Low BV) Category 1B flammable gas has a burning velocity of 3.9 in/s or less.|For SI: 1 pound = 0.454 kg, 1 square foot = 0.0929 m2, 1 cubic foot = 0.028 m3, 1 inch per second = 2.54 cm/s.
    a. Control areas shall be separated from each other by not less than a 1-hour fire barrier.
    b. The building shall be equipped throughout with an approved automatic sprinkler system with a minimum sprinkler design density of Ordinary Hazard Group 2 in the area
    where flammable gases are stored or displayed.
    c. Where storage areas exceed 50,000 square feet in area, the maximum allowable quantities area is allowed to be increased by 2 percent for each 1,000 square feet of area in excess
    of 50,000 square feet, up to not more than 100 percent of the table amounts. Separation of control areas is not required. The aggregate amount shall not exceed 80,000 pounds.
    d._ Low Burning Velocity_(Low BV) Category 1B flammable gas has a burning velocity of 3.9 in/s or less.|

    [F] 414.3 Ventilation. Rooms, areas or spaces in which explosive, corrosive, combustible, flammable or highly toxic dusts, mists, fumes, vapors or gases are or have the potential to be emitted due to the processing, use, handling or storage of materials shall be mechanically ventilated where required by this code, the California Fire Code or the California Mechanical Code .

    Emissions generated at workstations shall be confined to the area in which they are generated as specified in the California Fire Code and the California Mechanical Code .

  • CBC § 0.21 High relevance — show source text

    For uncartoned commodities on shelves 6 feet or less in height where the ceiling height does not exceed 18 feet, quantities are those permitted with a minimum sprin-
    kler design density of Ordinary Hazard Group 2.
    2. For cartoned, palletized or racked commodities where storage is 4 feet 6 inches or less in height and where the ceiling height does not exceed 18 feet, quantities are
    those permitted with a minimum sprinkler design density of 0.21 gallon per minute per square foot over the most remote 1,500-square-foot area.
    c. Where wholesale and retail sales or storage areas exceed 50,000 square feet in area, the maximum allowable quantities are allowed to be increased by 2 percent for each
    1,000 square feet of area in excess of 50,000 square feet, up to not more than 100 percent of the table amounts. A control area separation is not required. The cumulative
    amounts, including amounts attained by having an additional control area, shall not exceed 30,000 gallons.|For SI: 1 foot = 304.8 mm, 1 square foot = 0.0929 m2, 1 gallon = 3.785 L, 1 gallon per minute per square foot = 40.75 L/min/m2.
    a. Control areas shall be separated from each other by not less than a 1-hour fire barrier wall.
    b. To be considered as sprinklered, a building shall be equipped throughout with an approved automatic sprinkler system with a design providing minimum densities as follows:
    1. For uncartoned commodities on shelves 6 feet or less in height where the ceiling height does not exceed 18 feet, quantities are those permitted with a minimum sprin-
    kler design density of Ordinary Hazard Group 2.
    2. For cartoned, palletized or racked commodities where storage is 4 feet 6 inches or less in height and where the ceiling height does not exceed 18 feet, quantities are
    those permitted with a minimum sprinkler design density of 0.21 gallon per minute per square foot over the most remote 1,500-square-foot area.
    c. Where wholesale and retail sales or storage areas exceed 50,000 square feet in area, the maximum allowable quantities are allowed to be increased by 2 percent for each
    1,000 square feet of area in excess of 50,000 square feet, up to not more than 100 percent of the table amounts. A control area separation is not required. The cumulative
    amounts, including amounts attained by having an additional control area, shall not exceed 30,000 gallons.|For SI: 1 foot = 304.8 mm, 1 square foot = 0.0929 m2, 1 gallon = 3.785 L, 1 gallon per minute per square foot = 40.75 L/min/m2.
    a. Control areas shall be separated from each other by not less than a 1-hour fire barrier wall.
    b. To be considered as sprinklered, a building shall be equipped throughout with an approved automatic sprinkler system with a design providing minimum densities as follows:
    1. For uncartoned commodities on shelves 6 feet or less in height where the ceiling height does not exceed 18 feet, quantities are those permitted with a minimum sprin-
    kler design density of Ordinary Hazard Group 2.
    2.

  • CBC § 307.1 High relevance — show source text

    Percentages shall be of the maximum allowable quantity per control area shown in Tables 307.1(1) and 307.1(2), with all increases allowed in the notes to those tables.
    b. Separation shall include fire barriers and horizontal assemblies as necessary to provide separation from other portions of the building.|

    [F] 414.2.3 Number. The maximum number of control areas within a building shall be in accordance with Table 414.2.2. For the purposes of determining the number of control areas within a building, each portion of a building separated by one or more fire walls complying with Section 706 shall be considered a separate building.

    [F] 414.2.4 Fire-resistance rating requirements. The required fire-resistance rating for fire barriers shall be in accordance with Table 414.2.2. The floor assembly of the control area and the construction supporting the floor of the control area shall have a fireresistance rating of not less than 2 hours.

    Exception: The floor assembly of the control area and the construction supporting the floor of the control area are allowed to be 1-hour fire-resistance-rated in buildings of Types IIA, IIIA, IV and VA construction, provided that both of the following conditions exist:

    1. The building is equipped throughout with an automatic sprinkler system in accordance with Section 903.3.1.1.
    2. The building is three or fewer stories above grade plane.

    [F] 414.2.5 Hazardous material in Group M display and storage areas and in Group S storage areas. Hazardous materials located in Group M and Group S occupancies shall be in accordance with Sections 414.2.5.1 through 414.2.5.4.

    [F] 414.2.5.1 Nonflammable solids and nonflammable and noncombustible liquids. The aggregate quantity of nonflammable solid and nonflammable or noncombustible liquid hazardous materials permitted within a single control area of a Group M display and storage area, a Group S storage area or an outdoor control area is permitted to exceed the maximum allowable quantities per control area specified in Tables 307.1(1) and 307.1(2) without classifying the building or use as a Group H occupancy, provided that the materials are displayed and stored in accordance with the California Fire Code and quantities do not exceed the maximum allowable specified in Table 414.2.5.1.

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    SPECIAL DETAILED REQUIREMENTS BASED ON OCCUPANCY AND USE

  • 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 § 414.2.5.4 High relevance — show source text

    [F] 414.2.5.4 Flammable gas. The aggregate quantity of Category 1B flammable gas having a burning velocity of 3.9 inches per second (10 cm/s) or less stored and displayed within a single control area of a Group M occupancy or stored in a single control area of a Group S occupancy is allowed to exceed the maximum allowable quantities per control area specified in Table 307.1(1) without classifying the building or use as a Group H occupancy, provided that the materials are stored and displayed in accordance with the California Fire Code and quantities do not exceed the amounts specified in Table 414.2.5.4.

    [F] TABLE 414.2.5.4—MAXIMUM ALLOWABLE QUANTITY OF LOW BURNING VELOCITY
    CATEGORY 1B FLAMMABLE GAS IN GROUP M AND S OCCUPANCIES PER CONTROL AREAa    		 Col2 Col3
    CATEGORY 1B
    (Low BV)d    		 MAXIMUM ALLOWABLE QUANTITY PER CONTROL AREA MAXIMUM ALLOWABLE QUANTITY PER CONTROL AREA
    CATEGORY 1B
    (Low BV)d    		 Sprinkleredb Nonsprinklered
    Gaseous 390,000 cu ft 195,000 cu ft
    Liquefied 40,000 lbc 20,000 lb
    For SI: 1 pound = 0.454 kg, 1 square foot = 0.0929 m2, 1 cubic foot = 0.028 m3, 1 inch per second = 2.54 cm/s.
    a. Control areas shall be separated from each other by not less than a 1-hour fire barrier.
    b. The building shall be equipped throughout with an approved automatic sprinkler system with a minimum sprinkler design density of Ordinary Hazard Group 2 in the area
    where flammable gases are stored or displayed.
    c. Where storage areas exceed 50,000 square feet in area, the maximum allowable quantities area is allowed to be increased by 2 percent for each 1,000 square feet of area in excess
    of 50,000 square feet, up to not more than 100 percent of the table amounts. Separation of control areas is not required. The aggregate amount shall not exceed 80,000 pounds.
    d._ Low Burning Velocity_(Low BV) Category 1B flammable gas has a burning velocity of 3.9 in/s or less.    		 For SI: 1 pound = 0.454 kg, 1 square foot = 0.0929 m2, 1 cubic foot = 0.028 m3, 1 inch per second = 2.54 cm/s.
    a. Control areas shall be separated from each other by not less than a 1-hour fire barrier.
    b. The building shall be equipped throughout with an approved automatic sprinkler system with a minimum sprinkler design density of Ordinary Hazard Group 2 in the area
    where flammable gases are stored or displayed.
    c. Where storage areas exceed 50,000 square feet in area, the maximum allowable quantities area is allowed to be increased by 2 percent for each 1,000 square feet of area in excess
    of 50,000 square feet, up to not more than 100 percent of the table amounts. Separation of control areas is not required.
  • CBC § 3.9 High relevance — show source text

    Where storage areas exceed 50,000 square feet in area, the maximum allowable quantities area is allowed to be increased by 2 percent for each 1,000 square feet of area in excess
    of 50,000 square feet, up to not more than 100 percent of the table amounts. Separation of control areas is not required. The aggregate amount shall not exceed 80,000 pounds.
    d. “Low BV” Category 1B flammable gas has a burning velocity of 3.9 in/s (10 cm/s) or less.|For SI: 1 pound = 0.454 kg, 1 cubic foot = 0.028 m3.
    a. Control areas shall be separated from each other by not less than a 1-hour fire barrier.
    b. The building shall be equipped throughout with an approved automatic sprinkler system with a minimum sprinkler design density of Ordinary Hazard Group 2 in the area
    where flammable gases are stored or displayed.
    c. Where storage areas exceed 50,000 square feet in area, the maximum allowable quantities area is allowed to be increased by 2 percent for each 1,000 square feet of area in excess
    of 50,000 square feet, up to not more than 100 percent of the table amounts. Separation of control areas is not required. The aggregate amount shall not exceed 80,000 pounds.
    d. “Low BV” Category 1B flammable gas has a burning velocity of 3.9 in/s (10 cm/s) or less.|For SI: 1 pound = 0.454 kg, 1 cubic foot = 0.028 m3.
    a. Control areas shall be separated from each other by not less than a 1-hour fire barrier.
    b. The building shall be equipped throughout with an approved automatic sprinkler system with a minimum sprinkler design density of Ordinary Hazard Group 2 in the area
    where flammable gases are stored or displayed.
    c. Where storage areas exceed 50,000 square feet in area, the maximum allowable quantities area is allowed to be increased by 2 percent for each 1,000 square feet of area in excess
    of 50,000 square feet, up to not more than 100 percent of the table amounts. Separation of control areas is not required. The aggregate amount shall not exceed 80,000 pounds.
    d. “Low BV” Category 1B flammable gas has a burning velocity of 3.9 in/s (10 cm/s) or less.|

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    HAZARDOUS MATERIALS—GENERAL PROVISIONS

    5003.11.2.1 Fire protection and storage arrangements. Fire protection and container storage arrangements for quantities of Category 1B flammable gases permitted by Table 5003.11.2 shall be in accordance with the all of the following:

    1. Storage of Category 1B flammable gases on shelves shall not exceed 6 feet (1829 mm) in height, and shelving shall be metal.
    2. Rack storage, pallet storage or piles of Category 1B flammable gas greater than 6 feet 6 inches (1981 mm) in height shall be provided with an automatic sprinkler system with a minimum design density of Extra Hazard Group 1.
    3. Combustible commodities shall not be stored above Category 1B flammable gases.
    4. Flammable liquids shall be separated from Category 1B flammable gases by a distance of not less than 20 feet (6096 mm).
  • CBC § 414.1.3 High relevance — show source text

    [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.

    [F] TABLE 414.2.2—DESIGN AND NUMBER OF CONTROL AREAS Col2 Col3 Col4 Col5
    STORY STORY PERCENTAGE OF THE MAXIMUM
    ALLOWABLE QUANTITY PER
    CONTROL AREAa    		 NUMBER OF CONTROL
    AREAS PER STORY    		 FIRE-RESISTANCE
    RATING FOR FIRE
    BARRIERS IN HOURSb
    Above grade plane Higher than 9 5 1 2
    Above grade plane 7−9 5 2 2
    Above grade plane 6 12.5 2 2
    Above grade plane 5 12.5 2 2
    Above grade plane 4 12.5 2 2
    Above grade plane 3 50 2 1
    Above grade plane 2 75 3 1
    Above grade plane 1 100 4 1
    Below grade plane 1 75 3 1
    Below grade plane 2 50 2 1
    Below grade plane Lower than 2 Not Allowed Not Allowed Not Allowed
    a. Percentages shall be of the maximum allowable quantity per control area shown in Tables 307.1(1) and 307.1(2), with all increases allowed in the notes to those tables.
    b. Separation shall include fire barriers and horizontal assemblies as necessary to provide separation from other portions of the building.    		 a. Percentages shall be of the maximum allowable quantity per control area shown in Tables 307.1(1) and 307.1(2), with all increases allowed in the notes to those tables.
    b. Separation shall include fire barriers and horizontal assemblies as necessary to provide separation from other portions of the building.    		 a.
  • CBC § 414.1 Medium 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 § 904.7 Medium relevance — show source text

    Foam systems 904.7 Glazing 2406, 2408.2.1 Halon systems 904.9 Personnel and material hoists 3004.4

    Roof tile 1504.3.1

    Seismic 1704.2

    Smoke control 909.3, 909.5.2, 909.10.2, 909.12.1, 909.13.3, 909.18, 909.20.7.3, 909.21.7, 1705.19 Soils1 803

    Sound transmission 1208 Sprinkler protection 903.5 Structural (see Special Inspections and Tests) Wet chemical systems 904.5 Testing Agency (definition) 202 Theaters [see Assembly Occupancy (Group A), Projection Rooms and Stages and Platforms] Thermal Barrier, Foam Plastic Insulation 2603.4, 2603.5.2 Thermal-insulating Materials (See Insulation) 712 Tile 202 Ceramic (see Ceramic Tile) Fire resistance, clay or shale 721.1 Tires, Bulk Storage of 311.2 Toddler 202 Toilets and Toilet Rooms Chapters 11A and 11B, 3305 Accessible 1127A, 1134A, 11B-213,

    1607.9.2

    Construction/finish materials 1210 Door locking 11B-404, Chapter 29 Family or assisted-use Chapters 11B and 29 Adult changing tables 11B-249 Fixture count Chapter 29 Grab bar live loads 1607.9.2 Location Chapter 29 Partitions 1210.3

    Privacy 1210.3 Public facilities Chapter 29 Signs Chapters 11A and 11B, 1143A Single user Chapter 29 Ventilation 1202.5.2.1

    Tornado 1603.1.4, 1609.5, 1609.6.3,

    1609.6.3.2 Tornado Shelter (see Storm Shelter)

    Towers Airport traffic control 412.2 Cooling 1511.4 Location and access 3108.2

    Radio 3108

    Television 3108

    Townhouses 101.2, 202

    Toxic Materials [see High-hazard Occupancy (Group H)] Classification 307.6, 414, 415 Gas detection system 415.11.7, 421.5, 908.3

    Transient 310.2, 310.4 Transient Lodging (definition) 202 Transportation 11B-810 Travel Distance Area of refuge 1009.6.1 Assembly seating 1030.7 Atrium 404.9 Balcony, exterior 1017.2.1 Care suites (Group I-2) 407.4.2, 407.4.4 Common path of travel 1006.2.1 Drinking fountains Chapter 29 Exit access 1017.2

    Mall 402.8.5, 402.8.6

Frequently asked questions

How do I know whether a control area is "sprinklered" for CBC allowances?

The CBC requires the building be equipped throughout with an approved automatic sprinkler system and, for some allowances, a minimum sprinkler design density (often Ordinary Hazard Group 2) in the area where the materials are stored or displayed; check the specific subsection (for example § 414.2.5.4) and the California Fire Code for the design criteria.

Can I just add sprinklers to increase allowable quantities?

Adding sprinklers can change the allowable quantities, but the sprinklers must meet the code’s required design, arrangement and whole‑building conditions (and the building must be “equipped throughout” as the subsection requires). Confirm the design density and approved system per the Fire Code before depending on the increase.

Where do I find the base maximum quantities that these percentages modify?

The percentages in Table 414.2.2 are applied to the maximum allowable quantities per control area in Tables 307.1(1) and 307.1(2) (including any increases allowed in those tables’ notes). See § 414.2 and Table 414.2.2.

Is the floor assembly always required to be 2 hours?

The floor assembly and supporting construction are generally required to be 2 hours, but an exception allows 1 hour in Types IIA, IIIA, IV and VA construction if the building is sprinklered per § 903.3.1.1 and is three stories or fewer above grade plane. See § 414.2.4.

Do I still need to submit documentation to the building official?

Yes. § 414.1.3 requires a report to the building official identifying maximum expected quantities, how you will meet protection methods (control areas, fire protection systems, Group H classification if needed), and that report must be prepared by a qualified person.

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When is a space classified as Group H (high-hazard)?

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Occupancy classification & control areas

California Building Code