SABT 6 C Intro to Explosives Flashcards
2 ID 3 types of explosions.
-1 Mechanical Explosion
2 Chemical explossion
3 Nuclear Explosion
1 Define terms associated with the fundamental of explosives.
-Chemical explosives 1 low explosive 2 high explosive 3 Explosive Work or power 4 Brisance 5 Explosive train 6 Initiation 7 Explosion 8 Combustion 9 Deflagration 10 Detonation 11 Detonation velocity 12 Low order detonation 13 High order detonation 14 Sympathetic detonation
3 ID THE effects of an explosion.
-Positive blast pressure
1 positive pressure
2 Overpressure
3 Blast overpressure
Negative blast pressure
1 refection
2 shielding
3 venting
4 ID the categories, characteristics and safety precautions for explosives products.
-Low Explosive ie black powder, smokeless powder
Flash powder
- High Explosive
- Secondary High explosive
5 ID basic precursors used to make homemade explosives
-TATP -white crystalline powder, instability, unsuitable for commercial or military use
Made of acetone, peroxide, sulfuric acid
-HMTD -composed of hexamine, peroxide, and citric acid
6 ID elements of an explosive train.
- ordered combination of explosive necessary to achieve an explosion.
- fundamental in all chemical explosions
- may be initiated either electronically or non electronically
- some high explosives cannot be detonated unless a booster is added to the explosive train.
1 non electrical initiation -time fuse -Non electrical detonator 2 shock tube firing system (NOEL) -electrical STSTEM
What explosive that characterized by deflagration or low rate of reaction and the development of low pressure. This explosive undergo a relatively show chemical reaction and created a subsonic explosion (below 3,300 fps, below speed of sound). No shock wave is generated and the reaction is propagated by very rapid burning.____ explosive are typically classified as pyrotechnics and propellants.
-What kind of power does it have
Low Explosive (LE) -Pushing or heavy power.
Explosive that are characterized by a very high rate of reaction, high pressure development and the presence of a detonation wave in the explosive. During the process of detonation, the high explosive is decomposed into hot, rapidly expanding gas resulting in a supersonic explosion over (3300 fps). _____ explosive are chemical that can detonate.
-have the ability to _____or ____depending upon the _______
High Explosive (HE)
-push or shatter,
detonation velocity of the material
___ is directly related to the functioning velocity of an explosive.
-BC specific velocities are required to perform specific tasks, explosive manufactures may combine several explosive substance to achieve a particular velocity of detonation.
Explosive Work or Explosive Power
are unstable substances or mixtures of substance capable of undergoing sudden and violent decomposition or break-up. When they do they produce a explosion through great quantities of heat, energy and gas which are generated and released at very high speeds. ___ explosive include molecular explosive like TNT and nitroglycerin or composite explosive like ANFO and Dynamite
Chemical Explosives
Shattering or crushing effect of a sudden release of energy from an explosive, destructive fragmentation effect of an explosive charge on its immediate vicinity ability of explosives when detonated to shatter, rip or tear its surrounding (high detonation velocity)
Brisance
Ordered combination of explosive necessary to achieve an explosion
-initiation is the first step in the explosive —–
1. Fundamental process in all chemical reactions
2. may be initiated either electrically or non electrically
3 some high explosives cannot be detonated unless a booster is added to the ________
Explosive Train
This the first step in an explosive process
-it starts the reaction that leads to the explosion
Initiation
Dynamite is what type of explosive
High Explosive very fast
What is the sudden and violent escape of gases from a central point accompanied by high temperature, violent shock, and loud noise. Involve either a detonation or a rapid deflagration
Explosion
may be divided into 3 broad categories =: slow, rapid and instantaneous
Combustion
What is nothing more than normal burning, the heating of a substance as it reaches its ignition point.
Slow Combustion
What is referred to as explosion, if confined. In a internal combustion engine, the flame from a spark plug ignites the mixture of gasoline and air, resulting in an explosion
Rapid Combustion
this is called detonation. It is the ______ of the explosive substance from a solid or liquid to a gas. It creates ___
Instantaneous combustion
shock wave
Altho detonation is referred to as _____, there is an interval of time required for the explosive to be consumed.
Instantaneous Combustion
what is very rapid exothermic (burning), self propagating chemical reaction through un-reacted material at a velocity less than the speed of sound (below 3300)
Deflagration
_________ A chemical reaction given by an explosive substance which PRODUCE a _____ High temperature and pressure gradients are generated in the wave front so that the chemical reaction is initiated instantaneously.
- Detonation
- Shock wave
Speed at which the Shock wave passes through a column of explosives.
-range of 3300 to 30,000 fts
Detonation velocity
A. what is Either the incomplete consumption of the explosive or complete consumption, but at lower than optimum velocity
B. Cause of a low order detonation may include deterioration of explosive, poor contact between the initiator and the explosive, disruption of the shock wave due to air bubbles or impurities in the explosive, incompatible explosive, insufficient powers in the initiator, or a combination of any of these factors
Low order detonation
the complete consumption of the explosive at its optimum (highest) velocity.
High order detonation
the initiation of an explosive from the shock wave of another explosive charge in close proximity.
sympathetic detonation
What are the 3 types of explosions
Mechanical
Chemical
Nuclear
- What explosion involve the conversion of a substance such as water to gas in the form of steam. IE would be a water heater that overheats wo a pressure release valve, the result would be an explosion from build up of stem
- It does not involve the conversion of a substance to a different chemical composition, as with a chemical explosion.
Mechanical Explosion
-(strictly mechanical pressure without any explosive chemical reactions
1 This involves the rapid conversion of a substance, solid or liquid, into a gas. These material relatively small in bulk, are transformed into a large volume of hot gases in a fraction of a second
2 Generation of high pressure gas is the result of exothermic reaction here the chemical nature of the fuel is changed; expanding gases produces a shock wave
3 __ explosive contain their own fuels and oxidizers in the compound to propagate a constant velocity thru the explosive charge
4 oxidizers: potassiums chlorate, ammonium nitrate, sodium nitrate, hydrogen peroxide, sodium hydroxide
5 fuels : aluminum, magnesium, nitromethane, fuel oils and liquids hydrocarbons
Chemical Explosion
What contain their own fuels and oxidizers in the compounds to propagate a constant velocity through the explosive charge
Chemical explosive
Potassium chlorate, ammonium nitrate, sodium nitrate, hydrogen peroxide, sodium hydroxide are what
Oxidizers
These are examples of what Aluminum magnesium nitromethane fuel oil and liquid hydrocarbons
Fuels
What explosion produce the most damage
1 fission, or the splitting of the nucleus of atom
2 Fusion, the joining together under great force of the nuclei of atom
3 Tremendous release of energy, heat gas, shock
4 Produces radiological alpha, gamma and beta fallout.
Nuclear Explosion
What are the two phases of blast pressure
1 Positive Blast Pressure
2 Negative Blast pressure
A. This is one of the initial blast effects of an explosion
B. is more powerful than the negative phase and is responsible for the majority of blast pressure damage.
Positive Blast Pressure
Occurs as the hot, expanding gases create a pressure wave that radiates outward from the explosion at high speed and with great force.
Positive pressure
______ is positive pressure, which will cause the body to sustain physical damage. Damage from this pressure will reduce with distant from blast
Overpressure
A. Pressure exceeding the ambient pressure manifested in the shock wave of an explosion (expressed in psi
B. Overpressure is the sharp instantaneous rise in atmospheric pressure resulting from an explosive detonation, which is greatly reduced with distance from blast
Blast Overpressure
The three types of pressure that belongs to Positive Blast Pressure
- Positive Pressure
- Overpressure
- Blast Overpressure
A. As positive blast pressure phase of the explosive moves outward from the origin of the explosive, it displaces, compresses, and heats the surrounding air creating a low air pressure condition behind the wave front.
B. When positive pressure phase dissipates, air rushes back to the area of origin to equalize the surrounding air pressure. Last 3 time longer than positive phase
C. Air rushing back towards the area of origin is called the negative pressure phase. This phase can cause 2ndary damage & can move items of physical evidence towards the blast seat. This phase is considerably less powerful than positive pressure phase but may be of sufficient strength to cause additional damage to property
Negatively Blast Pressure.
Name the 3 Blast Mitigation Methods
1 Reflection
2 Shielding
3 Venting
Occurs when the blast pressure wave strikes an immovable object in its path
Shielding