The document describes a case scenario involving injuries from a blast. At the crime scene, police found bodies that were grossly mutilated, burnt, and missing limbs. One victim, Mr. A, was found alive but unconscious with an amputated arm and multiple small wounds. Another, Mr. D, was admitted with severe breathing problems, wounds all over his body, and crushed legs, later dying in the hospital. The document goes on to define explosion and blast injuries, describing the mechanisms of primary, secondary, tertiary, and quaternary injuries caused by the blast wave, flying debris, and effects of fires or building collapses. Causes of death from blast injuries include blunt trauma, burns, as

1. BLAST
INJURIES

3. .
CASE SCENARIO
During the procession of a political party, a sudden explosion
occurred and immense chaos was created. Police arrived at the crime
scene and found:
A grossly mutilated burnt body at a particular site. Forensic
DNA sampling revealed it’s chopped off head that was recovered
from about 200 yards.
Some bodies besides it, were found disintegrated, others were
mutilated and burnt, with massively torn clothes. Limbs were
amputated. Metal pieces and nails were also seen embedded in
their bodies
Mr. A was found alive but unconscious, his upper limb was
amputated and clothes were torn and burnt. He had multiple
bluish and superficially bleeding wounds of 2-10 mm,,
confluent at various sites. Many punctate, irregular wounds of
around 3cm, could also be seen. Dirt tattooing could also be
appreciated

4. .
CASE SCENARIO
Mr. B had similar injuries but few and bigger than
Mr. A and without dirt stippling.
Mr. C had no obvious injuries but developed headache
,irritability and nausea. Also he had difficulty in breathing
and blood stained sputum . He was complaining loss of
hearing and tinnitus too
Mr. D who was sitting close to a broken wall, was
admitted in emergency, with severe dyspnea and
multiple wounds randomly all over the body and a well
demarcated cyanosis of face upto upper chest. His
lower limb also crushed. He died 2 days later.

6. Learning Objectives:
Students will be able to :
 Define explosion and mention different
types of explosives
 State the mechanism of blast wave and its
types
 Define blast injury, briefly explain its
types , factors responsible for it along
with its medico-legal aspects and
mention causes of death in such injuries

7. DEFINITION:-
It is a complex type of physical trauma resulting
from direct or indirect exposure to an explosion.
EXPLOSIVE /BLAST INJURY

8. EXPLOSION:
An explosion is a rapid expansion in volume
associated with an extremely vigorous outward
release of energy, which is then dissipated by a blast
wave, by translocation of objects in space, or by
generation of heat.
TYPES
• Natural
• Chemical
• Nuclear
• Electrical
• Magnetic
• Domestic
• Mechanical
In case of Medico-legal practice, the most common
are chemical whereas less common are mechanical
Terrorist bombings some times involves dual
explosions.

9. Explosives
 This refers to substances which have a
shattering or brisant effect when they explode.

10. A. By velocity
propagation
1. High order explosives
2. Low order explosives
CLASSIFICATION OF EXPLOSIVES:-
Fire work

11.  High order explosives rises the pressure
up to 2,75,000 atm. A high order
explosive functions by detonation.
 Low order explosives burns in a matter
of milliseconds & generates a pressure of
about 6000 atm. A low order explosive
functions by deflagration.

12. Other Explosives:
Letter bomb
Molotov Cocktail
Booby trap

13. Dynamite
 This term comprises various explosives consisting
of
 nitroglycerol,
 ammonium nitrate,
 saltpetre,
 aromatic nitro compounds.
 Shattering power of dynamite is reduced by adding
common salt.

14. (TATP) -Triacetone-Triperoxide-
Dynamite; Its
Detonating device has :
Blasting cap with
ignition powder(primer)
Triggered by:
impact
Electric ,(slow burning
safety)
Fuse , time fuse
Research Department Explosive"
(R.D.X.)
Nitroamine

16. Mechanism of Injuries from
Explosion
 These are mainly due to four factors
 BLAST EFFECT
 FLAME OR HOT GASES.
 FLYING MISSILES.
 ANOXIA.

17. BY FOUR FACTORS:
 Blast(shock wave)
 Can shatter or blow the victim
 Damage hollow and fragile organs
 Easily transmitted in water(800 t denser )
 Here it cause more severe damage to hollow
organs and viscera
 Flame or hot gases
 Cause blackening(soot) and tattooing(burnt and
unburnt particles driven in skin)
 Flying missiles(explosive debris , primary
secondary)
 Area of contact most effected
 Anoxia and Histotoxic anoxia
 CO, nitrous and nitric
gases,H2S,SO2,hydrocyanic acid
MECHANISM OF EXPLOSIVE INJURIES:

18. MECHANISM:
 Hot expanding gases pressure wave
 It spreads concentrically
 Speed is 21000km/hr
 Pressure rises by 2,75000 atm.
 Flows around barriers and reflects
BLAST WAVE:

19.  Injuries are mainly due to initial shock
wave, but they are aggravated based on
phases.
 Intensity of an explosion declines as
the cube root of distance from an
explosion.
High pressure area
Low pressure area
(Pressure in region of explosion-Normal AP)
Partial vacuum

20. 1. Air blast
2. Immersion blasts
3. Solid blast
Components of blast waves:
 Shock wave(destruction to hollow organs
and viscera)
 Blast wind(amputation ,disruption)
TYPES OF BLASTS:

21. 1. Primary blast injuries
2. Secondary blast injuries
3. Tertiary blast injuries
4. Miscellaneous/Quaternary blast injuries
Primary blast injuries:
 Caused by direct effect of pressure wave.
 Injuries are due to compressed air which
tends to effect the air filled organs like
lungs
CLASSIFICATION OF EXPLOSIVE INJURIES:

22. Secondary blast injuries:(primary and
secondary missiles)
Are due to flying objects generated by the
actual blast.
Tertiary blast injuries:
Occurs when victims are thrown into air &
strike to other objects
Miscellaneous/ Quaternary injuries:
Injuries due to fire or collapse of
buildings. Causes respiratory injuries,
traumatic asphyxia & crush injuries.

23. BLAST INJURIES TYPES

24. BLAST INJURIES TYPES

25. Injury pattern
according to distance:
In immediate contact:
the victims body would be
blown into pieces & some
parts of the body may be
scattered over wide areas.

26. When at a little distance
away from the explosion
With in 1 meter. Torso
badly damaged,
amputation,torn clothes
Beyond 1 meter: Injured
clothes torn,may have
amputation

27. With in few meters:(2-4)
Clothes torn,
limbs amputated,
Marshall’s triad of bruise,
abrasion(2-1omm) and punctate
laceration(3cm) with dirt
tattooing
May coalesce to give bigger lesion
Beyond few meters:
Tattooing disappears
Large fragments impacted in body
cavities

28. CAUSE OF DEATH
 Body may be completely shattered and
disintegrated as a result of blast effect in the
vicinity of the blast.
 Blunt force, injuries, falling debris or from burns.
 Asphyxia, due to inhalation of products of
combustion (CO, H,S, SO, HCN, nitrous and
nitric gases).
 CRUSH SYNDROME, crushed by debris of
building demolished by explosions.

29. It is the most common fatal
primary blast injury.
It includes conditions like:
 Pulmonary contusion
 Systemic air embolism
 Free radical associated
injuries(thrombosis, DIC)
CAUSES OF DEATH
Blast Lung/ Pulmonary Barotrauma:
Butterfly pattern of fluffy infiltrate

30.  ARDS may be the result of direct lung
injury during explosion / shock from other
organ system damage.
 Traumatic asphyxia, falling debris
 hemorrhage
 Burns Crush syndrome
 Anoxia due to inhalation of combustion
products
 Delayed causes like septicemia

31.  Loss of consciousness.
 Increase drowsiness.
 Pupils slow to
react/unequal.
 Blurred vision.
 Bleeding or CSF leakage
from the nose/ears.
 Slurred speech.
 Vomiting.
2. Signs Of Head Injury:

32.  Most sensitive to blast.
 Rupture of tympanic
membrane.
 Damage to cochlea and
eustachian tube.
 Deafness (sensorinueural
or conductive or both).
 Ossicular chain gets
affected
 Tinnitus.
3. Damage to ear due to air blast:

34. Post Mortem Appearance
 Small foci of brain haemorrhages
 Pulmonary haemorrhages
 Haemorrhages in bowel and mesentry
 Passive hyperaemia and edema cause
secondary lesions
 Contusion of brain, heart
 Ruptured organs like stomach bowel

35.  Accidental:
Domestic LPG/pressure cookers
 Suicidal :
In case of suicidal bombers
 Homicidal:
Terrorist activities, passenger aircraft
explosions.
Home made(sodium sugar chlorate)
Parcel bombs/letter bombs
Time bombs
Impact bombs(TATP)
Incendiary bombs(Molotiv cocktail)
MEDICO LEGAL IMPORTANCE:

36. IDENTIFICATION OF DEAD:
Assumes greater importance in mass
disasters
 Radiological examination:
It is also important in evaluating cause
of death.

37.  Blood tests:
For CO, nitrous and nitric
gases,H2S,SO2,hydrocyanic acid
 Histopathology:
It may help to detect ARDS,
pulmonary contusion or renal failure
resulting from crush syndrome.
 Explosive residues: They are to be
collected for subsequent examination by
expert in field of explosives.

38. THANK YOU