ARSON INVESTIGATION

1. ARSON INVESTIGATION
Dr. Suchita Rawat
Mphil, PhD

2. Unit 1: Introduction to Forensic Chemistry (co faculty) 10 hours
Arson: Definition and introduction; Chemistry of fire; Cause and origin of fire; Fire scene patterns; Recognition of type of fire; Role of a
forensic investigator; Examination of crime scene; Collection, preservation and analysis of clue materials in: arson, accidental and
vehicular fire; Analytical techniques in arson investigation: Pyrolysis Gas chromatography, Headspace Gas chromatography; Post-
flashover burning.
Definition, history, scope and branches of toxicology; Role of a forensic toxicologist; Poison: definition, dosage, classification based on
origin, mode of action, chemical nature; Mode of administration; Factors affecting the action of poisons; Antidotes: Definition and
types; Types of exhibits encountered; Collection and preservation of different specimens in fatal and survival cases: choice of
preservations, containers, labelling, sealing and storage.
Analysis of adulteration in: cement, oils, fats, cosmetics, paints, gold, silver, tobacco, tea, sugars and salts; Analysis of adulterants like
pesticides, metals and their alloys in water, cold drinks, milk and food materials
Unit 5: Introduction to Toxicology 14 hours
Unit 3: Arson Analysis 12 hours

3. https://z-lib.org/

4. ARSON
● crime of intentionally,
deliberately, and
maliciously setting fire
to buildings, wildland
areas, houses, vehicles
or other property with
the intent to cause
damage.

5. 5 Insane Serial ARSONISTS

6. What could be the motives of a arsonist?

7. Chemistry of fire
fire triangle
fire tetrahedron
solid, a
flammabl
e liquid or
gaseous
statE

8. Phases of fire
(GASES/TEMP)
Incipient/Initial Phase (Growth Stage)
Free-Burning Phase (Fully Developed Stage)
Smoldering Phase (Decay Stage)

9. Types of fire

13. fire scene patterns:
•Plume generated patterns
•Confinement patterns
•Movement patterns
•Irregular patterns
•Spalling
•Electrical damage
•Clean burn
•Intensity patterns
•Ventilation generated fire patterns

14. Plume generated
patterns
 seen in indoor fire
scenes.
 When the fire has just
started and is new, the
pattern in an adjacent
wall will assume the
shape of the flame - it
is usually an inverted
cone pattern.
 sign of a new and young
fire.

15. Columnar patterns
 As the fire tends to
grow and gets older,
the pattern takes a
columnar shape,
 roughly
perpendicular to the
flow

16. Semicircular pattern on ceiling
 Columnar patterns have a
short lifespan and quickly
reaches the top of the room
(ceiling) and forms a
semicircular pattern on the
ceiling.
 At the top of a 3-dimensional
V shape / cone shape.
 Also note that fixing the
pattern on a ceiling is more
difficult than fixing it on the
wall.

17. Confinement pattern
 confine patterns are seen when
fire has little way to escape
from an indoor scenario.
 A hot gas layer traps beneath
the ceiling when this happens.
 So there is smoking on the top
sides of the room than the
lower sides of the room.

18. Fire investigators in confinement
fire cases can easily fix which floor
the fire broke out by the
confinement patterns, roof collapse
sequence etc.

19. when the fire breaks the ceiling
as well as the top portion of the
walls.
This is called a 'horizontal
confinement pattern' because the
damage happens in the horizontal
dimension.
In this case, the pattern to watch
out for is the greying / smoking
pattern in the other side of the
wall after the wall is penetrated
through.

20. Movement pattern
 When fire moves from one room to
another, the movement is patterned
/ recorded en-route.
 most commonly seen in at or near
doorways.
 Movement patterns are useful in
tracing fire back to its origin.
 The patterns are typically diagonal
patterns upward from the doorway.
 In such cases, the movement
pattern is diagonal, but the side
where the damage is more points
toward the origin of fire.

21. Irregular pattern/ pour
 seen on floors.
 irregular shaped smoking
patterns and interestingly
resemble a liquid that has flown
across the floor.

22. In confinement fire cases, the heat which
builds up in the top of the room, radiates
back to the floor.
This radiation is high temperature heat
(This radiation is known as a phenomenon
called ‘flashover’). This burns up the floor.
Carpets, clothes etc. which can be on the
floor get burnt up and the patterns of
them burning stays on as irregular patterns.

23. There could have been objects on the floor in a regular fire scene, which may protect the floor from
burning. This can also lead to a floor which resembles irregular fire pattern, but it is actually not an
irregular pattern fire.
**It is key to always ask what was present on the floor when encountered with irregular patterns.

24. Spalling
• damages that happen on cement and
concrete surfaces due to fire.
• The changes can be either chipping or
pitting.
• The area of damage can range from few
square centimeters to few square meters.
• Heat causes differential expansion in the
cement surface, drinks up all the water in
the surface and therefore causes pitting.
• So spalling does not require intense heat
always.

25. Electrical damage
• changes in the electrical wires or
appliances. 'Arcing through char' is the
phenomenon examined for in electrical
fires.
• Arcing through char happens when
electrical short circuit starts the fire
and the wire at the point of origin has
globules of melted copper (or the wire's
material).
• This seen under and demonstrated using
the electron microscope for greater
detail.

26. Clean burn
• There are instances in fire,
when soot never gets deposited
in certain places but gets
heavily deposited on certain
areas of the scene.
• This can happen due to less
soot formation. Less soot is
formed is cases where fire is
very intense.
• This intense fire burns away
the soot that gets formed.

27. Intensity pattern
This could be dependent on presence of
air, fuel etc. This is known as intensity
patterns.
Fire causes different patterns at
different places due to its different
intensity at different places.
Figure 14: Intensity pattern in a home. The fire
originated from the kitchen on the left side of the
building, but maximum damage was seen in the
central living area of house.

28. Ventilation generated fire pattern
• seen in many indoor fire cases and
mostly misunderstood as explosions
(eg. LPG burst, electric appliance
explosion etc.).
• The fire searches for oxygen source
and gets transferred toward the
point of ventilation - it could be a
window, ventilator or the slit under
a door etc.
• There is intense fire buildup in the
area close to the ventilation.
Figure 15: Ventilation generated fire pattern using a Fire
Dynamics Simulator (FDS). Note the points A (air draft
under the door causing intense fire close to the door) and
B (Radiant heat flux on the wall opposite to the door).

29. Simulation of a Fire in a Hillside Residential Structure--San Francisco

31. Location of point of origin of fire
Multiple vs. single
Damage
V pattern
Smoke , burn and damage patterns
Smoke and fire alarm

32. Recognition of type of fire
Arson
CCTV
footage, eye
witness
reports
broken windows,
doors, presence
of tools,
disabled
intruder alarms
Incendiary devices, fuel
bottles,
fire accelerants
Trailing marks
Odor

33. Recognition of type of fire
Accidental electrical
fire
Accidental
More damage
at POO
AC’s, ceiling
fans, kitchen
appliances
Scanning
Electron
Microscopy for
observation

34. Recognition of type of fire
Outdoor Fires
ie. Wildfires
Flat,
open
surface
will move
outwards
and
upwards
spread in
a circular
pattern
sloped
surface
will most
likely
spread in
an uphill
direction

35. Recognition of type of fire
VEHICULAR
FIRE
Service
records
insurance
history
electrical
systems
in the
vehicle
witness
reports

36. Search
Documentation (Video/
e.g., aerial
photography, infrared
photography or stereo
photography)
Interview i.e. occupants, first
responders
Preliminary assessment

37. Collection, preservation and analysis of clue materials
Point of origin
Stains of ignitable
liquids
Junction where
furniture/ wall meet
floor/ stair ends

38. ARSON
EVIDENCE
Cardboard evidence
Carpets and floors: burn
pattern/portion of flooring material
Ceramic tiles (extreme heat)
Concrete (spalling pattern)
Random point collection (3-5 spots)
Liquid evidence (bottles/containers/
poured )
burnt wood, burnt glass, plastics and
fibres.

39. 6.1 Preservation Container—Preservation containers are tightly sealed, volatile-
free, and chemically inert to the sample. An example of a suitable preservation
container is a crimp-top glass vial with intact polytetrafluoroethylene (PTFE) lined
seal.
6.2 Adsorption Media—Activated charcoal strips or loose activated carbon or
equivalent.
8.4 Store preserved extracts at room temperature (approximately 22 °C) or
lower.
(Warning—Exposure to higher temperatures can result in the evaporative loss of
lower boiling compounds from a stored extract)

41. Transient
evidence
smell and vision
accelerant vapors , chemical odor,
color of flame, and the temperature
of the fire
Pattern
evidence
glass fractures,
concrete
spalling, and
the presence of
“trailers”

42. Conditional
evidence
direction of the smoke stains,
the speed of fires spread,
the amount, type, and degree
of melted material, the
condition of the electrical
system and fuse box, the
condition of the fire alarm
and/or smoke detectors, and
the location of the safe,
important documents, and
valuables
Transfer evidence
biological evidence /physical
impressions /chemical evidence

43. Chemical Evidence at the Fire Scene
(accelerants)
Gases: propane, butane,
natural gas
Liquids: gasoline, paint
thinners, kerosene
Solids: gunpowders,
flares, high explosives,
flashpowder

45. Webinar - Arson Investigation Techniques - Detecting and examining evidence following a fire

46. Forensics Uncovered - Evidence Detection at an Arson
Scene - foster+freeman

47. DFES After the Fire - Fire Investigation Walk Through: https://www.youtube.com/watch?v

48. Fire Investigation
https://www.youtube.com/watch?v=SmmAh87Anh8

55. https://www.youtube.com/watch?v=bGthhTCsT5I

56. https://epgp.inflibnet.ac.in/Home/ViewSubject?catid=eCJfy23Kjy3c0vICLa6VYg==

57. exhibit must be
broken/cut down into
small pieces and
suitable amount of
sample for steam
distillation
30 ml of distillate
( presence of
flammable petroleum
products)
distillate is extracted
with approximately 30
ml of diethyl ether in
2-3 extractions
Combine the extracts
and concentrate by
evaporating the
extract at room
temperature to a small
volume (0.5 to 1 ml).
Extraction of Exhibits/Sample

59. GC-MS CONDITION
Column:
Pack SE – 30, Apiezon L or its equivalent column
Detector: Flame Ionization Detector (FID)
Nitrogen or Helium / 30 mL/min
Oven Temperature