GAS A state of matter in which the molecules, which are moving rapidly, are separate from one another except when undergoing collisions. See liquid and solid, the other states of matter. [Friedman 1989]

GAS A state of matter in which the material has very low density and viscosity; can expand and contract greatly in response to changes in temperature and pressure; easily diffuses into other gases; readily and uniformly distributes itself throughout any container. A gas can be changed to a liquid or solid state by the combined effect of increased pressure and/or decreased temperature. HAZARDOUS MATERIALS EMERGENCY RESPONSE GLOSSARY OF STANDARDIZED TERMS, State of California's Chemical Emergency Planning and Response Commission, 1991

GAS LAWS Physical laws describing the behavior of a gas (see States Of Matter) under various conditions of volume ( V ), pressure ( P ), and absolute, or Kelvin, Temperature ( T ). Boyle's, or Mariotte's, gas law states that under constant temperature PV = k1. Charles', or Gay-Lussac's, law states that under constant pressure V = k2T. A third law states that under constant volume P = k3T. The constants k1 , k2 , and k3 are dependent on the amount of gas present and, respectively, on the temperature, pressure, and volume of the gas. These three laws can be combined into a single law, or equation of state: PV = kT or Pv = RT. These laws are formulated for so-called ideal or perfect gases. Real gases are described more accurately by the van der Waals equation: (P + a/v2) (v - b) = RT , in which ( a ) and ( b ) are specific constants for each gas. (Hydro Cut General Terminology Resource Information)

GASES (properties of) Gases consist of individual atoms or molecules moving at high velocities (approximately at the speed of sound, which is about 300 meters per second). At atmospheric pressure and room temperature, the atoms or molecules themselves occupy only about 0.1% of the space and the remaining 999% of the space is empty. Each atom or molecule is colliding with others and changing direction about 109 times per second. If the temperature of a gas is increased, at constant pressure, the average velocity of the atoms or molecules increases and the gas expands. [Friedman 1989]

GASOLINE Gasoline is a light, volatile fuel oil; called petrol in Britain. A mixture of Hydrocarbons obtained in the fractional Distillation and ôcrackingö of Petroleum, it is used as a fuel for internal-combustion engines, for cooking, and as a solvent. The quality of gasoline used in engines is rated by Octane Number. To increase octane rating, lead additives were once widely used. Because of the possible health hazard of lead as an environmental pollutant and the harmful effect it has on pollution-control devices, however, a program was begun in the U.S. in the 1970s to change automobile design and gasoline composition, so that lead additives could be gradually eliminated. (Hydro Cut General Terminology Resource Information)

GAUGE (Wire) A series of standard sizes such as the American Wire Gauge (AWG), used to specify the diameter of wire. (Hydro Cut General Terminology Resource Information)

GELLING A process of adding a specific material that is designed to coagulate a liquid facilitating its isolation and removal. HAZARDOUS MATERIALS EMERGENCY RESPONSE GLOSSARY OF STANDARDIZED TERMS, State of California's Chemical Emergency Planning and Response Commission, 1991

GLOWING COMBUSTION Luminous burning of solid material without a visible flame. [NFPA 921 - 1992]

GLOWING COMBUSTION A term applied to smoldering combustion when a glow is visible (radiation from a hot surface). [Friedman 1989]

GLOSSARY OF TERMS (INTRODUCTION TO) The express purpose of the Hazardous Materials Emergency Response Glossary of Standardized Terms is to provide common and readily understandable definitions to facilitate communications and operations among hazardous materials emergency responders when dealing with hazardous materials incidents. This document is not intended as a legal or scientific reference. HAZARDOUS MATERIALS EMERGENCY RESPONSE GLOSSARY OF STANDARDIZED TERMS, State of California's Chemical Emergency Planning and Response Commission, 1991

GRADE ...means the average level of finished ground adjoining a building at all exterior walls. (Ontario Fire Code 1996)

GROUNDING Method whereby activities which may generate static electricity will be prevented from discharging a spark and thereby not produce an ignition point. HAZARDOUS MATERIALS EMERGENCY RESPONSE GLOSSARY OF STANDARDIZED TERMS, State of California's Chemical Emergency Planning and Response Commission, 1991

GROUP That organization level within the incident command system having responsibility for operations within a specific functional area, i.e. salvage, ventilation, haz-mat. (NIIMS) HAZARDOUS MATERIALS EMERGENCY RESPONSE GLOSSARY OF STANDARDIZED TERMS, State of California's Chemical Emergency Planning and Response Commission, 1991

GROWTH OF A FIRE However, it must be said that chemistry is not the whole story. Two other key factors must be considered : heat transfer and fluid mechanics. The radiative, convective, and conductive transfer of heat from the flame and the hot fire products to the burning and the not-yet burning combustibles are vital in governing the growth of a fire. The buoyant rise of hot gases, drawing fresh air into the fire, the mixing of the fire gases with ambient air, and the motion of the fire products through a building, usually with layering, are important aspects of fires. Heat transfer and fluid mechanics are interrelated because the motion of a hot gas affects the rate of heat transfer from a gas to the surroundings, and the temperature of a gas affects its buoyancy, which induces its motion. [Friedman 1989]  

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HALOGEN Any of the elements fluorine, chlorine, bromine, iodine, or astatine. [Friedman 1989]

HALOGEN Any of the five chemical elements in group VIIa of the Periodic Table. Fluorine, Chlorine, Bromine, Iodine, and the radioactive Astatine are nonmetallic, monovalent negative ions and exist in pure form as diatomic molecules. The first four elements exhibit an almost perfect gradation of physical properties. Fluorine is the least dense and chemically the most active, displacing other halogens from their compounds and oxygen from water. Iodine is the least active. The halogens form numerous compounds with each other, and with other elements, such as hydrogen halides, metal halides (Salts), and halocarbons. (Hydro Cut General Terminology Resource Information)

HALOGENS A chemical family that includes fluorine, chlorine, bromine, and iodine. HAZARDOUS MATERIALS EMERGENCY RESPONSE GLOSSARY OF STANDARDIZED TERMS, State of California's Chemical Emergency Planning and Response Commission, 1991

HALONS Various synthetic chemicals, the molecules of which consist of combinations of carbon, fluorine, chlorine, and bromine. [Friedman 1989]
HAZARD Any situation that has the potential for causing damage to life, property, and/or the environment. HAZARDOUS MATERIALS EMERGENCY RESPONSE GLOSSARY OF STANDARDIZED TERMS, State of California's Chemical Emergency Planning and Response Commission, 1991

HAZARD ASSESSMENT A process used to qualitatively or quantitatively assess risk factors to determine incident operations. HAZARDOUS MATERIALS EMERGENCY RESPONSE GLOSSARY OF STANDARDIZED TERMS, State of California's Chemical Emergency Planning and Response Commission, 1991

HAZARD CLASS The eight classes of hazardous materials as categorized and defined by the Department of Transportation in 49 CFR. HAZARDOUS MATERIALS EMERGENCY RESPONSE GLOSSARY OF STANDARDIZED TERMS, State of California's Chemical Emergency Planning and Response Commission, 1991

HAZARDOUS CHEMICAL A term used by the United States Occupational Safety and Health Administration (OSHA) to denote any chemical that would be a risk to employees if exposed in the workplace. The list of hazardous chemicals is found in 29 CFR. HAZARDOUS MATERIALS EMERGENCY RESPONSE GLOSSARY OF STANDARDIZED TERMS, State of California's Chemical Emergency Planning and Response Commission, 1991

HAZARDOUS LOCATION ...means a location that is or may become subject to conditions conducive to the rapid development of fire or explosion. (Ontario Fire Code 1996)

HAZMAT dangerous goods (STANDARDIZED), dangerous material, hazardous material, dangerous commodities (STANDARDIZED), dangerous articles (STANDARDIZED), hazardous commodities (STANDARDIZED), hazardous goods, hazardous products, hazardous materiel, HAZMAT (CORRECT)
Those substances classified as dangerous by the United Nations Committee of experts on the transport of dangerous goods or by the competent authority .... Explosive, toxic, caustic, nuclear, combustible, or flammable, biological, infectious, or poisonous materials that may, directly or indirectly, endanger human life or property, particularly if mishandled, misused or involved in accidents. ... the nine classifications of hazardous material [are:] ... Explosives ... Flammable and Non-Flammable ... Compressed Gas ... Flammable Liquids and Solids ... Oxidizers/Organic Peroxides ... Poison and Infectious Substances ... Radioactive ... Corrosives ... Miscellaneous. The terms "hazardous commodities" and "dangerous articles" are standardized by the Canadian General Standards Board; the term "dangerous goods" is standardized by ISO and is used in the Canadian "Transportation of Dangerous Goods Act", chapter 36. The spelling "materiel" with an "e" is reserved for military equipment. dangerous goods: Term and definition standardized by ICAO. (Source : Termium 1996)

HAZARDOUS MATERIAL A substance (solid, liquid, or gas) capable of posing an unreasonable risk to health, safety, environment or property. HAZARDOUS MATERIALS EMERGENCY RESPONSE GLOSSARY OF STANDARDIZED TERMS, State of California's Chemical Emergency Planning and Response Commission, 1991

HAZARDOUS MATERIALS RESPONSE TEAM (HMRT) An organized group of employees, designated by the employer, who are expected to perform work to handle and control actual or potential leaks or spills of hazardous substances requiring possible close approach to the substance. A Haz-Mat Team may be a separate component of a fire brigade or a fire department or other appropriately trained and equipped units from public or private agencies. HAZARDOUS MATERIALS EMERGENCY RESPONSE GLOSSARY OF STANDARDIZED TERMS, State of California's Chemical Emergency Planning and Response Commission, 1991

HAZARDOUS MATERIALS RESPONSE TEAM - TECHNICIAN LEVEL Shall consist of an organized group of employees, designated by the employer in compliance with 8 CCR 5192(q)(6), trained to function at the hazardous materials incident at the Technician Level in accordance with NFPA 472, Chapter 3 (1990). Additionally, personnel on the team shall be capable of the following:
1). The ability to carry out the duties of these positions as identified in FIRESCOPE ICS-HM-120.

a. Group Supervisor
b. Entry Leader
c. Hazardous Material Safety Officer
d. Site Access Control Officer
e. Decontamination Leader
f. Technical Specialist-Hazardous Material

(Multiple positions can be handled by one person dependent upon the complexity and/or severity of the incident.)

2). Members shall be assigned positions in accordance with 8 CCR 5192 appropriately trained to include but not be limited to entry with splash protective clothing.

a. Entry Team: 2
b. Backup Team 2

Reference: HAZARDOUS MATERIALS EMERGENCY RESPONSE GLOSSARY OF STANDARDIZED TERMS, State of California's Chemical Emergency Planning and Response Commission, 1991

HAZARDOUS MATERIALS RESPONSE TEAM - SPECIALIST LEVEL Shall consist of an organized group of employees, designated by the employer in compliance with 8 CCR 5192(q)(6), trained to function at the hazardous materials incident at the Specialist Level in accordance with NFPA Standard 472, Chapter 4 (1990). Additionally, personnel on the team shall be capable of the following:
1). The ability to carry out the duties of these positions as identified in FIRESCOPE ICS-HM-120

a. Group Leader
b. Entry Team Leader
c. Hazardous Material Safety Officer
d. Site Access Control Officer
e. Decontamination Leader
f. Technical Specialist-Hazardous Material

Reference
(Multiple positions can be handled by one person dependent upon the complexity and/or severity of the incident.)

2). Members shall be assigned positions in accordance with 8 CCR 5192 appropriately trained for entry with vapor protective clothing.

a. Entry Team: 2
b. Backup Team: 2

HAZARDOUS MATERIALS EMERGENCY RESPONSE GLOSSARY OF STANDARDIZED TERMS, State of California's Chemical Emergency Planning and Response Commission, 1991

HAZARDOUS MATERIALS RESPONSE TEAM - SPECIALTY Shall consist of an organized group of employees, designated by the employer in compliance with 8 CCR 5192(q)(6), who are trained in the hazards of specific hazardous substances, and/or specific techniques or support services, and/or the provision of specialized technical advice and assistance in compliance with 8 CCR 5192(q)(5). The Team shall be capable, either within their own team or in agreement with a Hazardous Materials Response Team on scene, of the following:
1). The ability to carry out the duties of these positions as identified in Firescope ICS-HM-120.

a. Group Supervisor
b. Entry Team Leader
c. Hazardous Material Safety Officer
d. Site Access Control Officer
e. Decontamination Leader
f. Technical Specialist-Hazardous Material

Reference
(Multiple positions can be handled by one person dependent upon the complexity and/or severity of the incident.)
2). Members shall be assigned positions in accordance with 8 CCR 5192 appropriately trained to include but not be limited to entry with splash protection.

a. Entry team: 2
b. Backup team: 2

HAZARDOUS MATERIALS EMERGENCY RESPONSE GLOSSARY OF STANDARDIZED TERMS, State of California's Chemical Emergency Planning and Response Commission, 1991

HAZARDOUS SUBSTANCE Hazardous Substance, as used by the California Department of Toxic Substances Control, encompasses every chemical regulated by both the Department of Transportation (hazardous materials) and the Environmental Protection Agency (hazardous waste), including emergency response. (8 CCR 5192) HAZARDOUS MATERIALS EMERGENCY RESPONSE GLOSSARY OF STANDARDIZED TERMS, State of California's Chemical Emergency Planning and Response Commission, 1991

HAZARDOUS WASTE 1) Waste materials or mixtures of waste which require special handling and disposal because of their potential to damage health and/or the environment.
2) The Environmental Protection Agency uses the term hazardous waste for chemicals that are regulated under the Resource Conservation and Recovery Act and are listed in 40 CFR 261.33 (d). Environmental Protection Agency or California Department of Toxic Substances Control regulated hazardous waste, when in transport, must also meet 49 CFR parts 170 through 179. California's list of hazardous waste is more inclusive than EPA's. HAZARDOUS MATERIALS EMERGENCY RESPONSE GLOSSARY OF STANDARDIZED TERMS, State of California's Chemical Emergency Planning and Response Commission, 1991

HAZARDOUS WASTE GENERATION The act or process of producing hazardous waste. HAZARDOUS MATERIALS EMERGENCY RESPONSE GLOSSARY OF STANDARDIZED TERMS, State of California's Chemical Emergency Planning and Response Commission, 1991

HAZARDOUS WASTE LANDFILL An excavated or engineered area on which hazardous waste is deposited and covered. Proper protection of the environment from the materials to be deposited in such a landfill requires careful site selection, good design, proper operation, leachate collection and treatment, and thorough final closure. HAZARDOUS MATERIALS EMERGENCY RESPONSE GLOSSARY OF STANDARDIZED TERMS, State of California's Chemical Emergency Planning and Response Commission, 1991

HAZARDOUS WASTE LEACHATE Any liquid that has percolated through or drained from hazardous waste emplaced in or on the ground. HAZARDOUS MATERIALS EMERGENCY RESPONSE GLOSSARY OF STANDARDIZED TERMS, State of California's Chemical Emergency Planning and Response Commission, 1991

HAZARDOUS WASTE MANIFEST, UNIFORM (EPA USAGE) The shipping document, originated and signed by the waste generator or an authorized representative, that contains the information required by law and must accompany shipments of hazardous waste. (40 CFR 262, Subpart B) HAZARDOUS MATERIALS EMERGENCY RESPONSE GLOSSARY OF STANDARDIZED TERMS, State of California's Chemical Emergency Planning and Response Commission, 1991

HAZARDOUS WASTE SITE A location where hazardous wastes are located. HAZARDOUS MATERIALS EMERGENCY RESPONSE GLOSSARY OF STANDARDIZED TERMS, State of California's Chemical Emergency Planning and Response Commission, 1991

HEAT The internal Energy of a substance, associated with the positions and motions of its component molecules, atoms, and ions. The average kinetic energy of the molecules or atoms, which is due to their motions, is measured by the Temperature of the substance; the potential energy is associated with the state, or phase, of the substance ( States Of Matter). Heat energy is commonly expressed in Calories, British Thermal Units (BTU), or Joules, ( Work). Heat may be transferred from one substance to another by three means: Conduction, Convection, and Radiation. Also Heat Capacity; Specific Heat; Thermodynamics. Originally an abbreviation for "high explosive antitank." A term used to designate high explosive ammunition containing a shaped charge. High-Explosive Antitank Shell. (Hydro Cut General Terminology Resource Information)

HEAT CAPACITYHeat capacity or thermal capacity, ratio of the change in Heat energy of a unit mass of a substance to the change in Temperature of the substance. The heat capacity is a characteristic of a substance; it is often expressed in Calories per gram per degree Celsius or British Thermal Units per pound per degree Fahrenheit. Also Specific Heat. (Hydro Cut General Terminology Resource Information)

HEAT DETECTOR ...means a fire detector designed to operate at a predetermined temperature or rate of temperature rise. (Ontario Fire Code 1996)

HEATING OIL (No.2) Fires involving liquids in the form of sprays or thin films are different because the fire point temperature is no longer a relevant measure of flammability. A pool of domestic fuel oil (No.2) at 20C (68F) cannot be ignited with a match (unless a wick is present), but the same oil, in the form of a spray, mist, or thin film, can be ignited easily. [Friedman 1989]

HEAT OF COMBUSTION It has been determined (Hugget, 1980) that if the heat of combustion of a substance is expressed as kilojoules per gram of the air required by the principles of combining proportions, then the heat of combustion is nearly the same for most combustible substances. The value is 3 kilojoules per gram of air required. [Friedman 1989]

HEAT OF COMBUSTIONHeat evolved in the complete oxidation of a substance under standard conditions of pressure and temperature. (Hydro Cut General Terminology Resource Information)

HEAT OF EXPLOSIONHeat evolved in burning (exploding) a sample in a combustion bomb in an inert atmosphere under standard conditions of pressure and temperature. Products of explosion vary with the oxygen balance of the sample. (Hydro Cut General Terminology Resource Information)
HEAT OF FORMATION Heat evolved, or absorbed, when a compound is formed by combination of its elements. (Hydro Cut General Terminology Resource Information)

HEAT OF FUSION (see Heat of Vaporization) When a solid melts, an energy change is involved and heat must be added to the solid to convert it to a liquid. For example, 334 joules of heat energy must be added to 1 gram of ice at 0C to convert it to liquid water at 0C. This energy is called the heat of fusion. [Friedman 1989]

HEAT OF REACTION Heat evolved when a sample is burned in a combustion bomb in an atmosphere of helium or other inert gas. (Hydro Cut General Terminology Resource Information)

HEAT OF VAPORIZATION (see Heat of Fusion) To convert liquid water at 100C to water vapor at 100C, a heat of vaporization must be supplied. For water, this is 2257 joules per gram at 100C. The heat of vaporization of hexane ("mineral spirits") is only 342 joules per gram, and this explains why hexane evaporates much more readily than water. [Friedman 1989]

HEAVY METAL A high density metallic element that may demonstrate health hazards as a result of exposure and may contribute to contamination of the environment. This includes chromium (Cr), beryllium (Be), lead (Pb), mercury (Hg), zinc (Zn), copper (Cu), cadmium (Cd) and others. HAZARDOUS MATERIALS EMERGENCY RESPONSE GLOSSARY OF STANDARDIZED TERMS, State of California's Chemical Emergency Planning and Response Commission, 1991

HEAVY TIMBER CONSTRUCTION ...means that type of combustible construction in which a degree of fire safety is attained by placing limitations on the sizes of wood structural members and on thickness and composition of wood floors and roofs, by avoidance of concealed spaces under floors and roofs and by use of approved fastenings, construction details and adhesives for structural members. (Ontario Fire Code 1996)

HEMOGLOBIN A molecule in the blood that carries oxygen from the lungs to cells throughout the body. A typical formula is [C738H1166O208N203S2Fe]4. [Friedman 1989]

HENDIADYS / use of two words connected by a conjunction, instead of subordinating one to the other, to express a single complex idea.
*It sure is nice and cool today! (for "pleasantly cool")
*I love the Lord, because he hath heard my voice and my supplications. Psalms 116 (A Glossary of Rhetorical Terms with Examples, Ross Scaife)

HIGH HAZARD INDUSTRIAL OCCUPANCY (Group 'F' Division 1) ...means an industrial occupancy that contains sufficient quantities of highly combustible and flammable or explosive materials that, because of their inherent characteristics, constitute a special fire hazard. (Ontario Fire Code 1996)

HOMOLOGOUS SERIES A series of similar organic compounds, differing only in that the next higher member of the series has an additional CH2 group (one carbon atom and two hydrogen atoms) in its molecular structure. Fuel oils are characterized by the presence of an identifiable homologous series of normal alkanes.
Diesel Fuel :
Diesel Fuel consists mostly of hydrocarbons ranging from C10 to C24. The composition of diesel fuel may vary with changes in latitude or changes in season. This variability is provided by the refinery to control the volatility of the product. In order to be identified as diesel fuel, a sample extract must exhibit a homologous series of five or more consecutive normal alkanes ranging from C12 through C22. Diesel fuel has a flash point of 120 to 160 F and explosive limits of 0.7% to 5%. Many states specify a minimum flash point for diesel fuel.
Fuel Oil :
A heavy petroleum distillate ranging from #1 (kerosene or range oil), #2 (diesel fuel), up through #6 (heavy bunker fuels). To be identified as fuel oil, a sample must exhibit a homologous series of normal alkanes ranging from C9 upward.
Gasoline :
A mixture more than 200 volatile hydrocarbons in the range of C4 to C12 , suitable for use in spark ignited internal combustion engine. Regular automotive gasoline has a flash point of -40 F.
Kerosene (#1 Fuel Oil):
Flash point generally between 100 and 150 degrees F. Explosive limits of 0.7% to 5.0%. Kerosene consists mostly of C9 through C17 hydrocarbons. In order to be identified as kerosene, a sample extract must exhibit a homologous series five consecutive normal alkanes between C9 and C17. Kerosene is the most common 'incidental' accelerant, as it is used in numerous household products ranging from charcoal lighter fluid to lamp oil to paint thinner to insecticide carriers. It is also used as jet fuel. K-1 kerosene has a low sulfur content required for use in portable space heaters.
Source : GLOSSARY OF TERMS RELATED TO CHEMICAL AND INSTRUMENTAL ANALYSIS OF FIRE DEBRIS, Prepared by the IAAI Forensic Science Committee http://www.aurorafire.gov/iaai.htm

HOSE (extension) Where hose must be extended by hand up! stairways, over ladders or for some distance across properties, four men other than the pump operator are recommended. [Kimball 1969]

HOT TAPPING A sophisticated method of welding on and the cutting of holes through liquid, compressed gas vessels, and piping for the purpose of relieving pressure and/or removing product. HAZARDOUS MATERIALS EMERGENCY RESPONSE GLOSSARY OF STANDARDIZED TERMS, State of California's Chemical Emergency Planning and Response Commission, 1991

HOT ZONE An area immediately surrounding a hazardous materials incident, which extends far enough to prevent adverse effects from hazardous materials releases to personnel outside the zone. This zone is also referred to as the "exclusion zone", the "red zone", and the "restricted zone" in other documents. (NFPA 472, 1-3) HAZARDOUS MATERIALS EMERGENCY RESPONSE GLOSSARY OF STANDARDIZED TERMS, State of California's Chemical Emergency Planning and Response Commission, 1991

HYDRANT Another too frequent cause of poor performance is the failure to connect pumpers to hydrants with hose capable of carrying the desired volume of water. Pumpers can utilize all the water available at a single hydrant provided that the proper supply connections have been made. Available flows from hydrants are calculated on the basis of 20 psi residual pressure. In most cases, a short length of supply hose of not less than 4-inch diameter should be connected to the large pumper outlet on the hydrant. For efficient pump operation and to avoid the possibility of damage due to cavitation, a residual pressure of at least 10 psi on the suction side of the pump is desirable. [Kimball 1969]

HYDROCARBON A hydrocarbon is any organic compound composed solely of Carbon and Hydrogen. Hydrocarbons include aliphatic compounds, in which the carbon atoms form a chain, and Aromatic Compounds, in which the carbon atoms form stable rings. The aliphatic group is divided into alkanes (e.g., Methane and Propane), alkenes, and alkynes (e.g., Acetylene), depending on whether the molecules of the compounds contain, respectively, only single bonds, one or more carbon-carbon double bonds, or one or more carbon-carbon triple bonds. Petroleum distillation yields useful fractions that are hydrocarbon mixtures, e.g. Natural Gas, Gasoline, Kerosene, home heating oil, lubricating oils, Paraffin, and asphalt. Coal Tar is also a source of hydrocarbons. Hydrocarbon derivatives contain additional elements, e.g., oxygen, and include Alcohols, aldehydes, ketones, carboxylic acids, and halocarbons. (Hydro Cut General Terminology Resource Information)

HYDROCARBON A hydrocarbon is any organic compound composed solely of Carbon and Hydrogen. Hydrocarbons include aliphatic compounds, in which the carbon atoms form a chain, and Aromatic Compounds, in which the carbon atoms form stable rings. The aliphatic group is divided into alkanes (e.g., Methane and Propane), alkenes, and alkynes (e.g., Acetylene), depending on whether the molecules of the compounds contain, respectively, only single bonds, one or more carbon-carbon double bonds, or one or more carbon-carbon triple bonds. Petroleum distillation yields useful fractions that are hydrocarbon mixtures, e.g. Natural Gas, Gasoline, Kerosene, home heating oil, lubricating oils, Paraffin, and asphalt. Coal Tar is also a source of hydrocarbons. Hydrocarbon derivatives contain additional elements, e.g., oxygen, and include Alcohols, aldehydes, ketones, carboxylic acids, and halocarbons. (Hydro Cut General Terminology Resource Information)

HYDROGEN Hydrogen (H) is a gaseous element, discovered by Henry Cavendish in 1766. The first element on the Periodic Table, hydrogen is colorless, odorless, tasteless, slightly soluble in water, and highly explosive. The hot flame produced by a mixture of oxygen and hydrogen is used in welding, and in melting quartz and glass. Normal hydrogen is diatomic (Allotropy). The most abundant element in the universe, hydrogen is the major fuel in fusion reactions of the Sun and other Stars. Atmospheric hydrogen has three isotopes: protium (nucleus: one proton), the most common; deuterium, or heavy hydrogen (nucleus: one proton and one neutron), used in particle accelerators and as a tracer for studying chemical-reaction mechanisms; and tritium (nucleus: one proton and two neutrons), a radioactive gas used in the hydrogen bomb, in luminous paints, and as a tracer. Hydrogen's principal use is in the synthesis of Ammonia; liquid hydrogen has been greatly used as a rocket fuel, in conjunction with oxygen or fluorine. Deuterium oxide, or heavy water, is used as a moderator in nuclear reactors. Element. (Hydro Cut General Terminology Resource Information)

HYGROSCOPIC A substance that has the property of absorbing moisture from the air, such as silica gel. HAZARDOUS MATERIALS EMERGENCY RESPONSE GLOSSARY OF STANDARDIZED TERMS, State of California's Chemical Emergency Planning and Response Commission, 1991

HYPALLAGE / ("exchanging") transferred epithet; grammatical agreement of a word with another word which it does not logically qualify. More common in poetry. (A Glossary of Rhetorical Terms with Examples, Ross Scaife)

HYPERBATON / separation of words which belong together, often to emphasize the first of the separated words or to create a certain image. (A Glossary of Rhetorical Terms with Examples, Ross Scaife)

HYPERBOLE / exaggeration for emphasis or for rhetorical effect.
*My vegetable love should grow Vaster than empires, and more slow; An hundred years should got to praise Thine eyes and on thine forehead gaze; Two hundred to adore each breast, But thirty thousand to the rest. Andrew Marvell, "To His Coy Mistress" (A Glossary of Rhetorical Terms with Examples, Ross Scaife)

HYPERGOLIC Two chemical substances that spontaneously ignite upon mixing. HAZARDOUS MATERIALS EMERGENCY RESPONSE GLOSSARY OF STANDARDIZED TERMS, State of California's Chemical Emergency Planning and Response Commission, 1991

HYSTERON PROTERON / ("later-earlier") inversion of the natural sequence of events, often meant to stress the event which, though later in time, is considered the more important.
*Put on your shoes and socks! (A Glossary of Rhetorical Terms with Examples, Ross Scaife)

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IGNITABLE MATERIAL Any material having, as a liquid, a flash point less than 140o F or, if not a liquid, is capable of causing fire through friction, absorption of moisture or spontaneous chemical changes. HAZARDOUS MATERIALS EMERGENCY RESPONSE GLOSSARY OF STANDARDIZED TERMS, State of California's Chemical Emergency Planning and Response Commission, 1991

IGNITIONThe onset of combustion. [Friedman 1989]

IGNITION TEMPERATUREMinimum surface temperature a substance must attain in order to ignite under specific TEST CONDITIONS. ... The ignition temperature determined in a standard test is normally lower than the ignition temperature in an actual fire scenario. [NFPA 921 - 1992]

IGNITION TEMPERATUREThe minimum temperature at which a material will ignite without a spark or flame being present. This is also the temperature the ignition source must be. HAZARDOUS MATERIALS EMERGENCY RESPONSE GLOSSARY OF STANDARDIZED TERMS, State of California's Chemical Emergency Planning and Response Commission, 1991

IMMEDIATELY DANGEROUS TO LIFE OR HEALTH (IDLH)An atmospheric concentration of any toxic, corrosive or asphyxiant substance that poses an immediate threat to life or would cause irreversible or delayed adverse health effects or would interfere with an individual's ability to escape from a dangerous atmosphere. (8 CCR 5192(a)3) HAZARDOUS MATERIALS EMERGENCY RESPONSE GLOSSARY OF STANDARDIZED TERMS, State of California's Chemical Emergency Planning and Response Commission, 1991

IMPEDED EGRESS ZONE ...means a supervised area in which occupants have free movement but require the release, by security personnel, of security doors at the boundary before they are able to leave the area, but does not include a contained use area. (Ontario Fire Code 1996)

IMPLOSIONThe opposite of explosion; an inward burst of particles, fragments, etc., due to reduced pressure. (Hydro Cut General Terminology Resource Information)

INCENDIARY1) Chemical agent used primarily for igniting combustible substances with which it is in contact by generating sufficient heat to cause ignition.2) Filling for incendiary munitions such as shells, bombs, grenades and flame throwers. (Hydro Cut General Terminology Resource Information)

INCIDENTAn event involving a hazardous material or a release or potential release of a hazardous material. HAZARDOUS MATERIALS EMERGENCY RESPONSE GLOSSARY OF STANDARDIZED TERMS, State of California's Chemical Emergency Planning and Response Commission, 1991

INCIDENT ACTION PLANA plan which is initially prepared at the first meeting of emergency personnel who have responded to an incident. The Incident Action Plan contains general control objectives reflecting overall incident strategy and specific action plans. HAZARDOUS MATERIALS EMERGENCY RESPONSE GLOSSARY OF STANDARDIZED TERMS, State of California's Chemical Emergency Planning and Response Commission, 1991

INCIDENT COMMANDA disciplined method of management established for the specific purpose of control and direction of resources and personnel. HAZARDOUS MATERIALS EMERGENCY RESPONSE GLOSSARY OF STANDARDIZED TERMS, State of California's Chemical Emergency Planning and Response Commission, 1991

INCIDENT COMMANDER (I.C.)/SCENE MANAGER (S.M.)The person responsible for all decisions relating to the management of the incident. HAZARDOUS MATERIALS EMERGENCY RESPONSE GLOSSARY OF STANDARDIZED TERMS, State of California's Chemical Emergency Planning and Response Commission, 1991

INCIDENT COMMAND SYSTEM (ICS) An organized system of roles, responsibilities, and standard operating procedures used to manage and direct emergency operations. HAZARDOUS MATERIALS EMERGENCY RESPONSE GLOSSARY OF STANDARDIZED TERMS, State of California's Chemical Emergency Planning and Response Commission, 1991

INDIVIDUAL STORAGE AREA ...means the area occupied by piles, bin boxes, racks or shelves, including subsidiary aisles providing access to the stored products, which is separated from the adjacent storage by aisles not less than 2.4 m in width. (Ontario Fire Code 1996)

INDUSTRIAL OCCUPANCY (Group 'F') ...means the occupancy or use of a building or part thereof for assembling, fabricating, manufacturing, processing, repairing or storing of goods and materials. (Ontario Fire Code 1996)

INERT Descriptive of condition of a device that contains no explosive, pyrotechnic or chemical agent. (Hydro Cut General Terminology Resource Information)

INERT GAS Inert gas or noble gas, any of the elements in group 0 of the Periodic Table. In order of increasing atomic number, they are Helium, Neon, Argon, Krypton, Xenon, and Radon . Sometimes called the rare gases (although argon makes up 1% of the atmosphere), they are colorless, odorless, and tasteless. Inert gases have very low chemical activity because their outermost, or valence, electron is complete, containing two electrons in the case of helium and eight in the remaining cases. (Hydro Cut General Terminology Resource Information)

INERTIA Inertia, in physics, the resistance of a body to any alteration in its state of Motion, i.e., the resistance of a body at rest to being set in motion or of a body in motion to any change of speed or direction of motion. Mass. (Hydro Cut General Terminology Resource Information)

INFRARED RADIATION Infrared radiation is Electromagnetic Radiation having a wavelength in the range of 750 to 1,000,000 nanometers, thus occupying that part of the electromagnetic spectrum with a frequency less than that of red visible Light and greater than that of Microwaves. Infrared radiation is thermal, or heat, radiation, and is produced by any body having a temperature above absolute zero. It has many of the same properties as visible light, such as being reflected or refracted. (Hydro Cut General Terminology Resource Information)

INITIAL FIRE ATTACKExcept in the largest fire departments, it is not expected that the on-duty force will be adequate to apply the maximum fire flow that may be needed. Normally, beyond a certain capability for initial attack, use of off-duty personnel and response from neighboring fire departments will be required to apply peak fire flows. The ability to hold fires in check until adequate forces can be mobilized often is a critical factor in the extent of the loss. In practically all instances, the prudent minimum initial attack capability on initial response should be sufficient men and equipment to promptly apply a hose stream capacity of 400 to 500 gpm as outlined in NFPA Standard No. 197 "Training for Initial Fire Attack" For operations from more than one position, at least twice as great initial response may be desirable to quickly apply hand lines with a total capacity of 1000 gpm. [Kimball 1969]

INITIAL INCIDENT REPORTThe initial incident report is not intended to be the complete fire record nor to serve as a guide for developing the ignition sequence or the various details pointing to those factors causing or contributing to the ignition or extension of the fire. in addition, it is not intended to provide all of the known fire incident information supportive to a continuing or in-depth investigation. It should also be noted that since the initial report is not intended as a final or complete report, the ignition sequence information reported should only be considered as most probable based on information available to the reporting officer at the time. Any information which later investigation shows to be inaccurate should be corrected on the appropriate reports. [NFPA 901-1981]

INSPECTExamine for a deviation. (Benner 1997)

INSPECT ...means physical examination to determine that the device or system will apparently perform in accordance with its intended function. (Ontario Fire Code 1996)

INSPECTIONS (fire prevention)Fire prevention inspections are conducted by state or local fire department personnel in compliance with laws and ordinances which usually require specific fire inspections. Occupancies normally inspected include places of public assembly, educational, institutional, residential (except the interior of dwellings), mercantile, business, industrial, manufacturing, storage, and special-hazards structures. In addition to such mandatory inspections, the fire department may also conduct voluntary fire inspections, such as home fire safety surveys. [NFPA Handbook 1991]

INSTITUTIONAL OCCUPANCY (Group 'B') ...means the occupancy or use of a building or part thereof by persons who require supervisory care, medical care or medical treatment or by persons who are under restraint for correctional purposes and are incapable of self preservation because of security measures not under their control. (Ontario Fire Code 1996)

INTERNATIONAL AIR TRANSPORT ASSOCIATION (IATA)An association of air carriers which develop guidelines for transportation of cargo. HAZARDOUS MATERIALS EMERGENCY RESPONSE GLOSSARY OF STANDARDIZED TERMS, State of California's Chemical Emergency Planning and Response Commission, 1991

INTERNATIONAL CIVIL AVIATION ORGANIZATION (ICAO)Develops the principles and techniques of international air navigation and fosters the planning and development of international air transport so as to insure safe and orderly growth. HAZARDOUS MATERIALS EMERGENCY RESPONSE GLOSSARY OF STANDARDIZED TERMS, State of California's Chemical Emergency Planning and Response Commission, 1991

INTUMESCENT COATINGA protective chemical coating, which, when heated, internally generates gases and expands, resulting in a thermally insulating crust that contains cavities. [Friedman 1989]

INVESTIGATE (to)To observe and inquire into what happened; examine systematically. (Benner 1997)

INVESTIGATING ACCIDENTS... the reporting and investigation of accidents and dangerous occurrences; (Source: Termium 1994)

INVESTIGATIONA process conducted for the purpose of accident prevention which includes the gathering and analysis of information, the drawing of conclusions, including the determination of cause(s) and, when appropriate, the making of safety recommendations. Term and definition standardized by ICAO. (Source: Termium 1994)

INVESTIGATION QUALITY CONTROLSTraditional investigations lack objective quality control procedures for either the investigation work products or the investigation process itself. Quality of work products is controlled primarily by one of several variations of the peer review procedures, and validity is decided by power of persuasion in what is essentially an adversarial process. A second general approach is the "fly-fix-fly" approach, where conclusions are tested by repeating the experiment or occurrence or simulating it, and determining from the outcome if the investigation findings "reproduced" the occurrence. Quality control of the investigation process is similarly determined. In the absence of objective quality control criteria, and procedures to apply those criteria, consistent investigation performance and outputs should not be expected. The multilinear events sequence-based (MES-based) investigation process provides new opportunities for controlling the quality of the INVESTIGATION and its WORK PRODUCTS, including the description and explanation of what happened, recommendations flowing from the investigation, investigation reports, and effectiveness of the control actions implemented. The primary quality control vehicles are the MES-based Worksheet and work products developed from that worksheet. These Investigation Quality Control (IQC) procedures constitute an essential element of the MES-based investigation process, and provide a way to check reports resulting from other methods. (Ludwig Benner, MES Guide 10, GUIDANCE FOR PERFORMING INVESTIGATION QUALITY CONTROL TASKS, 1998)  

IRONY / expression of something which is contrary to the intended meaning; the words say one thing but mean another.
*Yet Brutus says he was ambitious; And Brutus is an honourable man. Shakespeare, Julius Caesar (A Glossary of Rhetorical Terms with Examples, Ross Scaife)

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