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DANGEROUS GOODS ... means those products or substances which are regulated by the Transportation of Dangerous Goods Act (Canada) and its Regulations. (Ontario Fire Code 1996)

DATA LANGUAGE The consistent language used by investigators to report observations they make during investigations. One of the critical requirements of observation in scientific method is that it be REPLICABLE, i.e., reported by others who are also able to see and record it. Replicability demands a consistent language to report observations. This is what is meant by the DATA LANGUAGE of science. One basic mishap investigation problem has been lack of a UNIVERSAL DATA LANGUAGE for observations reported by investigators. (From STEP Handbook, © 1991 Ludwig Benner, Jr.)

DEGREE OF COMBUSTIBILITY The chemistry of a material generally is the key to its degree of combustibility. [Friedman 1989]

DEMOLITION ...means the doing of anything in the removal of a building or any material part thereof. (Ontario Fire Code 1996)

DEVIATION An event that differs from what was intended or expected. (Benner 1997)

DIFFUSION FLAME A flame in which the fuel vapors and oxygen diffuse into each other as they burn, such as candle flame. [Friedman 1989]

DISTILLED BEVERAGE ALCOHOL ... means a beverage that is produced by fermentation and contains more than 20 per cent by volume of water-miscible alcohol. (Ontario Fire Code 1996)

DISTILLERY ...means a process plant where distilled beverage alcohols are produced, concentrated or otherwise processed, and includes facilities on the same site where the concentrated products may be blended, mixed, stored or packaged. (Ontario Fire Code 1996)

DRY CHEMICAL Any of several powders used to extinguish fires. [Friedman 1989]

DRY ICE Solid carbon dioxide. [Friedman 1989]

DWELLING UNIT ...means a suite operated as a housekeeping unit, used or intended to be used as a domicile by one or more persons and usually containing cooking, eating, living, sleeping and sanitary facilities. (Ontario Fire Code 1996)


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ENERGETICS OF CHEMICAL CHANGE Every chemical change is accompanied by a change of energy because the chemical energy of the reaction products is different from that of the reactants. This change usually is manifested in the form of heat energy , but also can include electrical energy (for electrochemical processes, as in batteries) or mechanical energy, where expansion or contraction or kinetic energy (motion) is involved (as in explosions). [Friedman 1989]

ENERGY UNITS The basic SI unit of energy is the joule (J ). A joule is the quantity of energy expended when a force of 1 newton pushes something a distance of 1 meter. Thermal energy as well as mechanical energy can be expressed in joules. One joule equals 0.239 calorie, or 4.187 joules equal 1 calorie. (A calorie is the energy needed to heat one gram of water 1C; a dietetician's "calorie" is actually 1000 calories.) Electrical energy can be expressed in joules; one joule is 1 watt-second. One megajoule (1,000,000 joules) is 0.278 kilowatt-hour. (for example, if a power of 1 kilowatt is released in an electric iron for 0.278 hour, than 1 megajoule of thermal energy has been released.) In English units, energy is expressed in foot-pounds or BTU s. One foot-pound is equal to 1.355 joule, and 1 BTU is equal to 1055 joules or 252 calories. [Friedman 1989] ENTRAINMENT  The process in which a slow-moving or stagnant fluid mixes into an adjacent turbulent flow. For example, a rising fire plume entrains surrounding air. [Friedman 1989]

EUPHEMISM / substitution of an agreeable or at least non-offensive expression for one whose plainer meaning might be harsh or unpleasant.
*When the final news came, there would be a ring at the front door -- a wife in this situation finds herself staring at the front door as if she no longer owns it or controls it--and outside the door would be a man... come to inform her that unfortunately something has happened out there, and her husband's body now lies incinerated in the swamps or the pines or the palmetto grass, "burned beyond recognition," which anyone who had been around an air base very long (fortunately Jane had not) realized was quite an artful euphemism to describe a human body that now looked like an enormous fowl that has burned up in a stove, burned a blackish brown all over, greasy and blistered, fried, in a word, with not only the entire face and all the hair and the ears burned off, not to mention all the clothing, but also the hands and feet, with what remains of the arms and legs bent at the knees and elbows and burned into absolutely rigid angles, burned a greasy blackish brown like the bursting body itself, so that this husband, father, officer, gentleman, this ornamentum of some mother's eye, His Majesty the Baby of just twenty-odd years back, has been reduced to a charred hulk with wings and shanks sticking out of it. Tom Wolfe, The Right Stuff (A Glossary of Rhetorical Terms with Examples, Ross Scaife)

EVENT One actor + one action; the basic investigative and analytical building block (event unit / item). (See also MES concepts and logic tools) (Benner 1998)

EXFILTRATION Air flow outward through a wall, leak, membrane, etc. [ASHRAE Guide and Data Book 1963]

EXHAUST (see Ventilation) Rapid generation of steam within a confined space causes the original atmosphere (heated smoke and air) to be displaced by an atmosphere of steam. ... The major movement of this displacement is always upward and outward. ... If the volume of steam generated within the space exceeds the net atmospheric volume of the space, the EXCESSIVE steam will be forced out by way of the same channels and OPENINGS through which the original atmosphere was exhausted. [Layman 1955]

EXIT ... means that part of a means of egress, including doorways, that leads from the floor area it serves to a separate building, an open public thoroughfare or an exterior open space protected from fire exposure from the building and having access to an open public thoroughfare. (Ontario Fire Code 1996)

EXPERT WITNESS A person who possesses special knowledge in a particular field by virtue of specialized skill, expertise, training, and/or education, and who is adjudged qualified to render expert opinions in that field in court proceedings. [Fire Cause Determination, IFSTA 1986]

EXTINGUISHMENT Combustion requires a high temperature, and the reactions must proceed fast enough at this high temperature to generate heat as fast as it is dissipated, so that the reaction zone will not cool down. In some cases, only a modest additional loss of heat is needed to tip the balance toward extinguishment. Extinguishment can be accomplished either by cooling the gaseous combustion zone or the solid or liquid combustible. In the latter case, the cooling prevents the production of combustible vapors . (This is probably the primary mode of action when a wood fire is extinguished by applying water.) [Friedman 1989]

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FAILURE Distortion, breakage, deterioration, or other fault in a structure, component, or system resulting in unsatisfactory performance of the function for which it was designed. [NFPA 921 - 1992]

FAILURE ANALYSIS A logical, systematic examination of an item, component, or assembly, and its place and function in a system, to identify and analyze the probability, causes, and consequences of potential and real failures. [NFPA 921 - 1992]

FARM BUILDING ...means a building or part thereof associated with and located on land devoted to the practice of farming, and used primarily for the housing of equipment or livestock or the production, storage or processing of agricultural and horticultural produce or feeds, but is not used for residential occupancy. (Ontario Fire Code 1996)

FIRE ANALYSIS The process of determining the origin, cause, and responsibility as well as the failure analysis of a fire or explosion. [NFPA 921 - 1992]

FIRE ATTACK The standard 250 gpm hose stream normally is applied with a hand line of 2,5 inch fire hose. Normally, three men should be provided to run the hose to the desired point of operation and direct this stream. [Kimball 1969]

FIREBRAND A flaming or smoldering airborne object emerging from a fire, which can sometimes ignite remote combustibles. [Friedman 1989]

FIRE CAUSE The circumstances or agencies that bring a fuel and an ignition source together with proper air or oxygen. [NFPA 921 - 1992]

FIRE CAUSE Agency or circumstance that started a fire or set the stage for one to start; source of a fire's ignition. [Fire Cause Determination, IFSTA 1986]

FIRE CAUSE DETERMINATION, IFSTA 1986 This manual is not intended to address the many complex areas of criminal investigation that are found in other fire investigation books, but to give fire fighting personnel the basic information they need for reports, to help them recognize when the services of an investigator are needed, and to help them to assist the investigator. ...ONLY RARELY WILL THE INVESTIGATOR ALSO BE UNABLE TO FIND THE CAUSE. EVEN COLLAPSED AND "TOTALLY DESTROYED" BUILDINGS HAVE SECRETS TO YIELD . [Fire Cause Determination, IFSTA 1986]

FIRE COMPARTMENT ... means an enclosed space in a building that is separated from all other parts of the building by enclosing construction that provides a fire separation having a required fire-resistance rating. (Ontario Fire Code 1996)

FIRE DAMPER ...means a closure that consists of a damper installed in an air distribution system or in a wall or floor assembly that is normally held in the open position and that is designed to close automatically in the event of a fire in order to maintain the integrity of the fire separation. (Ontario Fire Code 1996)

FIRE DEFENSE MANAGEMENT (see also Uniform Coding) In 1938, a fire reporting system prepared by NFPA was published by the International City Manager's Association. This system served as a start toward the uniform reporting of fire incident information. From 1963 to 1969, the Committee strived to develop a uniform language for fire defense management ... [NFPA 901-1981]

FIRE DEPARTMENT ...means a group of firefighters authorized to provide fire protection services by a municipality, group of municipalities or by an agreement made under section 3 of the Fire Protection and Prevention Act. (Ontario Fire Code 1996)

FIRE DETECTOR ...means a device which detects a fire condition and automatically initiates an electrical signal to actuate an alert signal or alarm signal and includes heat detectors and smoke detectors. (Ontario Fire Code 1996)

FIRE EXTINGUISHMENT The cessation of combustion. [Friedman 1989]

FIRE FIGHTING Fire fighting involves the manual control and extinguishment of fires. ... manning of fire apparatus, .2 the rate at which the fire force may be expected to apply water to fires. THE RATE OF WATER APPLICATION IS TERMED "FIRE FLOW" (...the resultant "fire attack" capability). (Warren Y. Kimball, Manning for Fire Attack, NFPA, Boston,1969)

FIRE FLOW : FIRE FLOW AS A MEASURE OF PERFORMANCE . As water is the principal and most universal extinguishing agent employed by fire departments, extinguishing capacity is measured in gallons of water applied per minute. Ordinarily with large flows a substantial part of the water is applied in the form of heavy streams. In addition to pumpers actually employed in applying the fire flow, one or more additional units may be needed ... in the event of mechanical failure of an operating pumper or sudden extension of the fire. Merely having the fire flow available and the necessary pumping capacity ... does not assure effective fire protection. Knowledge and equipment is also needed to effectively apply the water. Rate of water application per man employed may average approximately 80 gpm. Traditional underwriters' recommendations for fire department pumping capacity are extremely conservative. They ask only for available pumping capacity to equal two-thirds of the fire flow required in the area. Under fire fighting conditions pumpers on the average deliver not much over half to two-thirds of their rated capacities when employed at fires requiring a high fire flow. Fire departments desiring to be able to deliver maximum fire flow per man and per unit employed on the fireground will need to give attention to thorough training in the movement and application of water using pumps, hose and nozzles in an efficient manner. Fire flows by pumpers at significant working fires seldom exceeds an average of between 500 and 600 gpm per pumper employed. For effective fire department operations a number of other tasks must be performed simultaneously with the work of allying the desired fire flow; the effectiveness of the application of hose streams MAY DEPEND in large measure upon their successful completion. [Kimball 1969]

FIREGROUND As long as all of the basic requirements of the fireground are met, it is presumptuous to say that one solution is preferable to the other without knowing the requirements of the area served and the reasons for the particular type of response. In most communities, large fires and emergencies tend to be extremely infrequent. Effective fireground operations involve two fundamentals : .1 carefully engineered equipment components, .2 personnel to deliver specified fire attack capabilities which individual items of equipment are designed to provide. The fire fighting capability depends upon a complete systems approach and not the mere massing of random forces when an emergency occurs (fire companies competing for water). SOLUTIONS WHICH ARE DIFFICULT OR NEEDLESSLY COMPLICATED SHOULD NOT BE SELECTED FOR STANDARD PROCEDURES. [Kimball 1969]

FIRE INSPECTOR Fire prevention specialist and/or fire or arson investigator. [Fire Cause Determination, IFSTA 1986]

FIRE INVESTIGATION The process of determining the origin, cause, and development of a fire or explosion.[NFPA 921 -1992]

FIRE INVESTIGATION The thorough investigation of fires is an integral part of the fire department's commitment to public safety. Fire investigation includes two areas: fire cause determination, and investigation of criminal actions which may have contributed to a fire. [NFPA Handbook 1991]

FIRE INVESTIGATION (training) All investigators should be trained in the basics of fire scene investigation, which include adequate documentation of the scene, origin determination, and cause determination. Specific emphasis should be placed on techniques for debris removal and scene reconstruction. Although much of this knowledge can be gained by studying text materials, there is no substitute for field experience. [NFPA Handbook 1991]

FIRE PREVENTION (methods) Fire prevention includes all fire service activity that decreases the incidence of uncontrolled fire. Usually, fire prevention methods used by the fire service focus on inspection, which includes engineering and code enforcement, public fire safety, education, and fire investigation. [NFPA Handbook 1991]

FIRE-PROTECTION RATING ...means the time in hours or fraction thereof that a closure, window assembly or glass block assembly will withstand the passage of flame when exposed to fire under specified conditions of test and performance criteria, or as otherwise prescribed in the Building Code. (Ontario Fire Code 1996)

FIRE RESISTANCE ...means the property of a material or assembly in a building to withstand fire or give protection from it and is characterized by the ability of the material or assembly to confine a fire or to continue to perform a given structural function or both. (Ontario Fire Code 1996)

FIRE-RESISTANCE RATING ...means the time in hours or fraction thereof that a material or assembly of materials will withstand the passage of flame and the transmission of heat when exposed to fire under specified conditions of test and performance criteria, or as determined by extension or interpretation of information derived therefrom as prescribed in the Building Code. (Ontario Fire Code 1996)

FIRE SCENE RECONSTRUCTION The process of recreating the physical scene during fire scene analysis through the removal of debris and the replacement of contents or structural elements in the pre-fire positions. [NFPA 921 - 1992]

FIRE SEPARATION ... means a construction assembly that acts as a barrier against the spread of fire and may or may not have a fire-resistance rating or a fire-protection rating. (Ontario Fire Code 1996)

FIRE SPREAD !!!

The movement of fire from one place to another .[NFPA 921 - 1992/2001] (stands for fire propagation. See instead: Convection, Radiation, Conduction)

FIRE STOP ...means a draft-tight barrier within or between construction assemblies that acts to retard the passage of smoke and flame. (Ontario Fire Code 1996)

FIRE-STOP FLAP ...means a device intended for use in horizontal assemblies that are required to have a fire-resistance rating and incorporate protective ceiling membranes and that operates to close off a duct opening through the membrane in the event of a fire. (Ontario Fire Code 1996)

FIRE SUPPRESSION

Either extinguishment of a fire as a result of fire fighting activity, or reduction of the combustion rate to a small enough value so that the fire is under control. (A large fire, after being suppressed, could continue to smolder for days.) [Friedman 1989]

FIREWALL ...means a fire separation of noncombustible construction that subdivides a building or separates adjoining buildings to resist the spread of fire that has a fire-resistance rating as prescribed in the Building Code and that has structural stability to remain intact under fire conditions for the required fire-rated time. (Ontario Fire Code 1996)

FIRST ALARM RESPONSE First alarm response must be sufficient to meet the basic tactical requirements which may be anticipated in the district in which the fire occurs. In general, a first alarm response of 12 to 15 officers and men with appropriate apparatus is likely to be desirable to quickly apply initial hose streams along with necessary truck work and command supervision. In all cases, not less than two pieces of suitable motorized fire apparatus should respond. The important thing is the total tactical capability provided. For example in a residential suburb, there may be a fire department entirely adequate to handle fires in residences and associated buildings of moderate hazard. This fire department has ample reserve apparatus for emergency situations and is backed up by good mutual aid arrangements TO DEAL WITH ABNORMAL FIRE PROTECTION REQUIREMENTS. IT HAS LONG BEEN RECOGNIZED THAT NO COMMUNITY CAN AFFORD TO MAINTAIN A FIRE DEPARTMENT POWERFUL ENOUGH TO HANDLE ANY FIRE SITUATION THAT MAY OCCASIONALLY ARISE. [Kimball 1969]

FIRST-IN Firefighters initially attacking a fire - usually the first to arrive at the fire scene.[Fire Cause Determination, IFSTA 1986]

FIRST STOREY ...means the storey with its floor closest to grade and having its ceiling more than 1.8 m above grade. (Ontario Fire Code 1996)

FLAME The luminous portion of burning gases or vapors.[NFPA 921 - 1992]

FLAME (characteristics) Flame height is controlled by the rate of diffusional mixing with oxygen rather than by chemical reaction rates. ...the upward flow is driven entirely by buoyancy. The height of a buoyancy-dominated turbulent diffusion flame, more often encountered in a fire, is correlated most successfully in terms of the convective heat- release rate of the flame, which is expressed in kilowatts . [Friedman 1989]

FLAME (flaming combustion) A flame is a gaseous oxidation reaction, which occurs in a region of space much hotter than its surroundings and generally emits light. Familiar examples include the yellow flame of a candle and the blue flame on a gas burner. [Friedman 1989]

FLAME-SPREAD RATING ...means an index or classification indicating the extent of spread of flame on the surface of a material or an assembly of materials as determined in the Building Code. (Ontario Fire Code 1996)

FLAME TEMPERATURE Most combustibles, when burned with just the stoichiometric amount of air, under conditions where no heat is lost, will produce flames at temperatures from 2100 to 2300 K, and chemical equilibrium would be achieved in such flames. In fires , however, combustion often occurs with a yellow luminous flame because of tiny, hot carbon particles that form and radiate heat energy. As much as 30-40% of the heat of combustion can be lost from such a flame because of this radiation. Consequently, the flame temperature often will be below 2000 K, and the combustion gases will become diluted with air and cooled before equilibrium can be reached. THIS PHENOMENON CAN CAUSE DANGEROUS CONCENTRATIONS OF CARBON MONOXIDE, EVEN IF AN EXCESS OF OXYGEN IS PRESENT AROUND THE FLAME. [Friedman 1989]

FLAMES (types of GASEOUS ) Flames can be categorizes as premixed flames or diffusion flames (fuel gas mixed with oxygen before or during combustion). In addition, they can be categorized as laminar or turbulent flames, as well as stationary or propagating flames. Any combination is possible... ... 9.5% methane (CH4) by volume and 90.5% air, thoroughly mixed is a stoichiometric mixture, according to the equation : CH4 + 2O2 -> CO2 + 2H2O. If an ignition source, say a spark, is provided in the center, then a spherical flame will form around the spark and spread radially outward at about 3 meters per second (10 feet per second). If less than 5% or more than 15% of methane is present the mixture would be too far from stoichiometric, and no ignition would occur. For combustible mixtures with greater than 9.5% methane ("rich mixtures"), there would be insufficient oxygen to completely oxidize the CH4 to CO2 and H2O, and the products would include some CO, some H2, and, for very "rich" mixtures, some solid carbon (soot). This type of flame, whether stoichiometric or not, is a premixed flame . The contrasting type of flame is a diffusion flame . Assume that there is a cloud of methane, resulting from a sudden release of gas from a tank, surrounded by air, but mixing has not occurred yet except in a thin zone at the interface between methane and air. If an ignition source is provided at this interface, then combustion will spread rapidly over the surface of the cloud. Subsequently, the bulk of the methane within the cloud will burn more slowly, as air and methane interdiffuse. Meanwhile, the hot burning ball of gas will rise. The flame will be yellow . In summary, premixed flames burn more rapidly than diffusion flames , and the chemistry is different (blue flames versus yellow flames ). Large flames or flames burning with high velocity flows generally are turbulent . On the other hand, small flames (such as candle flames or the flame cones on a domestic gas burner) generally are laminar , i.e. the streamlines are smooth and the fluctuations are absent or negligibly small. The presence of turbulence in a flame enhances heat transfer and mixing, and can even affect the chemistry. Accordingly, rates of combustion are considerably higher in turbulent than in laminar flames. As a general rule, a diffusion flame taller than 0.3 meter (1 foot) will be turbulent , while a diffusion flame shorter than 0.1 meter (4 inches) will be laminar , unless a high velocity jet is involved. [Friedman 1989]

FLAMMABLE LIQUID ... means a liquid having a flash point below 37.8 C and having a vapour pressure not more than 275.8 kPa (absolute) at 37.8 C as determined by ASTM D 323, "Vapor Pressure of Petroleum Products (Reid Method)". (Ontario Fire Code 1996)

FLASH FIRE A fire that spreads with extreme rapidity, such as one that races over dust, over the surface of flammable liquids, or through gases.[NFPA 921 - 1992]

FLASHOVER A stage in the development of a contained fire in which all exposed surfaces reach ignition temperatures more or less simultaneously and fire spreads rapidly throughout the space.[NFPA 921 - 1992]

FLASHOVER For burning in a room, flashover is the often-sudden transition from local burning to widespread burning of all exposed combustibles. After flashover, flames might be projecting out a door or window. [Friedman 1989]

FLASHOVER & RURAL FIRE PROTECTION (evaluation and planning of public fire protection) To be even minimally effective in controlling a fire, the initial responding apparatus should reach the emergency scene in time to prevent "flashover " (a very rapid spreading of the fire due to the heating of room contents and other combustibles). (Fire Protection Handbook, 17th Edition, NFPA, Quincy, 1991 / NFPA Handbook 1991)

FLASH POINT ... means the minimum temperature at which a liquid within a container gives off vapour in sufficient concentration to form an ignitable mixture with air near the surface of the liquid. (Ontario Fire Code 1996)

FLOOR AREA ... means the space on any storey of a building between exterior walls and required firewalls and includes the space occupied by interior walls and partitions, but does not include exits and vertical service spaces that pierce the storey. (Ontario Fire Code 1996)

FLUE ...means an enclosed passageway for conveying flue gases. (Ontario Fire Code 1996)

FLUE PIPE ...means the pipe connecting the flue collar of an appliance to a chimney. (Ontario Fire Code 1996)

FORENSIC SCIENCE Application of scientific procedures to the interpretation of physical events, such as those that occur at fire scenes; the art of reconstructing past events and then explaining that process and findings to investigators and triers of facts; criminalistics. [Fire Cause Determination, IFSTA 1986]

FUEL CONTROLLED FIRE A fire in which the heat release rate and growth rate are controlled by the characteristics of the fuel, i.e., quantity and geometry. Adequate air for combustion is available.[NFPA 921 - 1992]

FUEL DISPENSING STATION ...means any premises at which flammable or combustible liquids are dispensed from fixed equipment into the fuel tank of a motor vehicle or watercraft. (Ontario Fire Code 1996)

FURNACE ... means a space-heating appliance that uses warm air as the heating medium and that usually has provision for the attachment of ducts. (Ontario Fire Code 1996)


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