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| 13687572885 | Arson | the crime of setting fires for an unlawful or improper purpose | 0 | |
| 13687587420 | Arson can cause hundreds of millions of dollars annually in | increased insurance costs, increased taxes, loss of jobs, loss of business, and treatment of injuries | 1 | |
| 13687597621 | Arson is different from other crimes because | it is not always obvious a crime has occurred. A lot of fires look like they may be accidental, but in reality, they were planned and sometimes well thought out. | 2 | |
| 13687622083 | Arson is difficult to investigate because | fire destroys the evidence | 3 | |
| 13687627829 | Why do criminals turn to arson? | easy to light spreads quickly | 4 | |
| 13687642829 | The amount of damage an arsonist will be able to commit will depend on | how quickly firefighters arrive at the scene | 5 | |
| 13687647872 | Combustion | a chemical reaction in which a substance combines with oxygen and releases energy | 6 | |
| 13687653666 | Hydrocarbons | Compounds composed of only carbon and hydrogen | 7 | |
| 13687657916 | When any hydrocarbon undergoes complete combustion, the products are always | C02 and H20 | 8 | |
| 13687667489 | Energy released comes in various forms | heat, light, sound | 9 | |
| 13687671243 | exothermic reaction | a chemical reaction that releases energy to its surroundings | 10 | |
| 13687682813 | What must exist for combustion to happen? | the bonds within hydrocarbon and oxygen must be broken, a fuel, and oxygen | 11 | |
| 13687688197 | How can you break chemical bonds? | Heat (match, lighter, flint, spark, friction, cigarette) | 12 | |
| 13687705661 | Law od Conservation of Mass | the mass of the reactants must equal the mass of the products (the number of atoms of a given element in the reactants must equal the number of atoms in the products) | 13 | |
| 13687862621 | All hydrocarbons have similar properties. For example, | they burn easily | 14 | |
| 13687866332 | Fuel | a material that reacts with oxygen and releases energy when it burns | 15 | |
| 13687874508 | Fuels only burn in which state? | Vapor state | 16 | |
| 13687879321 | Flashpoint | The lowest temperature at which a fuel will give off enough vapor to mix with air and support combustion. | 17 | |
| 13687888364 | The lower the flashpoint | the greater the risk of fire | 18 | |
| 13687894850 | Ignition Temperature | The temperature that a fuel must reach before combustion can begin | 19 | |
| 13687904125 | An outside source is needed to ignite the fuel to its | ignition temperature | 20 | |
| 13687910421 | The ignition temperature is always higher than | the flashpoint | 21 | |
| 13687916921 | Pyrolysis | the decomposition of solid matter into gaseous products by heat | 22 | |
| 13687937330 | A solid fuel only burns when exposed to heat intense enough to | decompose the solid into gaseous products | 23 | |
| 13687945861 | Accelerant | a fuel source that increases the rate of combustion. It will make a fire burn at a higher temperature with an increased rate of speed. | 24 | |
| 13687964237 | Hydrocarbons are often used as | accelerants | 25 | |
| 13687975535 | Arsonists often suffer injuries or even death when setting fires because | accelerants ignite easily and explode readily | 26 | |
| 13688007171 | Investigators search arson crime scenes for | irregular burn patterns in debris as a sign for the presence of an ignitable liquid | 27 | |
| 13688018784 | The chain reaction for fire is: | as fire burns, the temperature increases as the temperature increases, the rate of reaction increases if the rate of reaction is increasing, then there are more gaseous products forming quicker; which is more fuel for the fire this will raise the temperature of the fire and so on | 28 | |
| 13688210411 | Stats info about where arson fries occur | Nearly half of arson fires are set outdoors 30% are in houses or other buildings 20% involve vehicles | 29 | |
| 13688243051 | Poor neighbourhoods compared to high-income neighbourhoods are | 14 times more likely for arson incidents | 30 | |
| 13688256927 | The problem with outdoor fires is they | tend to get out of control, they can destroy nearby housing and agriculture, and extreme climates like heat waves, droughts, and high winds can dramatically increase the size of the area consumed by a wildfire. | 31 | |
| 13688290207 | What are the motives for arson? | revenge, excitement, vandalism, crime concealment, and financial profit | 32 | |
| 13688302370 | Arson for Revenge | This is the leading motive for arson The events leading to this may be real or imagined and can take months or years before revenge is taken Common causes for revenge include disagreements or feelings of jealousy The goal is to cause physical or emotional harm (or commit murder) to someone by targetting the person's home, property, or place of business. Young arsonists typically set fire to school property, but since they are young and immature they are not planned well and do not conceal the crime well Most cases include disgruntled workers are angry because they have lost their job or have complaints against them | 33 | |
| 13688396787 | Arson for Excitement | This is the second leading motive for arsonists Not to be confused with a pyromaniac Arsonists set fires for a specific purpose, pyromaniac set fire for self-satisfaction | 34 | |
| 13688403479 | Pyromanic | a person who starts fires to relieve tension and typically includes feelings of satisfaction and indulgence afterward They have trends in their fire setting power, such as the same location, the same time, the same method | 35 | |
| 13688480071 | Why do arsonists set fires (for excitement)? Where do they typically set them? | boredom, the need for attention, the enjoyment they get from watching firefighters fight a blaze, and the "hero" effect (they save people or put out the fire) They set the fires in large outdoor spaces or in residential areas. They do this at in the night and under the influence of alcohol | 36 | |
| 13688588766 | Arson for Vandalism | Third leading arson motive Usually, two male youths They set fires because of family difficulties or peer pressure Usually, target abandoned buildings (they still attack schools, churches, homes, etc) Firefights still have to respond to these calls because homeless people often live in abandoned buildings. | 37 | |
| 13688628869 | Arson for Crime-Concealment | Fourth leading motive Set fires to places where they have committed a crime to destroy the evidence. These crimes could be anything from burglary to murder These fires are often set at night in unoccupied homes in places of business. | 38 | |
| 13688652906 | Arson for Profit | This is the least common motive for arson The target is usually the home or property of the arsonist themselves After the fire, they intend to file a fraudulent insurance claim to gain some profit This is commonly committed by adults, not youths since very few youth own property. Youth normally do not have financial pressure. The fires are usually set during the day in unoccupied homes or other buildings. | 39 | |
| 13688895106 | The typical arsonist: | Males under 18 Prior property offences Do it for revenge or profit Females do it for revenge Male arsonists tend to have problems with females Lack of remorse especially when setting fires in a trance-like state Lower to working class Absent or abusive fathers 90% have high school or less 22% are developmentally delayed | 40 | |
| 13688936419 | Typical Young Arsonist: | Exhibit interest between 3 and 10 years old motives are: boredom, curiosity, accidents, peer pressure, expressions of anger/stress A fire set by a young child is usually considered an accident or misbehaviour instead of arson the motives, the discipline, and counselling will determine if the child continues to set fires as they get older Fires are normally set in or near the family home If the fire is put out by the young arsonist, this means the child likely felt remorse and will try to conceal their actions. These children often respond to councilling Teenage arsonists often have an average intelligence, but do not progress in school due to learning difficulties or behavioural or psychological problems Teens often turn to arson to seek revenge or response to traumatic events like death or divorce. It becomes an outlet for their troubled emotions It is important to catch an arsonist while they are young to prevent future fires | 41 | |
| 13689123762 | Why is arson difficult to investigate? | arsonists are careful to avoid eyewitnesses fire destroys evidence | 42 | |
| 13689131334 | Circumstantial evidence | facts supporting evidence but no conclusive proof is available | 43 | |
| 13689149695 | Most of the evidence in arson cases is | circumstantial evidence | 44 | |
| 13689157729 | What is the leading cause of accidental fires? | careless smoking | 45 | |
| 13689161831 | Tell-tail signs arson has occurred | multiple points of origin point of origin near good supply of oxygen evidence burned quickly and for a long time empty fuel cans or other evidence of accelerants Unusual odours caused by the use of accelerants | 46 | |
| 13703228567 | what are the four classifications for the causes of fire? | natural, accidental, unknown, incendiary | 47 | |
| 13703232424 | incendiary | deliberately setting or causing fires | 48 | |
| 13703242240 | To classify a fire, investigators must first...? How do they do this? | try to locate the origin of the fire. To do this, photographs and diagrams of burn patterns are made and any physical evidence is collected and analyzed at the fire scene | 49 | |
| 13703267121 | The origin of the fire, along with other evidence, can determine | the cause and the time the fire was ignited | 50 | |
| 13703280564 | To prove that arson was the cause of the fire, investigators look for evidence in these four areas | Proof of incendiarism, proof of opportunity, proof of motive, circumstantial evidence | 51 | |
| 13703296251 | How to investigators look for "proof of opportunity"? | they look for anyone who had an opportunity to set the fire they will examine security and question anyone with access to the site before the fire. they will also ask for an alibi for the period of the fire if the alibis are confirmed, investigators will look for people who could have gained access illegally (they will now look for other evidence to help i.d suspects) | 52 | |
| 13703346958 | How do investigators determine "proof of motive"? | arsonists set fires for several reasons like revenge, vandalism, crime concealment, or financial gain if an owner gains from the fire, they will become a suspect. it is routine to look at the owner's insurance policies, history (ex. previous fires), and financial situation if a body is found the debris, the body may be a victim of the fire or a victim of another crime. the remains and scene are investigated to i.d the victim and the cause of death | 53 | |
| 13703406204 | circumstantial evidence in an arson related case | this type of evidence may help build a case but often falls short on conviction. Other types of evidence are often needed to convict someone, like witnesses. | 54 | |
| 13703426479 | Examples of evidence investigators may use to support their case | on-site fire or burglar detection systems are inspected for tampering background check on the caller licence plates in areas are checked previous police activity in the area hospitals in the area with burn victims accelerants being purchased locally | 55 | |
| 13703695936 | After a fire has been extinguished and arson investigators leave the site safety, police and fire department personnel control .... ? Why do they do this? | who enters and leaves the scene. they do this to prevent contamination | 56 | |
| 13703711405 | they store any physical evidence in a | evidence collection bin | 57 | |
| 13703721818 | all furniture and appliances are _______ they do this because _____? | placed back to their original position (based on a map drawn by the owners). they do this to examine and document every potential accidental ignition source or origin of arson in the rooms | 58 | |
| 13703752811 | fire will burn longer and therefore will have the most damage at what area? | the point of origin | 59 | |
| 13703756465 | the point of origin | The location where the fire started | 60 | |
| 13703763749 | physical evidence of the cause of the fire is found at or near | the point of origin | 61 | |
| 13703768323 | Why is it important to locate the point of origin quickly? | residues of accelerants that may have been used evaporate fast | 62 | |
| 13703780874 | When the origin of the fire has been determined | a detailed diagram of the site is drawn. it includes windows, wall, floors, ceiling composition, exits, types of locks, etc | 63 | |
| 13703807143 | why do investigators call in experts to examine and inspect items? | determine if they could have accidentally started the fire. | 64 | |
| 13703822342 | if an arsonist starts a fire in a multi-storey building, where do they normally start it? why? what does this mean to investigators? | first floor to escape quickly. investigators will have to move much debris to find evidence | 65 | |
| 13703844674 | What will an arsonist do to ensure the whole building burns? | multiple points of origin | 66 | |
| 13703849867 | What are the three important burn patterns? | classic V, doughnut pattern, ignitable liquid pour | 67 | |
| 13703857917 | classic V pattern | fires tend to move upwards. when it moves upwards on a verticle surface, a v pattern is created. the point of origin is at the bottom of the v, therefore, investigators will look for accelerants at the bottom | 68 | |
| 13703877314 | the doughnut pattern | when a liquid accelerant is poured on carpet and lit, it typically makes a circular doughnut pattern evidence of the accelerant is found inside the doughnut because the melted carpet material in the doughnut interior protects the carpet padding, which is saturated with fuel, from the effects of the fire | 69 | |
| 13703932895 | the ignitable liquid pour | intense burn patterns caused by accelerants directly where they were poured low points in nonporous surfaces will burn longer causing darker burn patterns when it is poured onto porous surfaces like wood, it can seep through the material under the floor and create a pattern of burn and unburned places where the fuel drips (rundown burn pattern) hydrocarbons tend to do physical damage whereas other accelerants like alcohol cause less physical damage and more superficial scorching | 70 | |
| 13703984046 | Nonporous surfaces | surfaces that do not allow absorption | 71 | |
| 13703990186 | porous surfaces | Surfaces that have tiny openings which allow liquid to be absorbed or to pass through. | 72 | |
| 13703996945 | rundown burn pattern | caused by a porous surface patterns of unburned and burned places where fuel drips | 73 | |
| 13704414312 | Once investigators take the evidence from the crime scene, | it is analyzed and interpreted by forensic lab specialists. these people determine the cause of the fire. the most common service these experts can provide is to analyze fire debris for suspected accelerants | 74 | |
| 13704443857 | if arsonists use an excess of accelerant to start a fire, | accelerant reside will remain and may be detected once the fire is out | 75 | |
| 13704449478 | if a small amount of accelerant is used | there may not be any residue left in the debris | 76 | |
| 13704458641 | to ensure evidence is not contaminated | proper collection and storage of fire evidence is crucial | 77 | |
| 13704475218 | evidence that is suspected to suggest that an accelerant was used can be stored in | for tight containers to prevent the accelerant from evaporating | 78 | |
| 13704480317 | control evidence | taking the same piece of material from another place at the scene to verify the properties of the material. it determines if an accelerate was or was not placed there. this is important if they find a flammable cleaning material from general maintenance of the carpet the analysis of a piece of control evidence show that when burned, it produced hydrocarbons as it breaks downs, which can be mistaken for accelerants | 79 | |
| 13704522544 | if a piece of evidence from the suspect point of origin is taken, | the same type of material from a different area of the scene must be taken so they can be compared | 80 | |
| 13704551965 | two methods for finding and collecting physical evidence: | 1. accelerant detection dogs 2. photo ionization detectors (PID) | 81 | |
| 13704565590 | Accelerant detection dogs | some dogs are able to sniff and detect any type of accelerant that may have been used to start a fire when they find an accelerant, they will sit and/or bark to get their handlers attention often where the dog finds the accelerant is also the point of origin | 82 | |
| 13704588301 | Photo Ionization Detector | hydrocarbons can be detected using a PID. it is a sensitive portable device that detects hydrogen vapours. it narrows the search for hydrocarbon residue so that evidence around these areas can be collected and analyzed further. the PID contains an ultraviolet lamp that emits energy packets that makeup light called photons. when the photons hit hydrocarbon molecules, they get absorbed. in the process the molecules will break apart and emit an electron due to the increase in energy, creating ions. these ions flow into the PID and interact with it by covering their energy into a digital reading. This happens very quickly. | 83 | |
| 13704646057 | drawbacks of PID's | cannot detect the type of hydrocarbons may give false readings due to humid conditions | 84 | |
| 13704744927 | Two ways to indicate in a lab that an accelerant was used? | Headspace technique vapour concentration | 85 | |
| 13704758513 | Headspace Technique | Material with accelerant placed in air tight container Heat container to allow accelerants to evaporate more easily Vapors pulled out of the top of container using a syringe the size of the syringe will limit the volume of vapour removed | 86 | |
| 13704786294 | Vapour concentration | material with accelerant placed in air tight container with an absorbent substance heat container to 60 degrees for one hour. this will ensure sufficient amount of vapour is expelled from the debris the absorbent substance absorbs any accelerant vapour in the container the charcoal strip is washed with a carbon disulphide solution this method is preferred because a greater concentration of accelerant is recovered, making the sample ore sensitive to tests | 87 | |
| 13704853327 | Metal Oxide Sensor | once vapour concentration is done, you can use this process. it is inexpensive and has been around for a long time the fumes from the samples are exposed to metal oxide sensors, which will change how the metals in the detectors react to electricity the downside is that they can react to moisture or carbon dioxide, which results in false measurements | 88 | |
| 13705678973 | explosives contain | one or more chemical compound that, when detonated, decomposes or react very rapidly. in this process, energy in the form of heat, light, sound, and destructive shock waves are produced | 89 | |
| 13705712464 | why are explosives often placed inside of a container? what type of container is it made out of? | build pressure inside to increase once the chemical reactions being a metal casing | 90 | |
| 13705721531 | Shrapnel | fragments of an exploding shell or bomb. they can cause extended damage to people, buildings, vehicles, or anything near the explosive blast | 91 | |
| 13705749434 | How are explosives used by criminals different from the ones used by the military? | military: mass produced, standard designs and components, deployed in standard ways Criminals: custom made using a variety of explosives which have varying levels of power and chemical stability uses vary and are often used in criminal activity | 92 | |
| 13705770342 | improvised explosive devices | IED - a civilian bomb (homemade) | 93 | |
| 13713016692 | an explosive device has an ______ ______ or a _____ that when ignited causes a chemical reaction between the compounds in the metal casing | ignition source , fuse | 94 | |
| 13713024563 | a fuse is | cord made of combustible material. its length will determine the burn time before the explosive is set off | 95 | |
| 13713084460 | What are ways a bomb can be detonated? | fuse mechanical timer electronic timer chemical timer impact (throwing, dropping) remote (wire or radio waves) time delay switch ignition switch starting vehicle (car bomb) | 96 | |
| 13713134381 | what is the most planned detail in a bomb? why? | ignition source. it makes or breaks a bomb | 97 | |
| 13713160635 | within the casing of an explosives is either a | pure compound or an oxidizer and a fuel | 98 | |
| 13713187912 | what type of compound is nitroglycerin? what happens when it is mixed with sawdust? what is this used for? | it is a pure compound. it is highly unstable, heavy, and colourless liquid. you get dynamite (this is used for professionally controlled blasting sites) | 99 | |
| 13713233155 | oxidizer | a molecule that releases some atoms as of oxygen | 100 | |
| 13713251318 | what does an oxidizer provide in a combustion reaction? | provides one of the requirements for combustion. if combustion is already happening, the fuel source can continue burning | 101 | |
| 13713282690 | the fuel source of an explosive is | an unstable chemical compound that will produce an explosion when ignited | 102 | |
| 13713311868 | what happens when a fuel source is mixed with an oxidizer? | an explosion is created | 103 | |
| 13713328412 | what are two examples of fuel sources? what are the elements and compounds that they are made of? | black powder - charcoal, sulfur, potassium nitrate flash powder - aluminum or magnesium plus potassium nitrate | 104 | |
| 13713366841 | similarities between fire and explosions? | must be ignited need a fuel need oxygen physical damage could be used to destroy evidence | 105 | |
| 13713378707 | differences between fire and explosions? | a fire must be started with heat. explosions can be started with electricity, radio waves, friction, etc. fires do not explode explosions happen relatively quickly, fires are slow explosions have shrapnel, fires have falling debris, etc. explosions have shockwaves | 106 | |
| 13713932446 | to be considered an explosive a substance | must react rapidly when exposed to heat or shock and must produce gas and energy rapidly | 107 | |
| 13713950646 | an explosion | the oxidation and combustion of at least two unstable substances that produce a violent reaction | 108 | |
| 13713966460 | what are the two general types of explosives? how are they categorized? | low explosives and high explosives. how quickly the explosive compound ignites and how fast the chemical reaction occurs | 109 | |
| 13714047344 | low explosives | sensitive to heat, friction, and temperature. around 2300m/s (7x faster than the speed of sound) only lethal when confined to a sealed container in which huge pressure occurs often created with easy-to-find materials like fertilizer, gunpowder, or gasoline often used by criminals ex. car bomb, pipe bomb | 110 | |
| 13714087313 | high explosives | larger, more complex, more powerful than look explosives around 6900m/s (21x faster than the speed of sound) the buildup of pressure and gas within the explosive is almost instantaneous. less sensitive to heat, friction, and temperature ex. nitroglycerin, TNT, military warheads | 111 | |
| 13714121785 | what are the most commonly used methods to locate explosive devices? | bomb detection dogs, bomb detection robots, x-ray machines, and metal detectors | 112 | |
| 13714160401 | after a bomb has been located, whether it is detonated or not, investigators must identify the type of ... why? | chemical compounds that could have caused the explosion. this can help identify the suspects and/or help to prove which suspect committed the crime | 113 | |
| 13714212177 | the two most common methods used to identify explosive compounds involve complex processes called | gas chromatography and mass spectrometry. this process involves looking at light patterns produced by excited particles within the explosive | 114 | |
| 13714234906 | bomb detection dogs | rarely malfunction cannot identify the type of explosive can detect hundreds of different explosives after it locates an explosive, it is safely and carefully removed | 115 | |
| 13714261525 | bomb detection robots | very safe very expensive a robotic device used to locate and safely remove explosive devices. it is used when a bomb threat has been issued or a suspicious package has been detected. the area the bomb is near is cleared to prevent any harm to humans. the robot is linked to several cameras. they also operate an extendable arm to disarm, remove, and/or detonate a comb safely | 116 | |
| 13714354536 | X-ray machines | determines the densities of the substances within an explosive. investigators know the densities of the possible substances that could be in an explosive, they can compare them to what the x-ray machine finds. it is up to the operator of the machine to determine if the material is explosive or not used in police departments, airports, highly secure government facilities | 117 | |
| 13714413706 | metal detectors | since most explosives are contained in a metal casing a metal detector could be used to find suspicious objects that could be an explosive this only detects metal, the nature of the explosive can only be found by other means inexpensive but often detects more distractions than explosives used in police departments, airports, highly secure government facilities | 118 | |
| 13714483196 | EGIS - Erieye Ground Interface Segment | a military software package that uses gas chromatography and mass spectrometry to detect the presence of plastic, commercial, or military explosives a sample residue is collected by rubbing a special wipe on an object or person. the sample is heated until it becomes gaseous. the gas is analyzed to see if it contains any nitro-groups (many high explosives contain nitrogen) this process takes a very long time | 119 |
