BOF ch 4 Flashcards

A substance remains chemically the same but changes in size, shape, or appearance.

A substance changes from one type of matter into another, such as two or more substances combining to form compounds.

A chemical reaction involving the combination of an oxidizer such as oxygen in the air with other materials.

Represents the amount of energy that an object can release at some point in the future.

Stored energy

The energy that a moving object possesses.

Unit of measurement for heat.

The movement of two surfaces against each other creates heat of friction that generates heat and or sparks.

The transfer of heat through and between solids

occurs when a material is heated as a result of direct contact with a heat source.

The heat transfer of thermal energy by the circulation or movement of a fluid

The transmission of energy as electromagnetic waves such as light waves, radio waves, or x-rays without an intervening medium

Fatal condition caused by severe oxygen deficiency and an excess of carbon monoxide and or other gases in the blood

Ignition of combustion by heat but without a spark or flame

NFPA 921-2011- guide for fire and explosion investigations

The lowest temp at which a combustible material ignites in air without a spark or flame.

Explosion or rapid burning of superheated gases that occurs when oxygen is introduced into an oxygen-depleted confined space.

The tendency or capacity of a liquid or gas to remain afloat or rise

Fuels in which the energy of combustion derives principally from carbon. materials such as wood, cotton, coal, or petroleum.

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.

Extinguishment of a fire by interruption of the chemical chain reaction

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

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

Chemicals reaction in which a substance absorbs heat.

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

To draw in and transport solid particles or gases by the flow of a fluid

the drawing in and transporting of solid particles or gases by the flow of a fluid.

chemical reaction between two or more materials that changes the materials and produces heat.

A fire ignited in fuel packages or buildings that are remote from the initial fuel package or building of origin

Temp at which a liquid fuel produces sufficient vapors to support combustion once the fuel ignites.

model of the four elements/conditions required to have a fire. four sides represents fuel, heat, oxygen, and self-sustaining chemical chain reaction.

used to explain the conditions/ elements necessary for combustion. representing heat, oxygen, and fuel

range between the upper flammable limit and lower flammable limit in which a substance can ignite

Minimum temperature at which a liquid gives off enough vapors to form an ignitable mixture with air near the surface of the liquid

rapid transition from the growth stage to the fully developed stage

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.

electrically charged, highly reactive parts of molecules released during combustion reactions

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

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.

total amount of thermal energy that could be generated by the combustion reaction if a fuel were completely burned.

the measurement of the rate of heat transfer to or from a surface, typically expressed in kilowatts per square meter

total amount of heat released per unit time.

petroleum-based organic compound that contains only hydrogen and carbon, ma also be used to describe those materials in a fuel load.

result of inefficient combustion of a fuel, the less efficient the combustion.

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.

unit of work or energy in the international system of units. terms of mechanical energy.

possessed by a moving object because of it's motion.

Lower limit at which a flammable gas or vapor will ignite and support combustion

anything that occupies space and has mass

materials that are capable of being mixed in all properties

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.

moment a mixture of fuel and oxygen encounters an external heat source with sufficient heat or thermal energy to start the combustion reaction

flammable liquids that have an attraction to water, much like a positive magnetic pole attracts a negative pole

stored energy possessed by an object that can be released in the future to perform work once a released

the chemical decomposition of a solid material by heating. precedes combustion of a solid fuel.

fuel that is being oxidized or burned during combustion

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.

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

Degree to which a solid, liquid, or gas dissolves in a solvent

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

initiation of combustion of a material by an internal chemical or biological reaction that has produced sufficient heat to ignite the material.

the propensity of a material to conduct heat within it's volume. measured in energy transfer over distance per degree of temperature

Kinetic energy associates with the random motions of the molecules of a material or object

often used interchangeably with heat and heat energy

the point at which two regions that are in thermal contact no longer transfer heat between them because they have reached the same temperature

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

upper limit at which a flammable gas or vapor will ignite; above this limit the gas or vapor is too rich to burn.

weight of pure vapor or gas compared to the weight of an equal volume or dry air at the same temperature and pressure.

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

the heat release rate or growth is limited by the amount of oxygen available to the fire

the SI unit of power or rate of work equal to 1 joule per second