1) What are some methods used by investigators to determine the strength of the bomb?

2) Why is this information important to finding the suspect of the bombing?

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Unit 4: Explosions #3 Aim: How is the strength of a bomb determined by forensic scientists? (Part 1) Bomb Blast Effects: The effects of an explosion are created through the action of several rapidly occurring events. The most damaging phase of the explosion is the initial blast wave that radiates rapidly outward from the epicenter. This wave of highly compressed air inflicts the primary damage to structures and people. The initial blast wave, also called shock waves, violently expel fragments of the casing and shrapnel such as nails or screws that may have been added to the device. In addition to the shrapnel from the device, when an explosion occurs in or near a building, fragments from high velocity glass shards and other building materials can be a large contributor to injuries. The blast may also produce high heat and a fireball that could start secondary fires or explosions. In most explosions the seat of the explosion should be apparent, but structural damage and physical damage to vehicles can be used to approximate the location of the seat of the explosion. Collected Evidence: A detailed investigation of a blast site will reveal crucial clues to lead the investigation. By thoroughly documenting the condition of the scene, including any structural damage and injuries or fatalities, investigators can slowly piece together what occurred. Fragments of an exploded device will often be left intact, including switches, wiring, timers and circuit boards. If the timer was made from a unique type of watch, for instance, that information could help narrow the search for who created the device or where it may have come from. After an explosion, residue from the explosive that was used will be left behind. To identify the type of explosive used, investigators may use an ion mobility spectrometer (IMS), a handheld chemical detection device, to identify residues that may be present around the blast site. For large scale incidents, the area of investigation may be expansive. The bombing of the Pan Am Flight 103 over Lockerbie, Scotland in 1988 created the largest crime scene in the world. It stretched for more than 1,200 square miles. By painstakingly piecing together the wreckage that was found in this area, investigators identified trace amounts of explosives that helped confirm the incident was indeed caused by a terrorist attack. Two hundred seventy people died that day - 259 on the plane and 11 residents of Lockerbie. In addition to collecting physical evidence, video footage may be available om security cameras or from witnesses' cell phones. Investigators will also interview witnesse victims to gather crucial details. Strength of the Bomb: A bomb blast killed at least 23 people in the baggage claim area of Moscow's Domodedovo airport on Monday afternoon. Within 100 minutes of the explosion, authorities had determined that the bomb's strength was equivalent to seven kilograms of TNT. How did they figure that out so fast? By checking the walls, probably. Forensic investigators can estimate a bomb's strength by examining its effects on nearby walls, windows, cars, and human victims. For example, a seven-kilogram TNT bomb detonated in a relatively open space might crack a brick wall 45 feet away. The explosion would damage plaster walls and asbestos shingles at around 115 feet. Single-strength window glass would shatter at a distance of 210 feet. Human eardrums could be damaged within 40 feet, and there's a chance that anyone within 12 feet would die. These estimates, however, are extremely rough. In an enclosed area like an airport, the pressure waves bounce off of the ceiling and walls, increasing the bomb's destructive force. And injuries will vary depending on how a person is oriented in relation to the blast. Unit 4: Explosions #3 Aim: How is the strength of a bomb determined by forensic scientists? (Part 1) Bomb Blast Effects: The effects of an explosion are created through the action of several rapidly occurring events. The most damaging phase of the explosion is the initial blast wave that radiates rapidly outward from the epicenter. This wave of highly compressed air inflicts the primary damage to structures and people. The initial blast wave, also called shock waves, violently expel fragments of the casing and shrapnel such as nails or screws that may have been added to the device. In addition to the shrapnel from the device, when an explosion occurs in or near a building, fragments from high velocity glass shards and other building materials can be a large contributor to injuries. The blast may also produce high heat and a fireball that could start secondary fires or explosions. In most explosions the seat of the explosion should be apparent, but structural damage and physical damage to vehicles can be used to approximate the location of the seat of the explosion. Collected Evidence: A detailed investigation of a blast site will reveal crucial clues to lead the investigation. By thoroughly documenting the condition of the scene, including any structural damage and injuries or fatalities, investigators can slowly piece together what occurred. Fragments of an exploded device will often be left intact, including switches, wiring, timers and circuit boards. If the timer was made from a unique type of watch, for instance, that information could help narrow the search for who created the device or where it may have come from. After an explosion, residue from the explosive that was used will be left behind. To identify the type of explosive used, investigators may use an ion mobility spectrometer (IMS), a handheld chemical detection device, to identify residues that may be present around the blast site. For large scale incidents, the area of investigation may be expansive. The bombing of the Pan Am Flight 103 over Lockerbie, Scotland in 1988 created the largest crime scene in the world. It stretched for more than 1,200 square miles. By painstakingly piecing together the wreckage that was found in this area, investigators identified trace amounts of explosives that helped confirm the incident was indeed caused by a terrorist attack. Two hundred seventy people died that day - 259 on the plane and 11 residents of Lockerbie. In addition to collecting physical evidence, video footage may be available om security cameras or from witnesses' cell phones. Investigators will also interview witnesse victims to gather crucial details. Strength of the Bomb: A bomb blast killed at least 23 people in the baggage claim area of Moscow's Domodedovo airport on Monday afternoon. Within 100 minutes of the explosion, authorities had determined that the bomb's strength was equivalent to seven kilograms of TNT. How did they figure that out so fast? By checking the walls, probably. Forensic investigators can estimate a bomb's strength by examining its effects on nearby walls, windows, cars, and human victims. For example, a seven-kilogram TNT bomb detonated in a relatively open space might crack a brick wall 45 feet away. The explosion would damage plaster walls and asbestos shingles at around 115 feet. Single-strength window glass would shatter at a distance of 210 feet. Human eardrums could be damaged within 40 feet, and there's a chance that anyone within 12 feet would die. These estimates, however, are extremely rough. In an enclosed area like an airport, the pressure waves bounce off of the ceiling and walls, increasing the bomb's destructive force. And injuries will vary depending on how a person is oriented in relation to the blast.

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Solution1 Some methods to investigate the bombs are To identify the type of explosive used Method 1 ... View the full answer