ICC Subscriptions
 
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 International Fire Code. Hazardous materials stored, or used on top of roofs or canopies shall be classified as outdoor storage or use and shall comply with the International Fire Code. [F]

Exceptions: The following shall not be classified as Group H, but shall be classified as the occupancy that they most nearly resemble.

1. Buildings and structures occupied for the application of flammable finishes, provided that such buildings or areas conform to the requirements of Section 416 and the International Fire Code.
2. Wholesale and retail sales and storage of flammable and combustible liquids in mercantile occupancies conforming to the International Fire Code.
3. Closed piping system containing flammable or combustible liquids or gases utilized for the operation of machinery or equipment.
4. Cleaning establishments that utilize combustible liquid solvents having a flash point of 140°F (60°C) or higher in closed systems employing equipment listed by an approved testing agency, provided that this occupancy is separated from all other areas of the building by 1-hour fire barriers constructed in accordance with Section 707 or 1-hour horizontal assemblies constructed in accordance with Section 712, or both.
5. Cleaning establishments that utilize a liquid solvent having a flash point at or above 200°F (93°C).
6. Liquor stores and distributors without bulk storage.
7. Refrigeration systems.
8. The storage or utilization of materials for agricultural purposes on the premises.
9. Stationary batteries utilized for facility emergency power, uninterrupted power supply or telecommunication facilities, provided that the batteries are provided with safety venting caps and ventilation is provided in accordance with the International Mechanical Code.
10. Corrosives shall not include personal or household products in their original packaging used in retail display or commonly used building materials.
11. Buildings and structures occupied for aerosol storage shall be classified as Group S-1, provided that such buildings conform to the requirements of the International Fire Code.
12. Display and storage of nonflammable solid and nonflammable or noncombustible liquid hazardous materials in quantities not exceeding the maximum allowable quantity per control area in Group M or S occupancies complying with Section 414.2.5.
13. The storage of black powder, smokeless propellant and small arms primers in Groups M and R-3 and special industrial explosive devices in Groups B, F, M and S, provided such storage conforms to the quantity limits and requirements prescribed in the International Fire Code.


This section identifies the various types of facilities contained in the high-hazard occupancy. This occupancy classification relates to those facilities where the storage of materials or the operations are deemed to be extremely hazardous to life and property, especially when they involve the use of significant amounts of highly combustible, flammable or explosive materials, regardless of their composition (i.e., solids, liquids, gases or dust). Although they are not explosive or highly flammable, other hazardous materials, such as corrosive liquids, highly toxic materials and poisonous gases, still present an extreme hazard to life. Many materials possess multiple hazards, whether physical or health related.

There is a wide range of high-hazard operations in the industrial community; therefore, it is more practical to categorize such facilities in terms of the degree of hazard they present, rather than attempt to define a facility in terms of its function. This method is similar to that used to categorize factory (see Section 306) and storage (see Section 311) occupancies.

Group H is handled as a separate classification because it represents an unusually high degree of hazard that is not found in the other occupancies. It is important to isolate those industrial or storage operations that pose the greatest dangers to life and property and to reduce such hazards by providing systems or elements of protection through the regulatory provisions of building codes.

There are numerous provisions and exceptions throughout the code that cannot be used when one or more Group H occupancies are present.

Operations that, because of the materials utilized or stored, cause a building or portion of a building to be classified as a high-hazard occupancy are identified in this section. While buildings classified as Group H may not have a large occupant load, the unstable chemical properties of the materials contained on the premises constitute an above-average fuel load and serve as a potential danger to the surrounding area.

The dangers created by the high-hazard materials require special consideration for the abatement of the danger. The classification of a material as high hazard is based on information derived from National Fire Protection Association (NFPA) standards and the Code of Federal Regulations (DOL 29 CFR).

The wide range of materials utilized or stored in buildings creates an equally wide range of hazards to the occupants of the building, the building proper and the surrounding area. Since these hazards range from explosive to corrosive conditions, the high-hazard occupancy has been broken into four subclassifications: Groups H-1 through H-4. A fifth category, Group H-5, is used to represent structures that contain hazardous production material (HPM) facilities. Each of these subclassifications addresses materials that have similar characteristics and the protection requirements attempt to address the hazard involved. These subclassifications are defined by the properties of the materials involved with only occasional reference to specific materials. This performance-based criterion may involve additional research to identify a hazard, but it is the only way to remain current in a rapidly changing field. Material Safety Data Sheets (MSDS) will be a major source for information.

Additional information on hazardous materials can be found in Section 415 as well as the commentary to the International Fire Code® (IFC®).

Section 307.1 acknowledges that a building is not classified as a high-hazard occupancy unless the maximum allowable quantities per control area as prescribed in Tables 307.1(1) and 307.1(2) are exceeded, subject to the applicable control area provisions of Section 414.2. The maximum quantity limitations per control area prescribed in Tables 307.1(1) and 307.1(2) have been determined to be relatively safe when maintained in accordance with the IFC. Therefore, a building containing less than the maximum allowable quantities specified in Tables 307.1(1) and 307.1(2) would not be classified as a Group H occupancy but rather as the occupancy group it most nearly resembles.

Section 414.2 establishes the control area concept for regulating hazardous materials. This concept would allow the maximum allowable quantities of hazardous materials per control area in Tables 307.1(1) and 307.1(2) to be exceeded within a given building without classifying the building as a high-hazard occupancy by utilizing a multiple control area approach. The permitted number of control areas, maximum percentage of allowable quantities of hazardous materials per control area and degree of fire separation between control areas is regulated by Section 414.2 (see commentary, Section 414.2).

Section 307.1 also clarifies that hazardous materials outside of the building envelope should be classified as outdoor storage. As such, hazardous material quantities on roofs or canopies are not included in evaluating the occupancy classification of a building or structure. Canopies used to support gaseous hydrogen systems must comply with Section 406.5.3.1.

The exceptions list conditions that are exempt from a high-hazard classification because of the building's construction or use, the packaging of materials, the quantity of materials or the precautions taken to prevent fire. Even if a high-hazard material meets one of the exceptions, its storage and use must comply with the applicable provisions of Section 414 and the IFC.

Exception 1 exempts spray painting and similar operations within buildings from being classified as a high-hazard occupancy. This exception requires that all such operations, as well as the handling of flammable finishes, are in accordance with the provisions of Section 416 and the IFC; therefore, an adequately protected typical paint spray booth in a factory (Group F-1) would not result in a high-hazard occupancy classification for either the building or the paint spray area.

Exception 2 relies on the provisions of Section 3404.3.4.1 of the IFC to regulate the storage of flammable and combustible liquids for wholesale and retail sales and storage in mercantile occupancies. The overall permitted amount of flammable and combustible liquids is dependent on the class of liquid, storage arrangement, container size and level of sprinkler protection. For nonsprinklered buildings, the maximum allowable quantity per control area permitted by Table 3404.3.4.1 of the IFC is 1,600 gallons (6057 L) of Class IB, IC, II, and IIIA liquids with a maximum of 60 gallons (227 L) of Class IA liquids. Depending on storage and ceiling heights, buildings equipped with a sprinkler system with a minimum design density for an Ordinary Hazard Group 2 occupancy may have an aggregate total of 7,500 gallons (28 391 L) of Class IB, IC, II, and IIIA liquids with a maximum of 60 gallons (227 L) of Class IA liquids. The quantities of Class IB, IC, II and IIA liquids could be further increased depending on the potential storage conditions and enhanced degree of sprinkler protection. (See Section 3403.4.3.1 of the IFC for additional design information.) Again, it should be noted, that despite the increased quantities which far exceed the base quantity limitations of Table 307.1(1), compliance with this exception would result in the building not being classified as a Group H occupancy.

Exception 3 exempts closed systems that are used exclusively for the operation of machinery or equipment. The closed piping systems, which are essentially not open to the atmosphere, keep flammable or combustible liquids from direct exposure to external sources of ignition as well as prevent the users from coming in direct contact with liquids or harmful vapors. This exception would include systems such as oil-burning equipment, piping for diesel fuel generators and LP-gas cylinders for use in forklift trucks.

Exception 4 exempts cleaning establishments that utilize a closed system for all combustible liquid solvents with a flash point at or above 140°F (60°C). The reference to using equipment listed by an approved testing laboratory does not mean that the entire system needs to be approved, but rather the individual pieces of equipment. As with any mechanical equipment or appliance, it should bear the label of an approved agency and be installed in accordance with the manufacturer's installation instructions [see the International Mechanical Code® (IMC®)].

Exception 5 covers cleaning establishments that use solvents that have very high flash points [at least 200°F (93°C)] and that are exceedingly difficult to ignite. Such liquids can be used openly, but with due care.

Exception 6 exempts all retail liquor stores and liquor distribution facilities from the high-hazard occupancy classification, even though most of the contents are considered combustible liquids. The exception takes into account that alcoholic beverages are packaged in individual containers of limited size.

Exception 7 refers to refrigeration systems that utilize refrigerants that may be flammable or toxic Refrigeration systems do not alter the occupancy classification of the building, provided they are installed in accordance with the IMC. The IMC has specific limitations on the quantity and type of refrigerants that can be used, depending on the occupancy classification of the building.

Exception 8 exempts materials that are used for agricultural purposes, such as fertilizers, pesticides, fungicides, etc., when used on the premises. Agricultural materials stored for direct or immediate use are not usually of such quantities that would constitute a large fuel load or an exceptionally hazardous condition.

Exception 9 addresses battery storage rooms when used as part of an operating system, such as for providing standby power. The batteries used in installations of this type do not represent a significant health, safety or fire hazard. The electrolyte and battery casing contribute little fuel load to a fire. The release of hydrogen gas during the operation of battery systems is minimal. Ventilation in accordance with the IMC will disperse the small amounts of liberated hydrogen. This exception also assumes that rooms containing stationary storage battery systems are in compliance with Section 608 of the IFC.

Without Exception 10 certain products that technically are corrosive could cause grocery stores and other mercantile occupancies to be inappropriately classified as Group H-4. This exception allows the maximum allowable quantity per control area in Table 307.1(2) for corrosives to be exceeded in the retail display area. This would include such things as bleaches, detergents and other household cleaning supplies in normal-size containers. The exception also exempts the storage or manufacture of commonly used building materials, such as portland cement, from being inappropriately classified as Group H.

Exception 11 exempts buildings and structures used for the storage of aerosol products, provided they are protected in accordance with the provisions of NFPA 30B and the IFC. The aerosol storage requirements in the IFC, referred to in this exception, are based on the provisions of NFPA 30B. Compliance with the exception exempts buildings from complying with the code provisions for Group H, provided the storage of aerosol products comply with the applicable separation, storage limitations and sprinkler design requirements specified in the IFC and NFPA 30B.

Exception 12 permits certain products found in mercantile and storage occupancies, which may be comprised of hazardous materials, to exceed the maximum allowable quantity per control area of Tables 307.1(1) and 307.1(2). The products, however, must be comprised of nonflammable solids or liquids that are nonflammable or noncombustible. Materials could include swimming pool chemicals, which are typically Class 2 or 3 oxidizers or industrial corrosive cleaning agents (see commentary, Section 414.2.5).

Exception 13 permits the base maximum allowable quantity per control area of black powder, smokeless propellant and small arms primers in Group M and R-3 occupancies to be exceeded, provided the material is stored in accordance with Chapter 33 of the IFC. The requirements are based on the provisions in NFPA 495. Similarly, special industrial explosive devices are found in a number of occupancies other than Group H (Groups B, F, M and S). Storage of these devices in accordance with the IFC is not required to have a high-hazard occupancy classification. Power drivers are commonly used in the construction industry, and there are stocks of these materials maintained for sale and use by the trade. The automotive airbag industry has evolved with the use of these devices, and they are located in automotive dealerships and personal use vehicles throughout society. The IFC currently exempts up to 50 pounds (23 kg) of these materials from regulation under Chapter 33 (explosives).



TABLE 307.1(1) MAXIMUM ALLOWABLE QUANTITY PER CONTROL AREA OF HAZARDOUS MATERIALS POSING A PHYSICAL HAZARDa, j, m, n, p [F]

MATERIAL
CLASS
GROUP WHEN THE MAXIMUM ALLOWABLE QUANTITY IS EXCEEDED
STORAGEb
USE-CLOSED SYSTEMSb
USE-OPEN SYSTEMSb
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 liquidc, i
II
IIIA
IIIB
H-2 or H-3
H-2 or H-3
N/A
N/A
120d, e
330d, e
13,200
e, f
N/A
N/A
120d
330d
13,200
f
N/A
N/A
30d
80d
3,300
f
Combustible fiber
Loose
Baled
o
H-3
(100)
(1,000)
N/A
N/A
(100)
(1,000)
N/A
N/A
(20)
(200)
N/A
Consumer fireworks
(Class C, Common)
1.4G
H-3
125d, e, l
N/A
N/A
N/A
N/A
N/A
N/A
N/A
Cryogenics, flammable
N/A
H-2
N/A
45d
N/A
N/A
45d
N/A
N/A
10d
Cryogenics, inert
N/A
N/A
N/A
N/A
NL
N/A
N/A
NL
N/A
N/A
Cryogenics, oxidizing
N/A
H-3
N/A
45d
N/A
N/A
45d
N/A
N/A
10d
Explosives
Division 1.1
Division 1.2
Division 1.3
Division 1.4
Division 1.4G
Division 1.5
Division 1.6
H-1
H-1
H-1 or H-2
H-3
H-3
H-1
H-1
1e, g
1e, g
5e, g
50e, g
125d, e, l
1e, g
1
d, e, g
(1)e, g
(1)e, g
(5)e, g
(50)e, g
N/A
(1)e, g
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
0.25g
0.25g
1g
50g
N/A
0.25g
N/A
(0.25)g
(0.25)g
(1)g
(50)g
N/A
(0.25)g
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
0.25g
0.25g
1g
N/A
N/A
0.25g
N/A
(0.25)g
(0.25)g
(1)g
N/A
N/A
(0.25)g
N/A
Flammable gas
Gaseous Liquefied
H-2
N/A
N/A
(150)
d,e
1,000d,e
N/A
N/A
N/A
(150)
d,e
1,000d,e
N/A
N/A
N/A
Flammable liquidc
1A
1B and 1C
H-2
or H-3
N/A
30d, e
120
d, e
N/A
N/A
30d
120
d
N/A
N/A
10d
30
d
Flammable liquid, combination
(1A, 1B, 1C)
N/A
H-2
or H-3
N/A
120d, e, h
N/A
N/A
120d, h
N/A
N/A
30d, h
Flammable solid
N/A
H-3
125d, e
N/A
N/A
125d
N/A
N/A
25d
N/A
Inert gas
Gaseous
Liquefied
N/A
N/A
N/A
N/A
N/A
N/A
NL
NL
N/A
N/A
N/A
N/A
NL
NL
N/A
N/A
N/A
N/A
Organic peroxide
UD
I
II
III
IV
V
H-1
H-2
H-3
H-3
N/A
N/A
1e, g
5d, e
50d, e
125d, e
NL
NL
(1)e, g
(5)d, e
(50)d, e
(125)d, e
NL
NL
N/A
N/A
N/A
N/A
N/A
N/A
0.25g
1d
50d
125d
NL
NL
(0.25)g
(1)
(50)d
(125)d
NL
NL
N/A
N/A
N/A
N/A
N/A
N/A
0.25g
1d
10d
25d
NL
NL
(0.25)g
(1)d
(10)d
(25)d
NL
NL
Oxidizer
4
3k
2
1
H-1
H-2 or H-3
H-3
N/A
1e, g
10d, e
250d, e
4,000
e, f
(1)e, g
(10)d, e
(250)d, e
(4,000)
e, f
N/A
N/A
N/A
N/A
0.25g
2d
250d
4,000
f
(0.25)g
(2)d
(250)d
(4,000)
f
N/A
N/A
N/A
N/A
0.25g
2d
50d
1,000
f
(0.25)g
(2)d
(50)d
(1,000)
f


TABLE 307.1(1)-continued-MAXIMUM ALLOWABLE QUANTITY PER CONTROL AREA OF HAZARDOUS MATERIALS POSING A PHYSICAL HAZARDa, j, m, n, p [F]

MATERIAL

CLASS
GROUP WHEN THE MAXIMUM ALLOWABLE QUANTITY IS EXCEEDED
STORAGEb
USE-CLOSED SYSTEMSb
USE-OPEN SYSTEMSb
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)
Oxidizing gas
Gaseous Liquefied
H-3
N/A
N/A
N/A
(150)
d,e
1,500d,e
N/A
N/A
N/A
N/A
(150)
d,e
1,500d,e
N/A
N/A
N/A
N/A
N/A
Pyrophoric material
N/A
H-2
4e, g
(4)e, g
50e, g
1g
(1)g
10g
0
0
Unstable (reactive)
4
3
2
1
H-1
H-1 or H-2
H-3
N/A
1e, g
5d, e
50d, e
NL
(1)e, g
(5)d, e
(50)d, e
NL
10g
50d, e
250d, e
NL
0.25g
1d
50d
NL
(0.25)g
(1)d
(50)d
NL
2e, g
10d, e
250d, e
NL
0.25g
1d
10d
NL
(0.25)g
(1)d
(10)d
NL
Water reactive
3
2
1
H-2
H-3
N/A
5d, e
50d, e
NL
(5)d, e
(50)d, e
NL
N/A
N/A
N/A
5d
50d
NL
(5)d
(50)d
NL
N/A
N/A
N/A
1d
10d
NL
(1)d
(10)d
NL


For SI: 1 cubic foot = 0.028 m3, 1 pound = 0.454 kg, 1 gallon = 3.785 L.

NL = Not Limited; N/A = Not Applicable; UD = Unclassified Detonable

a. For use of control areas, see Section 414.2.

b. The aggregate quantity in use and storage shall not exceed the quantity listed for storage.

c. The quantities of alcoholic beverages in retail and wholesale sales occupancies shall not be limited providing the liquids are packaged in individual containers not exceeding 1.3 gallons. In retail and wholesale sales occupancies, the quantities of medicines, foodstuffs, consumer or industrial products, and cosmetics containing not more than 50 percent by volume of water-miscible liquids with the remainder of the solutions not being flammable, shall not be limited, provided that such materials are packaged in individual containers not exceeding 1.3 gallons.

d. Maximum allowable quantities shall be increased 100 percent in buildings equipped throughout with an automatic sprinkler system in accordance with Section 903.3.1.1. Where Note e also applies, the increase for both notes shall be applied accumulatively.

e. Maximum allowable quantities shall be increased 100 percent when stored in approved storage cabinets, day boxes, gas cabinets or exhausted enclosures or in listed safety cans in accordance with Section 2703.9.10 of the International Fire Code. Where Note d also applies, the increase for both notes shall be applied accumulatively.

f. 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.

g. Permitted only in buildings equipped throughout with an automatic sprinkler system in accordance with Section 903.3.1.1.

h. Containing not more than the maximum allowable quantity per control area of Class IA, IB or IC flammable liquids.

i. The maximum allowable quantity shall not apply to fuel oil storage complying with Section 603.3.2 of the International Fire Code.

j. Quantities in parenthesis indicate quantity units in parenthesis at the head of each column.

k. A maximum quantity of 200 pounds of solid or 20 gallons of liquid Class 3 oxidizers is allowed when such materials are necessary for maintenance purposes, operation or sanitation of equipment. Storage containers and the manner of storage shall be approved.

l. Net weight of the pyrotechnic composition of the fireworks. Where the net weight of the pyrotechnic composition of the fireworks is not known, 25 percent of the gross weight of the fireworks, including packaging, shall be used.

m. For gallons of liquids, divide the amount in pounds by 10 in accordance with Section 2703.1.2 of the International Fire Code.

n. For storage and display quantities in Group M and storage quantities in Group S occupancies complying with Section 414.2.5, see Tables 414.2.5(1) and 414.2.5(2).

o. Densely packed baled cotton that complies with the packing requirements of ISO 8115 shall not be included in this material class.

p. The following shall not be included in determining the maximum allowable quantities:

1. Liquid or gaseous fuel in fuel tanks on vehicles.

2. Liquid or gaseous fuel in fuel tanks on motorized equipment operated in accordance with this code.

3. Gaseous fuels in piping systems and fixed appliances regulated by the International Fuel Gas Code.

4. Liquid fuels in piping systems and fixed appliances regulated by the International Mechanical Code.



The maximum allowable quantities of high-hazard materials allowed in each control area before having to classify a part of the (or the entire) building as a high-hazard occupancy are given in the table. This table is referenced in Section 307.1. The materials listed in this table are classified according to their specific occupancy in Sections 307.3 through 307.5 and defined in Section 307.2. This table only contains materials applicable to Groups H-1, H-2 and H-3. The maximum allowable quantities per control area for Group H-4 materials are listed in Table 307.1(2).

The presence of any one or more of the materials listed in Table 307.1(1) in an amount greater than allowed requires that the building or area in which the material is contained be classified as a Group H, high-hazard occupancy.

If a building or area contains only the materials listed in either Table 307.1(1) or 307.1(2) in the maximum allowable quantity per control area or less, then that building or area would not be classified as a Group H, high-hazard occupancy. The possible increase in overall danger that might exist should this occur because of the storage and use of incompatible materials is an issue that the code does not specifically address. In such situations, the building official can seek the advice of chemical engineers, fire protection engineers, fire service personnel or other experts in the use of hazardous materials. Based on their advice, the building official can deem the building a high-hazard occupancy.

The maximum allowable quantity per control area listed in Table 307.1(1) is based on the concept of control areas as further regulated in Section 414. The quantities listed apply per control area. While every building area also represents a single control area, a given building may have multiple control areas, provided that the allowable amount within each control area is not exceeded and adequate fire-resistance-rated separation is provided between control areas. As indicated in Section 307.1, a building that utilizes multiple control areas and complies with the applicable provisions of Section 414 is not classified as Group H. The number, degree of separation and location of control areas are indicated in Section 414.


Table 307.7(1) is subdivided based on whether the material is in storage or in use in a closed or open system. Definitions of both closed and open systems are found in Section 307.2. Within these subdivisions, the appropriate maximum allowable quantity per control area is listed in accordance with the physical state (solid, liquid or gas) of the material. A column for gas in open systems is not indicated because hazardous gaseous materials should not be allowed in a system that is continuously open to the atmosphere. While hazardous materials within a closed or open system are considered to be in use, Note b clearly indicates that the aggregate quantity of hazardous materials in use and storage within a given control area should not exceed the quantity listed in Table 307.7(1) for storage. Without Note c, many common alcoholic beverages and household products containing a negligible amount of a hazardous material could result in a Group M occupancy being classified as a high hazard. Note c recognizes the reduced hazard of the materials based on their water miscibility and limited container size.

Notes d and e of Table 307.1(1) are significant in that, for certain materials, the maximum allowable amount may be increased due to the use of approved hazardous material storage cabinets, where the building is fully protected by an automatic sprinkler system, or both. The notes are intended to be cumulative in that up to four times the base maximum quantity may be allowed per control area, if both sprinklered and in cabinets, without classifying the building as Group H. While the use of cabinets is not always a feasible or practical method of storage, they do provide additional protection to warrant an increase if provided. Construction requirements for hazardous material storage cabinets are contained in the IFC. Note that the use of day boxes, gas cabinets, exhausted enclosures or listed safety cans would allow the same increase as for cabinets. Listed safety cans, which are primarily intended for flammable and combustible liquids, must be in compliance with UL 30 when used to increase the maximum allowable quantities permitted by Table 307.1(1).

While classified as a hazardous material, the code recognizes the relative hazard of Class IIIB liquids as compared to that of other flammable and combustible liquids by establishing a base maximum allowable quantity per control area of 13,200 gallons (49 962 L). As indicated in Note f, the quantity of Class I oxidizers and Class IIIB liquids would not be limited, provided the building is fully sprinklered in accordance with NFPA 13. Since any building that exceeds this maximum amount would be required to be classified as Group H and these buildings are required to be sprinklered, the maximum allowable amount would then be unlimited. As such, a Group H classification would not be warranted. The hazard presented by Class I oxidizers is that they slightly increase the burning rate of combustible materials that they may come into contact with during a fire. Class IIIB combustible liquids have flash points at or above 200°F (93°C). Motor oil is a typical example of a Class IIIB combustible liquid.

Note g recognizes that the hazard presented by certain materials is such that they may be stored or used only inside buildings that are fully sprinklered.

Note h clarifies for the user that while there is a combination maximum allowable quantity for flammable liquids, no individual class of liquid (Class IA, IB or IC) may exceed its own individual maximum allowable quantity.

Note i is a specific exception for inside storage tanks of combustible liquids that are connected to a fuel-oil piping system in accordance with Section 603.3.2 of the IFC. This exception applies to most oil-fired stationary equipment, whether in industrial, commercial or residential occupancies. NFPA31 and NFPA37 provide further guidance on the type of installations this exception is intending to permit. This exception would permit fuel-oil storage tanks containing a maximum of 660 gallons (2498 L) of combustible liquids within a building without being classified as a Group H-3 occupancy. This quantity limitation could be further increased to 3,000 gallons (11 356 L) for combustible liquids stored in protected above-ground tanks in rooms protected by an automatic sprinkler system complying with NFPA 13.

Note k permits a larger amount of Class 3 oxidizers in a building when used for maintenance and health purposes. The quantities proposed are reasonable for occupancies such as the health care industry where Class 3 oxidizers are used for maintenance purposes, sterilization and sanitation of equipment and operation sanitation. The method used to store the oxidizers is subject to the evaluation and approval of the building official. Note k also provides consistency with Note k of Table 2703.1.1(1) of the IFC.

Note l clarifies that the 125 pounds (57 kg) of storage permitted for consumer fireworks represents the net weight of the pyrotechnic composition of the fireworks in a nonsprinklered building. This amount represents approximately 121/2 shipping cases (less than one and one-half pallet loads) of fireworks in a nonsprinklered storage condition. In cases where the net weight of the pyrotechnic composition of the fireworks is unknown, 25 percent of the gross weight of the fireworks is to be used. The gross weight is to include the weight of the packaging.

Note n provides an exception when the amount of hazardous material in storage and display in Group M and S occupancies meet the requirements of Section 414.2.5.

Note o clarifies that densely packed baled cotton is not considered a hazardous material when meeting the size and weight requirements of ISO 8115 and, as such, is not subject to the maximum allowable quantity per control area specified for combustible fibers.

Note p is added to clarify that vehicles with closed fuel systems should be treated no differently than machinery or equipment when considering the allowable quantities of materials within a building. This note also clarifies that the fuels contained within the fuel tanks of vehicles or motorized equipment are not to be considered when calculating the aggregate quantity of hazardous materials within a control area of a building. For example, when evaluating a parking garage with several hundred cars parked inside, the fuel tanks of vehicles are not counted. When motorized equipment, such as a floor buffer or forklift, is used, those fuels are not included as long as other code requirements are satisfied.



TABLE 307.1(2) MAXIMUM ALLOWABLE QUANTITY PER CONTROL AREA OF HAZARDOUS MATERIAL POSING A HEALTH HAZARDa, b, c, i [F]

MATERIAL
STORAGEd
USE-CLOSED SYSTEMSd
USE-OPEN SYSTEMSd
Solid pounds (cubic feet)
Liquid gallons (pounds)e, f
Gas (cubic feet at NTP)e
Solid poundse
Liquid gallons (pounds)e
Gas (cubic feet at NTP)e
Solid poundse
Liquid gallons (pounds)e
Corrosive
5,000
500
Gaseous 810f
Liquefied
(150)
h
5,000
500
Gaseous 810f
Liquefied
(150)
h
1,000
100
Highly toxic
10
(10)h
Gaseous 20g
Liquefied (4)
g,h
10
(10)i
Gaseous 20g
Liquefied (4)
g,h
3
(3)i
Toxic
500
(500)h
Gaseous 810f
Liquefied
(150)
f,h
500
(500)i
Gaseous 810f
Liquefied
(150)
f,h
125
(125)


For SI: 1 cubic foot = 0.028 m3, 1 pound = 0.454 kg, 1 gallon = 3.785 L.

a. For use of control areas, see Section 414.2.

b. In retail and wholesale sales occupancies, the quantities of medicines, foodstuffs, consumer or industrial products, and cosmetics, containing not more than 50 percent by volume of water-miscible liquids and with the remainder of the solutions not being flammable, shall not be limited, provided that such materials are packaged in individual containers not exceeding 1.3 gallons.

c. For storage and display quantities in Group M and storage quantities in Group S occupancies complying with Section 414.2.5, see Tables 414.2.5(1) and 414.2.5(2).

d. The aggregate quantity in use and storage shall not exceed the quantity listed for storage.

e. Maximum allowable quantities shall be increased 100 percent in buildings equipped throughout with an approved automatic sprinkler system in accordance with Section 903.3.1.1. Where Note f also applies, the increase for both notes shall be applied accumulatively.

f. Maximum allowable quantities shall be increased 100 percent when stored in approved storage cabinets, gas cabinets or exhausted enclosures as specified in the International Fire Code. Where Note e also applies, the increase for both notes shall be applied accumulatively.

g. Allowed only when stored in approved exhausted gas cabinets or exhausted enclosures as specified in the International Fire Code.

h. Quantities in parenthesis indicate quantity units in parenthesis at the head of each column.

i. For gallons of liquids, divide the amount in pounds by 10 in accordance with Section 2703.1.2 of the International Fire Code.



Table 307.1(2), similar to Table 307.1(1), specifies the maximum quantities of hazardous materials, liquids or chemicals allowed per control area before having to classify a part of the (or the entire) building as a high-hazard occupancy. Table 307.1(2), as referenced in Section 307.1, contains materials classified as Group H-4 in accordance with Section 307.6. While the materials listed in this table are considered health hazards, some materials may also possess physical hazard characteristics more indicative of materials classified as Group H-1, H-2 or H-3.

The maximum allowable quantities per control area listed in Table 307.1(2) are indicative of industry practice and assume the materials are properly stored and handled in accordance with the IFC. Group H-4 materials, while indeed hazardous, are primarily considered a handling problem and do not possess the same fire, explosion or reactivity hazard associated with other hazardous materials. The base maximum allowable quantity per control area of 810 cubic feet (23 m3) for gases that are either corrosive or toxic is based on a standard-size chlorine cylinder. The use of 150 pounds (68 kg) as the baseline quantity for liquefied corrosive and toxic gases is intended to be consistent with the philosophical approach to the same maximum quantity permitted for liquefied oxidizing gases in Table 307.1(1). The 150-pound (68 kg) limitation allows a single cylinder of chlorine, which could be considered both a corrosive and oxidizing gas, to not result in either a Group H-3 or H-4 occupancy classification.

Without Note b, many common household products containing a negligible amount of a hazardous material could result in a Group M occupancy being classified as a high hazard. Note b recognizes the reduced hazard of the materials based on their water miscibility and limited container size.

Note c provides an exception when the amount of hazardous material in storage and display in Group M and S occupancies meets the requirements of Section 414.2.5.

Note d clearly indicates that the aggregate quantity of hazardous materials in use and storage, within a given control area, cannot exceed the quantity listed in the table for storage. Notes e and f are identical to Notes d and e to Table 307.1(1) and allow up to four times the maximum allowed quantities. See the commentary for Notes d and e of Table 307.1(1).

Note g is significant in that, for certain materials, their hazard is so great that their maximum allowable quantity per control area may be stored in the building only when approved exhausted enclosures or gas cabinets are utilized.