FLETC Written Exam 4 With Verified
Answers Latest Updated 2024/2025
Graded A+ | FLETC Exam Questions
With Answers & FLETC Written Exam
1 With 100% Correct Answers
2024/2025 | (Graded A+)
Three Types of Explosions - ANSWER-Mechanical
Chemical
Nuclear
High Explosive - ANSWER-Explosive which normally requires a blasting cap for
initiation and once initiated produces a supersonic detonation with a shattering or
brisant effect
Detonate without confinement, doesn't need container
Low Explosive - ANSWER-Explosive, which when unconfined, responds to
initiation by deflagration or burning and produces a pushing effect
Transitions from deflagration to detonation when confined
Incendiary Explosive - ANSWER-Explosive designed to start fires or destroy
sensitive equipment
Detonation - ANSWER-Supersonic combustion that propagates through shock
compression generating exothermic heat and an accompanying blast wave
Deflagration - ANSWER-A subsonic combustion that propagates through thermal
conductivity
Effects of an Explosion - ANSWER-Thermal
Blast Pressure
Fragmentation
Thermal Effect - ANSWER-Usually seen as a bright flash or fireball at the
moment of detonation
,May cause localized ignition of highly combustible materials
Generally least damaging of the three effects
Blast Pressure Effect - ANSWER-Very hot gasses (between 3,000 and 7,000
degrees Fahrenheit) expand out from the point of detonation at supersonic
velocities (up to 20,000 mph)
The further the pressure wave travels, the less power it has
Most powerful and destructive/deadly of the effects
When taking place in a confined area, it can amplify the original blast wave
Two Phases of Blast Pressure - ANSWER-Positive Phase
Negative Phase
Positive Phase of Blast Pressure - ANSWER-Pressure wave moving outward
from the point of detonation
Negative Phase of Blast Pressure - ANSWER-Partial vacuum is created near the
epicenter due to the outward movement of air and the consumption of oxygen
from the combustion process
4 Types of Injuries Sustained During a Blast - ANSWER-Primary Blast Injury
Secondary Blast Injury
Tertiary Blast Injury
Quaternary Injury
Primary Blast Injury - ANSWER-Caused by direct effects of blast
Secondary Blast Injury - ANSWER-Caused by propelled fragmentation (most
deadly)
Tertiary Blast Injury - ANSWER-Occurs when a casualty's body is propelled by
the blast against the ground or stationary objects
Quaternary Injury - ANSWER-Any other injuries (burns and crush injuries)
Three Mechanisms of Primary Blast Injury - ANSWER-Implosion
Spalling
Inertial Effects
, Implosion - ANSWER-Occurs when blast impacts the human body by
compressing air-filled cavities in the body and causes tissue damage as
compressed air stretches, tears, and ruptures internal organs and tissues
Spalling - ANSWER-Describes tissue injury caused when blast wave rapidly
changes velocity as it moves through tissues of different densities
Blast Lung - ANSWER-Severe form of pulmonary contusion, crushed lung tissue
fills with blood and cannot exhange oxygen
Inertial Effects - ANSWER-Injury occurring when connected tissues of different
densities move at different velocities
Progressive Collapse - ANSWER-Refers to the spread of an initial local failure
from element to element, eventually resulting in a disproportionate extent of
collapse relative to the area of initial blast damage
Two Types of Progressive Collapse - ANSWER-Pancaking
Cascading
Pancaking - ANSWER-Occurs when an explosion destroys a structural member
or members, causing floor directly above destroyed members to collapse and the
floor above that to collapse and so on
Cascading - ANSWER-Collapsing of a series of bays from the destruction of one
or few bays
Fragmentation Effect - ANSWER-When an encased explosive such as a pipe
bomb detonates, the rapidly expanding gases produced by the explosion enlarge
the casing to about one and one-half times its original diameter before it ruptures
When it ruptures, the casing breaks into fragments that are propelled away from
the center of detonation
Primary Fragmentation - ANSWER-Has intimate contact with explosive material
or is produced by the explosive container/device
Yields incriminating forensic evidence
Secondary Fragmentation - ANSWER-Objects propelled from around detonation
point, and fractured pieces of the intended target that become lethal missiles
Firebrand - ANSWER-Projected hot fragmentation, burning energetic material, or
burning debris whose thermal energy is transferred to the surroundings
Answers Latest Updated 2024/2025
Graded A+ | FLETC Exam Questions
With Answers & FLETC Written Exam
1 With 100% Correct Answers
2024/2025 | (Graded A+)
Three Types of Explosions - ANSWER-Mechanical
Chemical
Nuclear
High Explosive - ANSWER-Explosive which normally requires a blasting cap for
initiation and once initiated produces a supersonic detonation with a shattering or
brisant effect
Detonate without confinement, doesn't need container
Low Explosive - ANSWER-Explosive, which when unconfined, responds to
initiation by deflagration or burning and produces a pushing effect
Transitions from deflagration to detonation when confined
Incendiary Explosive - ANSWER-Explosive designed to start fires or destroy
sensitive equipment
Detonation - ANSWER-Supersonic combustion that propagates through shock
compression generating exothermic heat and an accompanying blast wave
Deflagration - ANSWER-A subsonic combustion that propagates through thermal
conductivity
Effects of an Explosion - ANSWER-Thermal
Blast Pressure
Fragmentation
Thermal Effect - ANSWER-Usually seen as a bright flash or fireball at the
moment of detonation
,May cause localized ignition of highly combustible materials
Generally least damaging of the three effects
Blast Pressure Effect - ANSWER-Very hot gasses (between 3,000 and 7,000
degrees Fahrenheit) expand out from the point of detonation at supersonic
velocities (up to 20,000 mph)
The further the pressure wave travels, the less power it has
Most powerful and destructive/deadly of the effects
When taking place in a confined area, it can amplify the original blast wave
Two Phases of Blast Pressure - ANSWER-Positive Phase
Negative Phase
Positive Phase of Blast Pressure - ANSWER-Pressure wave moving outward
from the point of detonation
Negative Phase of Blast Pressure - ANSWER-Partial vacuum is created near the
epicenter due to the outward movement of air and the consumption of oxygen
from the combustion process
4 Types of Injuries Sustained During a Blast - ANSWER-Primary Blast Injury
Secondary Blast Injury
Tertiary Blast Injury
Quaternary Injury
Primary Blast Injury - ANSWER-Caused by direct effects of blast
Secondary Blast Injury - ANSWER-Caused by propelled fragmentation (most
deadly)
Tertiary Blast Injury - ANSWER-Occurs when a casualty's body is propelled by
the blast against the ground or stationary objects
Quaternary Injury - ANSWER-Any other injuries (burns and crush injuries)
Three Mechanisms of Primary Blast Injury - ANSWER-Implosion
Spalling
Inertial Effects
, Implosion - ANSWER-Occurs when blast impacts the human body by
compressing air-filled cavities in the body and causes tissue damage as
compressed air stretches, tears, and ruptures internal organs and tissues
Spalling - ANSWER-Describes tissue injury caused when blast wave rapidly
changes velocity as it moves through tissues of different densities
Blast Lung - ANSWER-Severe form of pulmonary contusion, crushed lung tissue
fills with blood and cannot exhange oxygen
Inertial Effects - ANSWER-Injury occurring when connected tissues of different
densities move at different velocities
Progressive Collapse - ANSWER-Refers to the spread of an initial local failure
from element to element, eventually resulting in a disproportionate extent of
collapse relative to the area of initial blast damage
Two Types of Progressive Collapse - ANSWER-Pancaking
Cascading
Pancaking - ANSWER-Occurs when an explosion destroys a structural member
or members, causing floor directly above destroyed members to collapse and the
floor above that to collapse and so on
Cascading - ANSWER-Collapsing of a series of bays from the destruction of one
or few bays
Fragmentation Effect - ANSWER-When an encased explosive such as a pipe
bomb detonates, the rapidly expanding gases produced by the explosion enlarge
the casing to about one and one-half times its original diameter before it ruptures
When it ruptures, the casing breaks into fragments that are propelled away from
the center of detonation
Primary Fragmentation - ANSWER-Has intimate contact with explosive material
or is produced by the explosive container/device
Yields incriminating forensic evidence
Secondary Fragmentation - ANSWER-Objects propelled from around detonation
point, and fractured pieces of the intended target that become lethal missiles
Firebrand - ANSWER-Projected hot fragmentation, burning energetic material, or
burning debris whose thermal energy is transferred to the surroundings
