Section 5004 — STORAGE

5004.1 Scope. ¶

Storage of hazardous materials in amounts exceeding the maximum allowable quantity per control area as set forth in Section 5003.1 shall be in accordance with Sections 5001, 5003 and 5004. Storage of hazardous materials in amounts not exceeding the maximum allowable quantity per control area as set forth in Section 5003.1 shall be in accordance with Sections 5001 and

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HAZARDOUS MATERIALS—GENERAL PROVISIONS

Retail and wholesale storage and display of nonflammable solid and nonflammable and noncombustible liquid hazardous materials in Group M occupancies and Group S storage shall be in accordance with Section 5003.11.

5004.2 Spill control and secondary containment for liquid and solid hazardous materials. ¶

Rooms, buildings or areas used for the storage of liquid or solid hazardous materials shall be provided with spill control and secondary containment in accordance with Sections 5004.2.1 through 5004.2.3.

Exception: Outdoor storage of containers on approved containment pallets in accordance with Section 5004.2.3.

5004.2.1 Spill control for hazardous material liquids. Rooms, buildings or areas used for the storage of hazardous material liquids in individual vessels having a capacity of more than 55 gallons (208 L), or in which the aggregate capacity of multiple vessels exceeds 1,000 gallons (3785 L), shall be provided with spill control to prevent the flow of liquids to adjoining areas. Floors in indoor locations and similar surfaces in outdoor locations shall be constructed to contain a spill from the largest single vessel by one of the following methods:

Liquid-tight sloped or recessed floors in indoor locations or similar areas in outdoor locations.
Liquid-tight floors in indoor locations or similar areas in outdoor locations provided with liquid-tight raised or recessed sills or dikes.
Sumps and collection systems.
Other approved engineered systems.

Except for surfacing, the floors, sills, dikes, sumps and collection systems shall be constructed of noncombustible material, and the liquid-tight seal shall be compatible with the material stored. Where liquid-tight sills or dikes are provided, they are not required at perimeter openings having an open-grate trench across the opening that connects to an approved collection system.

5004.2.2 Secondary containment for hazardous material liquids and solids. Where required by Table 5004.2.2, buildings, rooms or areas used for the storage of hazardous materials liquids or solids shall be provided with secondary containment in accordance with this section where the capacity of an individual vessel or the aggregate capacity of multiple vessels exceeds both of the following:

Liquids: Capacity of an individual vessel exceeds 55 gallons (208 L) or the aggregate capacity of multiple vessels exceeds 1,000 gallons (3785 L).
Solids: Capacity of an individual vessel exceeds 550 pounds (250 kg) or the aggregate capacity of multiple vessels exceeds 10,000 pounds (4540 kg).

f an individual vessel or the aggregate capacity of multiple vessels exceeds both of the following:

Liquids: Capacity of an individual vessel exceeds 55 gallons (208 L) or the aggregate capacity of multiple vessels exceeds 1,000 gallons (3785 L).
Solids: Capacity of an individual vessel exceeds 550 pounds (250 kg) or the aggregate capacity of multiple vessels exceeds 10,000 pounds (4540 kg).

TABLE 5004.2.2—REQUIRED SECONDARY CONTAINMENT—HAZARDOUS MATERIAL SOLIDS AND LIQUIDS STORAGE

MATERIAL	MATERIAL	INDOOR STORAGE	INDOOR STORAGE	OUTDOOR STORAGE	OUTDOOR STORAGE
MATERIAL	MATERIAL	Solids	Liquids	Solids	Liquids
1. Physical-hazard materials	1. Physical-hazard materials	1. Physical-hazard materials	1. Physical-hazard materials	1. Physical-hazard materials	1. Physical-hazard materials
Combustible liquids	Class II	Not Applicable	See Chapter 57	Not Applicable	See Chapter 57
Combustible liquids	Class IIIA	Class IIIA	See Chapter 57	See Chapter 57	See Chapter 57
Combustible liquids	Class IIIB	Class IIIB	See Chapter 57	See Chapter 57	See Chapter 57
Cryogenic fluids	Cryogenic fluids	Cryogenic fluids	See Chapter 55	See Chapter 55	See Chapter 55
Explosives	Explosives	See Chapter 56	See Chapter 56	See Chapter 56	See Chapter 56
Flammable liquids	Class IA	Not Applicable	See Chapter 57	Not Applicable	See Chapter 57
Flammable liquids	Class IB	Class IB	See Chapter 57	See Chapter 57	See Chapter 57
Flammable liquids	Class IC	Class IC	See Chapter 57	See Chapter 57	See Chapter 57
Flammable solids	Flammable solids	Not Required	Not Applicable	Not Required	Not Applicable
Organic peroxides	Unclassified Detonable	Required	Required	Not Required	Not Required
Organic peroxides	Class I	Class I	Class I	Class I	Class I
Organic peroxides	Class II	Class II	Class II	Class II	Class II
Organic peroxides	Class III	Class III	Class III	Class III	Class III
Organic peroxides	Class IV	Class IV	Class IV	Class IV	Class IV
Organic peroxides	Class V	Not Required	Not Required	Not Required	Not Required
Oxidizers	Class 4	Required	Required	Not Required	Not Required
Oxidizers	Class 3	Class 3	Class 3	Class 3	Class 3
Oxidizers	Class 2	Class 2	Class 2	Class 2	Class 2
Oxidizers	Class 1	Not Required	Not Required	Not Required	Not Required

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HAZARDOUS MATERIALS—GENERAL PROVISIONS

TABLE 5004.2.2—REQUIRED SECONDARY CONTAINMENT—HAZARDOUS MATERIAL SOLIDS AND LIQUIDS STORAGE—continued

MATERIAL	MATERIAL	INDOOR STORAGE	INDOOR STORAGE	OUTDOOR STORAGE	OUTDOOR STORAGE
MATERIAL	MATERIAL	Solids	Liquids	Solids	Liquids
Pyrophorics	Pyrophorics	Not Required	Required	Not Required	Required
Unstable (reactives)	Class 4	Required	Required	Required	Required
Unstable (reactives)	Class 3	Class 3	Class 3	Class 3	Class 3
Unstable (reactives)	Class 2	Class 2	Class 2	Class 2	Class 2
Unstable (reactives)	Class 1	Not Required	Not Required	Not Required	Not Required
Water reactives	Class 3	Required	Required	Required	Required
Water reactives	Class 2	Class 2	Class 2	Class 2	Class 2
Water reactives	Class 1	Not Required	Not Required	Not Required	Not Required
2. Health-hazard materials	2. Health-hazard materials	2. Health-hazard materials	2. Health-hazard materials	2. Health-hazard materials	2. Health-hazard materials
Corrosives	Corrosives	Not Required	Required	Not Required	Required
Highly toxics	Highly toxics	Required	Required	Required	Required
Toxics	Toxics	Toxics	Toxics	Toxics	Toxics

5004.2.2.1 Containment and drainage methods. The building, room or area shall contain or drain the hazardous materials and fire protection water through the use of one of the following methods:

Liquid-tight sloped or recessed floors in indoor locations or similar areas in outdoor locations.
Liquid-tight floors in indoor locations or similar areas in outdoor locations provided with liquid-tight raised or recessed sills or dikes.
Sumps and collection systems.
Drainage systems leading to an approved location.
Other approved engineered systems.

5004.2.2.2 Incompatible materials. Incompatible materials used in open systems shall be separated from each other in the secondary containment system.

5004.2.2.3 Indoor design. Secondary containment for indoor storage areas shall be designed to contain a spill from the largest vessel plus the design flow volume of fire protection water calculated to discharge from the fire-extinguishing system over the minimum required system design area or area of the room or area in which the storage is located, whichever is smaller. The containment capacity shall be designed to contain the flow for a period of 20 minutes.

5004.2.2.4 Outdoor design. Secondary containment for outdoor storage areas shall be designed to contain a spill from the largest individual vessel. If the area is open to rainfall, secondary containment shall be designed to include the volume of a 24hour rainfall as determined by a 25-year storm and provisions shall be made to drain accumulations of groundwater and rainwater.

5004.2.2.5 Monitoring. An approved monitoring method shall be provided to detect hazardous materials in the secondary containment system. The monitoring method is allowed to be visual inspection of the primary or secondary containment, or other approved means. Where secondary containment is subject to the intrusion of water, a monitoring method for detecting water shall be provided. Where monitoring devices are provided, they shall be connected to approved visual or audible alarms.

5004.2.2.6 Drainage system design. Drainage systems shall be in accordance with the California Plumbing Code and all of the following:

The slope of floors to drains in indoor locations, or similar areas in outdoor locations shall be not less than 1 percent.
Drains from indoor storage areas shall be sized to carry the volume of the fire protection water as determined by the design density discharged from the automatic fire-extinguishing system over the minimum required system design area or area of the room or area in which the storage is located, whichever is smaller.
Drains from outdoor storage areas shall be sized to carry the volume of the fire flow and the volume of a 24-hour rainfall as determined by a 25-year storm.
Materials of construction for drainage systems shall be compatible with the materials stored.
Incompatible materials used in open systems shall be separated from each other in the drainage system.
Drains shall terminate in an approved location away from buildings, valves, means of egress, fire access roadways, adjoining property and storm drains.

5004.2.3 Containment pallets. Where used as an alternative to spill control and secondary containment for outdoor storage in accordance with the exception in Section 5004.2, containment pallets shall comply with all of the following:

A liquid-tight sump with access for visual inspection shall be provided.
The sump shall be designed to contain not less than 66 gallons (250 L).

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HAZARDOUS MATERIALS—GENERAL PROVISIONS

Exposed surfaces shall be compatible with material stored.
Containment pallets shall be protected to prevent collection of rainwater within the sump.

5004.3 Ventilation. ¶

Indoor storage areas and storage buildings shall be provided with mechanical exhaust ventilation or natural ventilation where natural ventilation can be shown to be acceptable for the materials as stored.

Exceptions:

Storage areas for flammable solids complying with Chapter 59.
Storage areas for medical gases complying with Chapter 53.

5004.3.1 System requirements. Exhaust ventilation systems shall comply with all of the following:

Installation shall be in accordance with the California Mechanical Code .
Mechanical ventilation shall be at a rate of not less than 1 cubic foot per minute per square foot [0.00508 m [3] /(s × m [2] )] of floor area over the storage area.
Systems shall operate continuously unless alternative designs are approved.
A manual shutoff control shall be provided outside of the room in a position adjacent to the access door to the room or in an approved location. The switch shall be a break-glass or other approved type and shall be labeled: “VENTILATION SYSTEM EMERGENCY SHUTOFF.”

Exception: [For SFM] When exhaust systems containing explosive, corrosive, combustible, flammable or highly toxic dusts, mists, fumes, vapors or gases are 100 percent exhausted to the outside, an emergency ventilation system shutoff is not required. 5. Exhaust ventilation shall be designed to consider the density of the potential fumes or vapors released. For fumes or vapors that are heavier than air, exhaust shall be taken from a point within 12 inches (305 mm) of the floor. For fumes or vapors that are lighter than air, exhaust shall be taken from a point within 12 inches (305 mm) of the highest point of the

room.

The location of both the exhaust and inlet air openings shall be designed to provide air movement across all portions of the floor or room to prevent the accumulation of vapors.
Exhaust air shall not be recirculated to occupied areas if the materials stored are capable of emitting hazardous vapors and contaminants have not been removed. Air contaminated with explosive or flammable vapors, fumes or dusts; flammable, highly toxic or toxic gases; or radioactive materials shall not be recirculated.

5004.4 Separation of incompatible hazardous materials. ¶

Incompatible materials shall be separated in accordance with Section 5003.9.8.

5004.5 Automatic sprinkler systems. ¶

Indoor storage areas and storage buildings shall be equipped throughout with an approved automatic sprinkler system in accordance with Section 903.3.1.1. The design of the sprinkler system shall be not less than that required for Ordinary Hazard Group 2 with a minimum design area of 3,000 square feet (279 m [2] ). Where the materials or storage arrangement are required by other regulations to be provided with a higher level of sprinkler system protection, the higher level of sprinkler system protection shall be provided.

5004.6 Explosion control. ¶

Indoor storage rooms, areas and buildings shall be provided with explosion control in accordance with Section 911.

5004.7 Standby or emergency power. ¶

Where mechanical ventilation, treatment systems, temperature control, alarm, detection or other electrically operated systems are required, such systems shall be provided with an emergency or standby power in accordance with Section 1203.

For storage areas for highly toxic or toxic materials, see Sections 6004.2.2.8 and 6004.3.4.2.

5004.7.1 Exempt applications. Standby or emergency power is not required for mechanical ventilation systems for any of the following:

Storage of Class IB and IC flammable liquids and Class II and III combustible liquids in closed containers not exceeding a capacity of 6 [1] / 2 gallons (25 L).
Storage of Class 1 and 2 oxidizers.
Storage of Class II, III, IV and V organic peroxides.
Storage of asphyxiant, irritant and radioactive gases.

5004.7.2 Fail-safe engineered systems. Standby power for mechanical ventilation, treatment systems and temperature control systems shall not be required where an approved fail-safe engineered system is installed.

5004.8 Limit controls. ¶

Limit controls shall be provided in accordance with Sections 5004.8.1 and 5004.8.2.

5004.8.1 Temperature control. Materials that must be kept at temperatures other than normal ambient temperatures to prevent a hazardous reaction shall be provided with an approved means to maintain the temperature within a safe range. Redundant temperature control equipment that will operate on failure of the primary temperature control system shall be provided. Where approved, alternative means that prevent a hazardous reaction are allowed.

5004.8.2 Pressure control. Stationary tanks and equipment containing hazardous material liquids that can generate pressures exceeding design limits because of exposure fires or internal reaction shall have some form of construction or other approved means that will relieve excessive internal pressure. The means of pressure relief shall vent to an approved location or to an exhaust scrubber or treatment system where required by Chapter 60.

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HAZARDOUS MATERIALS—GENERAL PROVISIONS

5004.9 Emergency alarm. ¶

An approved manual emergency alarm system shall be provided in buildings, rooms or areas used for storage of hazardous materials. Emergency alarm-initiating devices shall be installed outside of each interior exit or exit access door of storage buildings, rooms or areas. Activation of an emergency alarm-initiating device shall sound a local alarm to alert occupants of an emergency situation involving hazardous materials.

5004.10 Supervision and monitoring. ¶

Emergency alarm, detection and automatic fire-extinguishing systems required by Section 5004 shall be electrically supervised and monitored by an approved supervising station or, where approved, shall initiate an audible and visual signal at a constantly attended on-site location.

5004.11 Clearance from combustibles. ¶

The area surrounding an outdoor storage area or tank shall be kept clear of combustible materials and vegetation for a minimum distance of 25 feet (7620 mm).

5004.12 Noncombustible floor. ¶

Except for surfacing, floors of storage areas shall be of noncombustible construction.

5004.13 Weather protection. ¶

Where overhead noncombustible construction is provided for sheltering outdoor hazardous material storage areas, such storage shall not be considered indoor storage where the area is constructed in accordance with the requirements for weather protection as required by the California Building Code .

Exception: Storage of explosive materials shall be considered as indoor storage.

5004.14 Outdoor storage location. ¶

Outdoor storage areas for hazardous materials shall be located as required by Section 5003.12 except where material-specific requirements, including requirements in referenced standards, are provided in other chapters of this code.