307.1 High-Hazard Group H
High-Hazard Group H occupancy includes, among others, the use of a building or structure, or a portion there of, that involves the manufacturing, processing, generation or storage of materials that constitute a physical or health hazard quantities in excess of those found in Tables 307.7 (1) and 307.7 (2) (see also definition of “Control area”).
307.2 Definitions.
The following words and terms shall, for the purposes of this section and as used elsewhere in this code, have the meanings shown herein.
-- Aerosol:
A product that is dispensed from an aerosol container by a propellant. Aerosol products shall be classified by means of the calculation of their chemical heats of combustion and shall be designated Level 1,2, or 3.
Level 1 aerosol products.
Those with a total chemical heat of combustion
that is less than or equal to 8,600 British thermal units per pound (Btu/lb) (20 kJ/g).
Level 2 aerosol products.
Those with a total chemical heat of combustion that is greater than 8,600 Btu/lb (20 kJ/g), but less than or equal to 13,000 Btu/lb (30 kJ/g).
Level 3 aerosol products.
Those with a total chemical heat combustion
that is greater than 13,000 Btu/lb (30 kJ/g).
-- Aerosol Container:
A metal can or a glass or plastic bottle designed to dispense an aerosol. Metal cans shall be limited to a maximum size of 33.8 fluid ounces (1,000 ml). Glass or plastic bottles shall be limited to a maximum size of 4 fluid ounces (118 ml).
-- Barricade:
A structure that consists of a combination of walls, floor and roof, which is designed to withstand thee rapid release of energy in an explosion and which is fully confined, partially vented or fully vented; or other effective method of shielding from explosive materials by a natural or artificial barrier.
-- Artificial barricade:
An artificial mound or revetment a minimum thickness of 3 feet (914 mm).
-- Natural barricade:
Natural features of the ground, such as hills, or timber of sufficient density that the surrounding exposures that require protection cannot be seen from the magazine or building containing explosives when the trees are bare of leaves.
-- Boiling Point:
The temperature at which the vapor pressure of a liquid equals the atmospheric pressure of 14.7 pounds per square inch (psia) (101 kPa) gage or 760 mm of mercury. Where an accurate boiling point is unavailable for the material in question, or for mixtures which do not have a constant boiling point, for the purposes of this classification, the 20-percent evaporated point of a distillation performed in accordance with ASTM D 86 shall be used as the boiling point of the liquid.
-- Closed System:
The use of a solid or liquid hazardous material involving a closed vessel or system that remains closed during normal operations where vapors emitted by the products are not liberated outside of the vessel or system and the products is not exposed to the atmosphere during normal operations; and all uses of compressed gases. Examples of closed systems for solid and liquids include product conveyed through a piping system into a closed vessel, system or piece of equipment.
-- Combustible Dust:
Finely divided solid material that is 420 microns or less in diameter and which, when dispersed in air in the proper proportions, could be ignited by a flame, spark, or other source of ignition. Combustible dust will pass through a U.S. No. 40 standard sieve.
-- Combustible Fibers:
Readily ignitable and free-burning fibers, such as cocoa fiber, cloth, cotton, excelsior, hay, hemp, henequen, istle, jute, kapok, oakum, rags, sisal, Spanish moss, straw, tow, wastepaper, certain synthetic fiber or other materials.
-- Combustible Liquid:
A liquid having a closed cup flash point at or above 100 degrees F (38 degrees C). Combustible liquids shall be subdivided as follows:
Class II.
Liquids having a closed cup flash point at or above 100 degrees F (38 degrees C) and below 140 degrees F (60 degrees C).
Class IIIA.
Liquids having a closed cup flash point at or above 140 degrees F (60 degrees C) and below 200 degrees F (93 degrees C).
Class IIIB.
Liquids having a closed cup flash point at or above 200 degrees F (93 degrees C).
The category of combustible liquids does not include compressed gases or cryogenic fluids.
-- Compressed Gas:
A material, or mixture of materials which:
1. Is a gas at 68 degrees F (20 degrees C) or less at 14.7 pounds per square inch atmosphere (psia) (101 kPa) of pressure; and
2. Has a boiling pint of 68 degrees F (20 degrees C) or less at 14.7 psia (101 kPa) which is either liquefied, non-liquefied or in solution, except those gases which have no other health-or physical-hazard properties are not considered to be compressed until the pressure in the packaging exceeds 41 psia (282 kPa) at 68 degrees F (20 degrees C).
The states of a compressed gas are categorized as follows:
1. Non-liquefied compressed gases are gases, other than those in solution, which are in a packaging under the charged pressure and are entirely gaseous at a temperature of 68 degrees F (20 degrees C).
2. Liquefied compressed gases are gases that, in a packaging under the charged pressure, are partially liquid at a temperature of 68 degrees F (20 degrees C).
3. Compressed gases in solution are non-liquefied gases that are dissolved in a solvent.
4. Compressed gas mixtures consist of a mixture of tow or more compressed gases contained in a packaging, the hazard properties of which are represented by the properties of the mixture as a whole.
-- Control Area:
Spaces within a building that are enclosed and bounded by exterior walls, firewalls, fire barriers and roofs, or a combination thereof, where quantities of hazardous materials not exceeding the maximum allowable quantities per control area are stored, dispensed, used or handled.
-- Corrosive:
A chemical that causes visible destruction of, or irreversible alterations in, living tissue by chemical action at the point of contact. A chemical shall be considered corrosive if, when tested on the intact skin of albino rabbits by the method described in DOTn49 CFR, Part 173.137, such a chemical destroys or changes irreversibly the structure of the tissue at the point of contact following an exposure period of 4 hours. This tem does not refer to action on inanimate surfaces.
-- Cryogenic Fluid:
A liquid having a boiling point lower than –150 degrees F (-101 degrees C) at 14.7 pounds per square inch atmosphere (psia) (an absolute pressure of 101 kPa).
-- Deflagration:
An exothermic reaction, such as the extremely rapid oxidation of a flammable dust or vapor in air, in which the reaction progresses through the unburned material at a rate less than the velocity of sound. A deflagration can have an explosive effect.
-- Detached Building:
A separate single-story building, without a basement or crawl space, used for the storage or use of hazardous materials and located an approved distance from all structures.
-- Detonation:
An exothermic reaction characterized by the presence of a shock wave in the material which established and maintains the reaction. The reaction zone progresses through the material at a rate greater than the velocity of sound. The principal heating mechanism is one of shock compression. Detonations have an explosive effect.
-- Dispensing:
The pouring or transferring any material from a container, tank or similar vessel, whereby vapors, dusts, fumes, mists or gases are liberated to the atmosphere.
-- Explosive:
Any chemical compound, mixture or device, the primary or common purpose of which is to function by explosion. The term includes, but is not limited to, dynamite, black powder, pellet powder, initiating explosives, detonators, safety fuses, squibs, detonating cord, igniter cord, igniters and display fireworks, 1.3G (Class B, Special).
The term “explosive” includes any material determined to be within the scope of USC titles 18: chapter 40 and also includes any material classified as an explosive other than consumer fireworks, 1.4G (Class C, Common) by the hazardous materials regulations of DOTn49 CFR.
High explosive
Explosive material, such as dynamite, which can by caused to detonate by means of a No. 8 test-blasting cap when unconfined.
Low explosive
Explosive material that will burn or deflagrate when ignited. It is characterized by a rate of reaction that is less than the speed of sound. Examples of low explosives include, but are not limited to, black powder; safety fuse; igniters; igniter cord; fuse lighters; fireworks, 1.3G (Class B, Special) and propellants, 1.3 C.
Mass-detonating explosives:
Division 1.1, 1.2 and 1.5 explosives alone or in combination or loaded into various types of ammunition or containers, most of which can be expected to explode virtually instantaneously when a small portion is subjected to fire, sever concussion, impact, the impulse of an initiating agent or the effect of a considerable discharge of energy from without. Materials that react in this manner represent a mass explosion hazard. Such an explosion will normally cause sever structural damage to adjacent objects. Explosive propagation could occur immediately to other items of ammunition and explosives stored sufficiently closed to and not adequately protected from the initially exploding pile with a time interval short enough so that two or more quantities must be considered as one for quantity-distance purposes.
UN/DOTn Class 1 explosives.
The former classification system used by DOTn included the terms “high” and “low” explosives as defined herein. The following terms further define explosives under the current system applied by DOTN for all explosive materials defined as hazard Class 1 materials. Compatibility group letters are used in concert with the division to specify further limitations on each division noted (i.e., the letter G identifies the material as a pyrotechnic substances or article containing a pyrotechnic substance and similar materials).
Division 1.1.
Explosives that have a mass explosion hazard. A mass explosion is one which affects almost the entire load instantaneously.
Division 1.2.
Explosives that have a projection hazard but not a mass explosion hazard.
Division 1.3.
Explosives that have a fire hazard and either a minor blast hazard or a minor projection hazard or both, but not a mass explosion hazard.
Division 1.4.
Explosives that pose a minor explosion hazard. The explosive effects are largely confined to the package and no projection of fragments of appreciable size or range is to be expected. An external fire must not cause virtually instantaneous explosion of almost the entire contents of the package.
Division 1.5.
Very insensitive explosives. The division of comprised of substances that have a mass explosion hazard, but that are so insensitive there is very little probability of initiation or of transition from burning to detonation under normal conditions of transport.
Division 1.6.
Extremely insensitive articles which do not have a mass explosion hazard. This division is comprised of articles that contain only extremely insensitive detonating substances and which h demonstrates a negligible probability of accidental initiation or propagation.
-- Fireworks:
Any composition or device of the purpose of producing a visible or audible effect for entertainment purposes by combustion, deflagration or detonation that meets the detonation of 1.4G fireworks or 1.3G fireworks as set forth herein.
-- Fireworks, 1.3G:
(Formerly Class B, Special Fireworks) Large fireworks devices, which are explosive materials, intended for use in fireworks displays and designed to produce audible or visible effects by combustion, deflagration or detonation. Such 1.3G fireworks include, but are not limited to, firecrackers, containing more than 130 milligrams (2 grains) of explosive composition, aerial shells containing more than 40 grams of pyrotechnic composition, and other display pieces which exceed the limits for classification as 1.4 G fireworks. Such as 1.3G fireworks are also described as fireworks, 49 CFR (172) by the DOTn.
-- Fireworks, 1.4G:
(Formerly Class C, Common Fireworks) Small fireworks devices containing restricted amounts of pyrotechnic composition designed primarily to produce visible or audible effects by combustion. Such 1.4G fireworks which comply with the construction, chemical composition and labeling regulations of the DOTn for fireworks, 49 CFR (172), and the U.S. Consumer Product Safety Commission (CPSC) as set forth in CPSC 16 CFR: Parts 1500 and 1507, are not explosive materials for the purpose of this code.
-- Flammable Gas:
A material that is a gas at 68 degrees F (20 degrees C) or less at 14.7 pounds per square inch atmosphere (psia) (101 kPa) of pressure [a material that has a boil point of 68 degrees F (20 degrees C) in accordance with ASTM E 681.
-- Flammable Liquefied Gas:
A liquefied compressed gas which, under a charged pressure, is partially liquid at a temperature of 68 degrees (20 degrees C) and which is flammable.
Flammable Liquid. A liquid having a closed cup flash point below 100 degrees F (38 degrees C). Flammable liquids are further categorized into a group known as Class I liquids. The class I category is subdivided as follow:
Class IA.
Liquids having a flash point below 73 degrees F (23 degrees C) and a boiling point below 100 degrees F (38 degrees C).
Class IB.
Liquids having a flash point below 73 degrees F (23 degrees C) and a boiling pint at or above 100 degrees F (38 degrees C).
Class IC.
Liquids having a flash point at or above 73 degrees F (23 degrees C) and below 100 degrees F (38 degrees C).
The category of flammable liquids does not include compressed gasses or cryogenic fluids.
-- Flammable material:
A material capable of being readily ignited from common sources of heat or at a temperature of 600 degrees F (316 degrees C) or less.
-- Flammable solid:
A solid, other than a blasting agent or explosive, that is capable of causing fire through friction, absorption or moisture, spontaneous chemical change, or retained heat from manufacturing or processing, or which has an ignition temperature below 212 degrees F (100 degrees C) or which burns so vigorously and persistently when ignited as to create a serous hazard. A chemical shall be considered a flammable solid as determined in accordance with the test method of CPSC 16 CFR; Part 1500.44, if it ignites and burns with a self-sustained flame at a rate greater than .1 inch (2.5 mm) per second along its major axis.
-- Flash Point:
The minimum temperature in degrees Fahrenheit at which a liquid will give off sufficient vapors to form an ignitable mixture with air near the surface or in the container, but will not sustain combustion. The flash point of a liquid shall be determined by appropriate test procedure and apparatus as specified in ASTM D 56, ASTM D 93 OR ASTM D 3278.
-- Handling:
The deliberate transport by any means to a point of storage or use.
-- Hazardous materials:
Those chemicals or substances that are physical hazards or health hazards defined and classified in this section and the International Fire Code, whether the materials are in usable or waste condition.
-- Health Hazard:
A classification of a chemical for which there is statistically significant evidence that acute or chronic health effects are capable of occurring in exposed persons. The terms “health hazard” includes chemicals that are toxic or highly toxic, and corrosive.
-- Highly toxic:
A material which produces a lethal dose or lethal concentration that falls within any of the following categories:
1. A chemical that has a median lethal dose (LD50) of 50 milligrams or less per kilogram of body weight when administered orally to albino rats weighing between 200 and 300 grams each.
2. A chemical that has a median lethal dose (LD50) of 200 milligrams or less per kilogram of body weight when administered by continuous contact for 24 hours (or less if death occurs within 24 hours) with the bare skin of albino rabbits weighing between 2 and 3 kilograms each.
3. A chemical that has a median lethal concentration (LC50) in air of 200 parts per million by volume or less of gas or vapor, or 2 milligrams per liter or less of mist, fume, or dust, when administered by continuous inhalation for 1 hour (or less if death occurs within 1 hour) to albino rats weighing between 200 and 300 grams each.
Mixtures of these materials with ordinary materials, such as water, might not warrant classification as highly toxic. While this system is basically simple in application, any hazard evaluation that is required for the precise categorization of this type of material shall be performed by experienced, technically competent persons.
-- Incompatible materials:
Materials that, when mixed, have the potential to react in a manner that generates heat, fumes, gases or byproducts which are hazardous to life or property.
-- Open system:
The use of solid or liquid hazardous material involving a vessel or system that is continuously open to the atmosphere during normal operations and where vapors are liberated, or the product is exposed to the atmosphere during normal operations. Examples of open systems for solids and liquids include dispensing from or into open beakers or containers, dip tank and plating tank operations.
-- Operating building:
A building occupied in conjunction with the manufacture, transportation or use of explosive materials. Operating buildings are separated from one another with the use of interplant or intraline distances.
-- Organic peroxide:
An organic compound that contains the bivalent -O-O- structure and which may be considered to be a structural derivative of hydrogen peroxide where one or both of the hydrogen atoms have been replaced by an organic radical. Organic peroxides can pose an explosion hazard (detonation or deflagration) or they can be shock sensitive. They can also decompose into various unstable compounds over an extended period of time.
Class I.
Those formulations that are capable of deflagration but not detonation.
Class II.
Those formulations that burn very rapidly and that pose a moderate reactivity hazard.
Class III.
Those formulations that burn rapidly and that pose a moderate reactivity hazard.
Class IV.
Those formulations that burn in the same manner as ordinary combustibles and that pose a minimal reactivity hazard.
Class V.
Those formulations that burn with less intensity than ordinary combustibles or do not sustain combustion and that pose no reactivity hazard.
Unclassified detonable.
Organic peroxides that are capable of detonation. These peroxides pose extremely high explosion hazard through rapid explosive decomposition.
-- Oxidizer:
A material that readily yields oxygen or other oxidizing gas, or that readily reacts to promote or initiate combustion of combustible materials. Examples o other oxidizing gases include bromine, chlorine and fluorine.
Class 4.
An oxidizer that can under go an explosive reaction due to contamination or exposure to thermal or physical shock. Additionally, the oxidizer will enhance the burning rate and can cause spontaneous ignition of combustibles.
Class 3.
An oxidizer that will cause a sever increase in the burning rate of combustible materials with which it comes in contact or that will undergo vigorous self-sustained decomposition due to contamination or exposure to heat.
Class 2.
An oxidizer that will cause a moderate increase in the burning rate or that causes spontaneous ignition of combustible materials with which it comes in contact.
Class 1.
An oxidizer whose primary hazard is that is slightly increases the burning rate but which does not cause spontaneous ignition when it comes in contact with combustible materials.
-- Oxidizing gas:
A gas that can support and accelerate combustion of other materials.
-- Physical hazard:
A chemical for which there is evidence that is a combustible liquid, compressed gas, cryogenic, explosive, flammable gas, flammable liquid, flammable solid, organic peroxide, oxidizer, pyrophoric or unstable (reactive) or water-reactive material.
-- Pyrophoric:
A chemical with an auto ignition temperature in air, at or below a temperature of 130 degrees F (54.4 degrees C).
-- Pyrotechnic composition:
A chemical mixture that produces visible light displays or sounds through a self-propagation, heat-releasing chemical reaction which is initiated by ignition.
-- Toxic:
A chemical falling within any of the following categories:
1. A chemical that has a median lethal dose (LD50) of more than 50 milligrams per kilogram, but not more than 500 milligrams per kilogram of body weight when administered orally to albino rats weighing between 200 and 300 grams each.
2. A chemical that has a median lethal dose (LD50) of more than 200 milligrams per kilogram but not more than 1,000 milligrams per kilogram of body weight when administered by continuous contact for 24 hours (or less if death occurs within 24 hours) with the bare skin of albino rabbits weighing between 2 and 3 kilograms each.
3. A chemical that has a median lethal concentration (LC50) in air of more than 200 parts per million but not more than 2,000 parts per million by volume of gas or vapor, or more than 2 milligrams per liter but not more than 20 milligrams per liter of mist, fume or dust, when administered by continuous inhalation for 1 hour (or less if death occurs within 1 hour) to albino rats weighing between 200 and 300 grams each.
-- Unstable (reactive) material:
A material, other than an explosive, which in the pure state or as commercially produces, will vigorously polymerize, decompose, condense or become self reactive and undergo other violent chemical changes, including explosion, when exposed to heat, friction or shock, or in the absence of an inhibitor, or in the presence of contaminants, or in contact incompatible materials. Unstable (reactive) materials are subdivided as follows:
Class 4.
Materials that in themselves are readily capable of detonation or explosive decomposition or explosive reaction at normal temperatures and pressures. This class includes materials that are sensitive to mechanical or localized thermal shock at normal temperatures and pressures.
Class 3.
Materials that in themselves are capable of detonation or of explosive decomposition or explosive reaction but which require a strong initiating source or which must be heated under confinement before initiation. This class includes materials that are sensitive to thermal or mechanical shock at elevated temperatures and pressures.
Class 2.
Materials that in themselves are normally unstable and readily undergo violent chemical change but do not detonate. This class includes materials that can undergo chemical change with rapid release of energy at normal temperatures and pressures, and that can undergo violent chemical change at elevated temperatures and pressures.
Class 1.
Materials that in themselves are normally stable but which can become unstable at elevated temperatures and pressure.
-- Water-reactive material:
A material that explodes; violently reacts; produces flammable. Toxic or other hazardous gases; or evolves enough heat to cause self-ignition or ignition of nearby combustibles upon exposure to water or moisture. Water-reactive materials are subdivided as follow:
Class 3.
Materials that react explosively with water without requiring heat or confinement.
Class 2.
Materials that may form potentially explosive mixtures with water.
Class 1.
Materials that may react with water with some release of energy, but not violently.
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:
Explosives
Division 1.1
Division 1.2
Division 1.3
Exception: 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 H-2 occupancies.
Division 1.4
Exception: Articles, including articles packaged for shipment, that are not regulated as an explosive under Bureau of Alcohol, Tobacco and Firearms regulations, or unpackaged articles used in process operations that do no propagate a detonation or deflagration between articles shall be allowed in H-3 occupancies.
Division 1.5
Division 1.6
Organic peroxides, unclassified detonable
Oxidizers, Class 4
Unstable (reactive) materials, Class 3 detonable and Class 4
Detonable pyrophoric materials
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, IIIA flammable or combustible liquids which are used or stored in normally open containers or systems, or in closed containers or systems pressurized at more than 15 psi (103.4 kPa) gage.
- Combustible dusts
- Cryogenic fluids, flammable
- Flammable gases
- 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 psi (103 kPa) gage
- Pyrophoric liquids, solids and gases, nondetonable
- Unstable (reactive) materials, Class 3, nondetonable
- Water-reactive materials, Class 3
307.5 High-Hazard Group H-4.
Building and structures which contain materials that are health hazards shall be classified as Group H-4. Such materials shall include, but not be limited to, the following:
- Corrosives
- Highly toxic materials
- Toxic materials
307.7 Group H-5 Structures.
Semiconductor fabrication facilities and comparable research and development areas in which hazardous production materials (HPM) are use and the aggregate quantity of materials is in excess of those listed in Tables 307.7 (1) and 307.7 (2). Such facilities and areas shall be designed and constructed in accordance with Section 415.9.
307.8 Multiple Hazards.
Buildings and structures containing a material or materials representing hazards that are classified in one or more of Groups H-1, H-2, H-3 and H-4 shall conform to the code requirements for each of the occupancies so classified.
307.9 Exceptions: The following shall not be classified in Group H, but shall be classified in the occupancy that they most nearly resemble. Hazardous materials in any quantity shall conform to the requirements of this code, including Section 414, and the International Fire Code.
1. Buildings and structures that contain not more than the maximum allowable quantities per control area of hazardous materials as shown in Tables 307.7 (1) and 307.7 (2) provided that such building are maintained in accordance with the International Fire Code.
2. Buildings utilizing control areas in accordance with Section 414.2 that contain not more than the maximum allowable quantities per control area of hazardous materials as shown in Tables 307.7(1) and 307.7(2).
3. 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.
4. Wholesale and retail sales and storage of flammable and combustible liquids or gases in mercantile occupancies conforming to the International Fire Code.
5. Closed systems housing flammable or combustible liquids or gases utilized or the operation of machinery or equipment.
6. Cleaning establishments that utilize combustible liquids or gases utilized for the operation of machinery or equipment.
7. Cleaning establishments which utilize a liquid solvent having a flash point at or above 200 degrees F (93 degrees C).
8. Liquor stores and distributors without bulk storage.
9. Refrigeration systems.
10. The storage or utilization of materials for agricultural purposes on the premises.
11. 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. Corrosives shall not include personal or household products in their original packaging used in retail display or commonly used building materials.
12. Corrosives shall not include personal or household products in their original packaging used in retail display or commonly used building materials.
13. 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.
14. 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 414.2.4.
15. 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 requirements prescribed in the International Fire Code.