front 1 Physical change occurs when? | back 1 A substance remains chemically the same but changes in size, shape, or appearance. |
front 2 Chemical reaction occurs when? | back 2 A substance changes from one type of matter into another, such as two or more substances combining to form compounds. |
front 3 Oxidation | back 3 A chemical reaction involving the combination of an oxidizer such as oxygen in the air with other materials. |
front 4 Potential energy | back 4 Represents the amount of energy that an object can release at some point in the future. Stored energy |
front 5 Kinetic energy | back 5 The energy that a moving object possesses. |
front 6 BTU | back 6 Unit of measurement for heat. |
front 7 Mechanical energy | back 7 The movement of two surfaces against each other creates heat of friction that generates heat and or sparks. |
front 8 Conduction | back 8 The transfer of heat through and between solids occurs when a material is heated as a result of direct contact with a heat source. |
front 9 Convection | back 9 The heat transfer of thermal energy by the circulation or movement of a fluid |
front 10 Radiation | back 10 The transmission of energy as electromagnetic waves such as light waves, radio waves, or x-rays without an intervening medium |
front 11 Asphyxiation | back 11 Fatal condition caused by severe oxygen deficiency and an excess of carbon monoxide and or other gases in the blood |
front 12 Autoignition | back 12 Ignition of combustion by heat but without a spark or flame NFPA 921-2011- guide for fire and explosion investigations |
front 13 Autoignition temps | back 13 The lowest temp at which a combustible material ignites in air without a spark or flame. |
front 14 Back draft | back 14 Explosion or rapid burning of superheated gases that occurs when oxygen is introduced into an oxygen-depleted confined space. |
front 15 Buoyant | back 15 The tendency or capacity of a liquid or gas to remain afloat or rise |
front 16 Carbon-based fuels | back 16 Fuels in which the energy of combustion derives principally from carbon. materials such as wood, cotton, coal, or petroleum. |
front 17 Ceiling Jet | back 17 Horizontal movement of a layer of hot gases and combustion by-products from the center points of the plume, when a horizontal surface such as a ceiling redirects the vertical development of the rising plume. |
front 18 Chemical flame inhibition | back 18 Extinguishment of a fire by interruption of the chemical chain reaction |
front 19 Combustion | back 19 A chemical process of oxidation that occurs at a rate fast enough to produce heat and usually light in the form of either a glow or flame |
front 20 Compartmentation | back 20 The way that the arrangement of compartments creates or does not create series of barriers designed to keep flames, smoke, and heat from spreading from one room or floor to another |
front 21 Endothermic reaction | back 21 Chemicals reaction in which a substance absorbs heat. |
front 22 Energy | back 22 capacity to perform work, occurs when a force is applied to an object over a distance, or when a substance undergoes a chemical, biological, or physical transformation |
front 23 entrain | back 23 To draw in and transport solid particles or gases by the flow of a fluid |
front 24 entrainment | back 24 the drawing in and transporting of solid particles or gases by the flow of a fluid. |
front 25 Exothermic reaction | back 25 chemical reaction between two or more materials that changes the materials and produces heat. |
front 26 exposure fire | back 26 A fire ignited in fuel packages or buildings that are remote from the initial fuel package or building of origin |
front 27 Fire point | back 27 Temp at which a liquid fuel produces sufficient vapors to support combustion once the fuel ignites. |
front 28 Fire tetrahedron | back 28 model of the four elements/conditions required to have a fire. four sides represents fuel, heat, oxygen, and self-sustaining chemical chain reaction. |
front 29 Fire triangle | back 29 used to explain the conditions/ elements necessary for combustion. representing heat, oxygen, and fuel |
front 30 Flammable range | back 30 range between the upper flammable limit and lower flammable limit in which a substance can ignite |
front 31 Flash point | back 31 Minimum temperature at which a liquid gives off enough vapors to form an ignitable mixture with air near the surface of the liquid |
front 32 flash over | back 32 rapid transition from the growth stage to the fully developed stage |
front 33 Flow path | back 33 the space between at least one intake and one exhaust outlet. difference in pressure determines the direction of the flow of gases through this space. |
front 34 free radical | back 34 electrically charged, highly reactive parts of molecules released during combustion reactions |
front 35 fuel limited | back 35 Fire with adequate oxygen in which the heat release rate and growth rate are determined by the characteristics of the fuel, such as quantity and geometry |
front 36 fuel load | back 36 the total quantity of combustible contents of a building, space or fire area including interior finish and trim, expressed in heat units or the equivalent weight in wood. |
front 37 heat of combustion | back 37 total amount of thermal energy that could be generated by the combustion reaction if a fuel were completely burned. |
front 38 Heat flux | back 38 the measurement of the rate of heat transfer to or from a surface, typically expressed in kilowatts per square meter |
front 39 heat release rate | back 39 total amount of heat released per unit time. |
front 40 hydrocarbon fuel | back 40 petroleum-based organic compound that contains only hydrogen and carbon, ma also be used to describe those materials in a fuel load. |
front 41 incomplete combustion | back 41 result of inefficient combustion of a fuel, the less efficient the combustion. |
front 42 Isolated flames | back 42 flames in the hot gas layer that indicate the gas layer is within its flammable range and has begun to ignite, often observed immediately before a flashover. |
front 43 joule | back 43 unit of work or energy in the international system of units. terms of mechanical energy. |
front 44 Kinetic energy | back 44 possessed by a moving object because of it's motion. |
front 45 lower explosive limit | back 45 Lower limit at which a flammable gas or vapor will ignite and support combustion |
front 46 Matter | back 46 anything that occupies space and has mass |
front 47 Miscible | back 47 materials that are capable of being mixed in all properties |
front 48 neutral plane | back 48 level at a compartment opening where there is an equal difference in pressure exerted by expansion and buoyancy of hot smoke flowing out of the opening and the inward pressure of cooler ambient temp air flowing in through the opening. |
front 49 piloted ignition | back 49 moment a mixture of fuel and oxygen encounters an external heat source with sufficient heat or thermal energy to start the combustion reaction |
front 50 polar solvents | back 50 flammable liquids that have an attraction to water, much like a positive magnetic pole attracts a negative pole |
front 51 potential energy | back 51 stored energy possessed by an object that can be released in the future to perform work once a released |
front 52 pyrolysis | back 52 the chemical decomposition of a solid material by heating. precedes combustion of a solid fuel. |
front 53 reducing agent | back 53 fuel that is being oxidized or burned during combustion |
front 54 rollover | back 54 condition in which the unburned fire gases that have accumulated at the top of a compartment ignite and flames propagate through the hot gas layer or across the ceiling. |
front 55 self-heating | back 55 the results of exothermic reactions occurring spontaneously in some materials under certain conditions, whereby heat is generated at a rate sufficient to raise the temp of the material |
front 56 solubility | back 56 Degree to which a solid, liquid, or gas dissolves in a solvent |
front 57 specific gravity | back 57 Mass of a substance compared to the weight of an equal volume of water at a given temperature. less than 1 indicates a substance lighter than water. greater than 1 indicates a substance heavier than water |
front 58 spontaneous ignition | back 58 initiation of combustion of a material by an internal chemical or biological reaction that has produced sufficient heat to ignite the material. |
front 59 thermal conductivity | back 59 the propensity of a material to conduct heat within it's volume. measured in energy transfer over distance per degree of temperature |
front 60 thermal energy | back 60 Kinetic energy associates with the random motions of the molecules of a material or object often used interchangeably with heat and heat energy |
front 61 thermal equilibrium | back 61 the point at which two regions that are in thermal contact no longer transfer heat between them because they have reached the same temperature |
front 62 thermal layering | back 62 outcome of combustion in a confined space in which gases tend to form into layers, according to temperature, gas density, and pressure with the hottest gases found at the ceiling and the coolest gases at floor level |
front 63 upper explosive limit | back 63 upper limit at which a flammable gas or vapor will ignite; above this limit the gas or vapor is too rich to burn. |
front 64 vapor density | back 64 weight of pure vapor or gas compared to the weight of an equal volume or dry air at the same temperature and pressure. |
front 65 vapor pressure | back 65 the pressure at which a vapor is in equilibrium with it's liquid phase at a given temperature; liquids that have a greater tendency to evaporate have higher vapor pressures at a given temperature |
front 66 ventilation-limited | back 66 the heat release rate or growth is limited by the amount of oxygen available to the fire |
front 67 Watts | back 67 the SI unit of power or rate of work equal to 1 joule per second |