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Interpretation of Fire Debris Analysis
E Stauffer, Commissariat d’Identification Judiciaire, Police Cantonale Fribourg, Fribourg, SwitzerlandN NicDae id, University of Strathclyde, Glasgow, UK
ã 2013 Elsevier Ltd. All rights reserved.
Glossary Aliphatic An organic compound which is not aromatic;
organic compounds that are alkanes, alkenes, and alkynes
and their derivatives.
Alkane A saturated hydrocarbon compound having the
general formula Cn
H2nþ2.
Aromatics A class of unsaturated organic compounds that
have a benzene ring or that have chemical properties similar
to benzene as part of their structure.
Combustion products The set of products that are released
during the combustion reaction of materials. These products
are the result of both complete and incomplete combustion
but not of the pyrolysis process.
Crude oil Naturally occurring oil consisting primarily of
hydrocarbons with some other elements such as sulfur,oxygen, and nitrogen. Source material of nearly all
petroleum products.
Fire debris A generic term commonly used to describe
material collected at a fire scene and submitted to the
laboratory for ignitable liquid residue analysis.
Gasoline A mixture of several hundreds of volatile
hydrocarbons ranging from C4 to C12 used in an internal
combustion engine.
Ignitable liquid A liquid fuel that is either flammable or
combustible.
Ignitable liquid residues The remaining portion of an
ignitable liquid on a substrate after undergoing physical
and/or chemical changes.
Interfering products The set of chemicals found in a sample
that interferes with the proper identification of ignitable
liquid residues.
Isoparaffinic products An ASTM class of
petroleum distillate almost exclusively composed of
branched alkanes.
Microbial degradation The decomposition of petroleum
products by bacterial action that can diminish some
components relative to others resulting in an altered
chromatographic pattern that may not allow for a definitivecharacterization.
Petroleum distillates An ASTM class of products obtained
primarily from the fractionation of crude oil.
Pyrolysis products The set of products generated by the
process of pyrolysis only.
Substrate The sample material from
which a substance of interest (analyte) is removed
for analysis.
AbbreviationsGC Gas chromatography or gas chromatograph
IL Ignitable liquid
ILR Ignitable liquid residues
MS Mass spectrometry or mass spectrometer
Introduction
Once the chromatogram has been obtained, it is time to con-
duct the most difficult part of fire debris analysis: the inter-
pretation of the results. It is necessary to distinguish the
interpretation of chromatograms obtained from neat liquids
from the ones obtained from fire debris samples. In the first
case, the neat liquid is simply diluted and injected. As such,
there are almost no influences to take into account in the
interpretation. In the second case, the debris is first subjected
to an extraction (passive headspace, solvent, etc.) and then
analyzed. In addition, interfering products are coextracted
with ignitable liquid residues (ILRs). Thus, the interpretation
of the chromatogram is much more complicated.
The goal of the interpretation of the results is to determine
whether or not ILRs are present in the fire debris sample. In
order to achieve this, one will have to study the chromatogram
for patterns exhibited by known ignitable liquids (ILs).
Because thousands of different ILs with different compo-
nents exist, a system of organizing them into groups and
finding common patterns exhibited within each group had to
be devised. This led to a classification system, now described in
the ASTM standard test method for ILR in extracts from fire
debris samples by gas chromatography–mass spectrometry
(GC–MS) E1618. As a result, these patterns are well known
and the process of interpretation is clearly described.
Classification
While one may think that hundreds of thousands of differ-
ent ILs potentially used at fire scenes may exhibit as many
different patterns, this is not the case. First of all, most ILs
are petroleum based, that is, they are derived from crude
oil. As such, most of them are composed exclusively of
aliphatic and/or aromatic compounds. Second, because
the processes of transforming crude oil into refined prod-
ucts are not very diverse, patterns exhibited by petroleum-
based ILs can be placed into six different classes of ILs, each
with a characteristic set of patterns . Finally, when dealing
with nonpetroleum-based ILs, even though all possibilities
Encyclopedia of Forensic Sciences, Second Edition http://dx.doi.org/10.1016/B978-0-12-382165-2.00102-1 183
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are open, these liquids usually consist of only a few differ-
ent components. Thus, the resulting chromatograms are not
as complicated as those from petroleum-based ILs, which
can exhibit several hundreds of components.
ASTM standard E1618 proposes a classification system
based on eight different classes, as shown in Table 1.
The examples for each class are not exhaustive; they are just
the most commonly encountered products found in each
Table 1 ASTM E 1618–10 ignitable liquid classification scheme
Class Light (C 4 –C9 ) Medium (C 8 –C13 ) Heavy (C 8 –C 20þ )
Gasoline Fresh gasoline is typically in the range of C4–C12
Petroleum distillates (including
dearomatized)
Petroleum ether
Some cigarette lighter fluids
Some camping fuels
Some charcoal starters
Some paint thinners
Some dry cleaning solvents
Kerosene
Diesel fuel
Some jet fuels
Some charcoal starters
Isoparaff inic products Av iation gasSome specialty solvents
Some charcoal startersSome paint thinners
Some copier toners
Some commercial specialtysolvents
Naphthenic paraffinic products Cyclohexane-based solvents/products Some charcoal starters
Some insecticide vehicles
Some lamp oils
Some insecticide vehicles
Some lamp oils
Industrial solvents
Aromatic products Some paint and varnish removers
Some automotive parts cleaners
Xylene-based products
Toluene-based products
Some automotive part cleaners
Specialty cleaning solvents
Some insecticide vehicles
Fuel additives
Some insecticide vehicles
Industrial cleaning solvents
Normal alkane products Solvents: pentane, hexane, heptane Some candle oils
Some copier toners
Some candle oils
Carbonless forms
Some copier toners
Oxygenated solvents Alcohols
KetonesSome lacquer thinners
Fuel additives
Surface preparation solvents
Some lacquer thinners
Some industrial solventsMetal cleaners/gloss removers
Others/miscellaneous Single-component products
Some blended products
Some enamel reducers
Turpentine products
Some blended products
Some specialty products
Some blended products
Some specialty products
Carbon #
6
2
Benzene
Toluene
C2-alkylbenzenes
C3-alkylbenzenes
C4-alkylbenzenes
0
200000
400000
600000
800000
1000000
A b u n d a n c e
3 4 5 6 7 8 9 10
7 8 9 10 11 12 13 14 15
11 12 13 14 15
16 17 18 19 20 21 2 2 23 24 25
Time
Figure 1 Chromatogram of a neat gasoline (unweathered). Time in minutes. Reproduced from Stauffer E, Dolan JA, and Newman R (2008) Fire
Debris Analysis , p. 323. Burlington, MA: Academic Press. ã Elsevier.
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particular class. In his/her findings, the fire debris analyst does
not report a finished product itself, but rather the ASTM class.
Then, products found in that class can be cited as examples, to
guide the fire investigator.
Because the difference between the classes relies on the chem-
ical composition of the IL, theASTM system introduces a second
dimension of classification to refine the different categories: the
boiling point range. By using the boiling point range, one can
Carbon #
A b u n d a n c e
A b u n d a n
c e
A b u n d a n c e
Carbon #
Light petroleum distillate
Medium petroleum distillate
Heavy petroleum distillate
Carbon #
6
2 3 4 5 6 7 8 9 10
7 8 9 10 11 12 13 14 15
11 12 13 14 15
16 17 18 19 20 21 2 2 23 24 25
6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25
6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25
Time
Figure 2 Chromatograms of light, medium, and heavy petroleum distillates. Time in minutes. Reproduced from Stauffer E, Dolan JA, and Newman R
(2008) Fire Debris Analysis, p. 328. Burlington, MA: Academic Press. ã Elsevier.
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refine the different classes and create more pertinent categories.
In practice, the light subclass ranges approximately from 0 to
150 C, the medium from 120 to 240 C, and the heavy
from 120 C to more than 350 C. The only exception to
that subclassification is gasoline, whose boiling point range
does not vary greatly. This classification system works per-
fectly well with the separation and analysis obtained by
GC–MS as this instrument separates the compounds based
on their boiling points and the MS provides identification of
their chemical nature.
A b u n d a n c e
Carbon #
Carbon #
Carbon #
6
2 3 4 5 6 7 8 9 10
7 8 9 10 11 12 13 14 15
11 12 13 14 15
16 17 18 19 20 21 22 23 24 25
Time
6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25
6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25
A b u n d a n c e
A
b u n d a n c e
Light isoparaffinic product
Medium isoparaffinic product
Heavy isoparaffinic product
Figure 3 Chromatograms of light, medium, and heavy isoparaffinic products. Time in minutes. Reproduced from Stauffer E, Dolan JA, and
Newman R (2008) Fire Debris Analysis, p. 332. Burlington, MA: Academic Press. ã Elsevier.
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Interpretation of Neat Liquids
With petroleum-based products, the basic principle of
interpretation is to evaluate the chromatogram for the pres-
ence, distribution, boiling point range, and relative abun-
dance of all saturated aliphatics and all aromatics. With
nonpetroleum-based products, the analyst looks at all com-
pounds present in the chromatogram and evaluates whether
or not they could originate from an IL.
While an advanced knowledge of crude oil-refining processes
is necessary to fully understand the reasons behind the chemical
compositions of the different ASTM classes, this goes beyond the
Carbon #
Carbon #
Light naphthenic paraffinic product
Medium naphthenic paraffinic product
Heavy naphthenic paraffinic product
6
A b u n d a n c e
A b u n d a
n c e
A b u n d a n c e
7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25
6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25
Carbon #
6
2 3 4 5 6 7 8 9 10 11 12 13 14 15 Time
7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25
Figure 4 Chromatograms of light, medium, and heavy naphthenic paraffinic products. Time in minutes. Reproduced from Stauffer E, Dolan JA,
and Newman R (2008) Fire Debris Analysis, p. 335. Burlington, MA: Academic Press. ã Elsevier.
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scope of thischapter.Nevertheless, it is possible to provide a rapid
overview of the different classes and their compositions.
Gasoline is mostly composed of aromatic compounds rang-
ing from C4 (4-carbon’long chain) to C12 (12-carbon’long
chain). It also contains some alkanes; however, they are nor-
mally not abundant. Figure 1 shows an example of a chro-
matogram of gasoline.
Petroleum distillates are the closest products to crude oil,
as they have undergone a minimum of refinement. They
contain both aliphatics and aromatics in a normal (Gaussian)
distribution with spiking n-alkanes. Some petroleum distil-
lates said to be dearomatized have no aromatic content.
Figure 2 shows examples of light, medium, and heavy petro-
leum distillates.
Carbon #
Carbon #
Carbon #
Heavy aromatic product
Medium aromatic product
Light aromatic product
A b u n d a n c e
A b u n d a n
c e
A b u n d a n c e
6
2 3 4 5 6 7 8 9 10 11 12 13 14 15 Time
7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25
6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25
6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25
Figure 5 Chromatograms of light, medium, and heavy aromatic products. Time in minutes. Reproduced from Stauffer E, Dolan JA, andNewman R (2008) Fire Debris Analysis, p. 339. Burlington, MA: Academic Press. ã Elsevier.
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Isoparaffinic products are exclusively constituted of isoalk-
anes as shown in Figure 3. They have no aromatics, n-alkanes,
or cycloalkanes.
Naphthenic paraffinic products are comprised of cycloalk-
anes and isoalkanes (see Figure 4). Basically, a naphthenic
paraffinic product is a petroleum distillate in which the
n-alkanes and the aromatic content have been removed.
Aromatic products are composed exclusively of aromatic
compounds. As a matter of fact, such a product is constituted
of the aromatic fraction that was isolated from crude oil. In
general, they exhibit a narrow boiling point range, as shown
in Figure 5.
n-Alkane products represent the simplest pattern: a narrow
fraction of n-alkanes (usually not spanning more than four or
five carbons). Figure 6 shows an example of light, medium,
and heavy n-alkane products.
Oxygenated solvents include all ILs containing at least one
oxygenated compound in large excess of the rest of the com-
ponents (at least one order of magnitude in the chromato-
gram). Oxygenated solvents may also contain other ILs such
Carbon #
Carbon #
Carbon #
6
2 3 4 5 6 7 8 9 10 11 12 13 14 15 Time
7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25
6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25
6 7 8 9 10 11 12 13 14 15 16
Medium to heavy normal-alkane product
ExxonMobil Norpar 12
Heavy normal-alkane product
ExxonMobil Norpar 13
Heavy normal-alkane product
ExxonMobil Norpar 15
17 18 19 20 21 22 23 24 25
A b u n d a
n c e
A b u
n d a n c e
A b u n d a n c e
Figure 6 Chromatograms of light, medium, and heavy n-alkanes. Time in minutes. Reproduced from Stauffer E, Dolan JA, and Newman R (2008)
Fire Debris Analysis, p. 337. Burlington, MA: Academic Press. ã Elsevier.
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as medium petroleum distillates. Figure 7 shows three exam-
ples of oxygenated solvents.
Miscellaneous products include ILs that do not fit in any of
the categories previously described. Figure 8 shows an example
of a turpentine, which is classified as miscellaneous.
In summary, Table 2 shows the different components
found in each ASTM class and subclass.
While the interpretation and classification of chromato-
grams may appear relatively complex at first, it is in fact quite
easy with neat liquids. Figure 9 provides a guide to the proper
interpretation of chromatograms. If the analyst follows this
guide, there should be no problem in correctly identifying
neat liquids. Unfortunately, it is a whole other story with ILR
from fire debris samples.
Carbon #
Carbon #
Carbon #
6
2 3 4 5 6 7 8 9 10 11 12 13 14 15 Time
7 8
Toluene
Toluene
2-Propoxyethanol
2-Propyl acetate
n-Propyl acetate
n-Butoxy ethanol
2-Ethoxy
ethanol
1-Butanol
n-Butyl acetate
2-Ethoxyethyl acetate
n-Butyl butyrate
9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25
6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25
6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21
Light to medium oxygenated solvent
DuPont fast dry acrylic lacquer thinner
Light oxygenated solvent + light aromatic productUSA Brand lacquer thinner
Light oxygenated solvent + light aromatic productDyco solvent E-5
22 23 24 25
A b u n d a n c e
A b u n d a n
c e
A b u n d a n c e
Figure 7 Chromatograms of light, medium, and heavy oxygenated solvents. Time in minutes. Reproduced from Stauffer E, Dolan JA, andNewman R (2008) Fire Debris Analysis, p. 342. Burlington, MA: Academic Press. ã Elsevier.
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Interpretation of Ignitable Liquid Residues
When an IL is poured onto a substrate, and then set on fire,
extinguished, collected, and finally extracted, one can easily
imagine that it no longer exhibits the same chromatographic
pattern as when it was neat. This is the reason why the
interpretation of ILR is much more complicated than that
of mere IL, in addition to the fact that the analyst does not
know at first whether or not ILR are present in the debris.
There are several parameters influencing the composition of
the ILR extract from a fire debris as shown in Figure 10.
First, the substrate itself may already contain some IL, or
at least some compounds that are found in IL. These are
called precursory products and they may be due to the raw
material constituting the substrate, to its manufacturing pro-
cess, to the setup in its final position/use, and to some
natural or accidental contaminations. For example, some
woods contain terpenes, compounds typically found in
Carbon #6
20
2000000
4000000
6000000
8000000
3 4 5
Camphene
1,4-Cineol d-Limonene
o-Cymene
a-Pinene
a-Terpinene
g-Terpinene
6 7 8 9 10 11 12 13 14 15 Time
7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25
A b u n d a n c e
Figure 8 Chromatogram of turpentine product, classified as miscellaneous. Time in minutes. Reproduced from Stauffer E, Dolan JA, and
Newman R (2008) Fire Debris Analysis, p. 344. Burlington, MA: Academic Press. ã Elsevier.
Table 2 The different components found in each ASTM class and subclass
Class Alkanes Cycloalkanes Aromatics (including indanes) Polynuclear aromatics
Gasoline Present, less abundant than
aromatics
Present, less
abundant than
aromatics
Abundant Present
Petroleum
distillates
Abundant, normal (Gaussian)
distribution
Present, less
abundant thanalkanes
Present, less abundant than
alkanes (absent indearomatized distillates)
Present (depending on boiling point range),
less abundant than alkanes (absent indearomatized distillates)
Isoparaffinic
products
Branched alkanes abundant,
n-alkanes absent or strongly
diminished
Absent Absent Absent
Naphthenic
paraffinic
products
Branched alkanes abundant,
n-alkanes absent or strongly
diminished
Abundant Absent Absent
Aromatic
products
Absent Absent Abundant Abundant (depending on the boiling point
range)
Normal
alkanes
products
Abundant Absent Absent Absent
Oxygenated
solvents
Composition may vary, presence of oxygenated organic compounds
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thinners. Most outsoles are glued to the shoe and this glue
usually contains an aromatic compound, such as toluene. A
carpet is also often glued to the floor; however, this glue
usually contains a medium petroleum distillate. When one
sprays insecticides around a baseboard, these become con-
taminated with a naphthenic paraffinic or an aromatic prod-
uct. These are all examples of precursory products that may
be found on a substrate before it is even deliberately contam-
inated with an IL used as an accelerant.
Second, once an IL is poured onto a substrate, it will un-
dergo three effects, which will influence its composition:
weathering, diminution, and degradation. Weathering is the
effect of the evaporation of an IL. Because an IL is commonly made of many differentcompounds of different boiling points,
not all compounds will evaporate at the same rate. As such, the
chromatographic pattern of a neat IL (unweathered) is differ-
ent from that of its 50% evaporated version. As a matter of fact,
as the weathering increases, the chromatogram moves to the
right, meaning that the light compounds disappear and
the heavy compounds become more and more dominant.
Diminution represents the uniform loss of the different com-
pounds of an IL. In practice, it occurs simultaneously with
weathering, but it may also be due to poor evidence collection
or to fire suppression activities. Finally, degradation occurs
when the substrate, mostly soil, contains proteobacteria,
which are capable of degrading petroleum-based IL. These
bacteria, depending on their type, will selectively degrade ali-
phatics or aromatics. As a result, the composition of an IL may
drastically change, not based on its boiling point range, but
rather on its chemical characteristics.
Third, when a substrate burns, pyrolysis and combustion
products are created. Pyrolysis products consist of compounds
that are often the same as the ones found in petroleum prod-
ucts. As a result, they strongly interfere with the chemical
composition of an IL, making it impossible in some instances
to properly identify an ILR. Most commonly encounteredpyrolysis products are toluene, styrene, naphthalene, benzal-
dehyde, ethylbenzene, indene, phenylethyne, m,p-xylenes, 1-
and 2-methylnaphthalene, acetophenone, and the series of
alkane–alkene–alkadiene ranging from C10 to C16. Figure 11
shows an example of pyrolysis products created with burned
polyethylene.
Combustion products usually do not interfere as much as
pyrolysis products with ILR because they are oxidized products,
which are not often found as IL components. Because they are
very light compounds, they tend not to be trapped in substrates.
Figure 9 Petroleum-based ignitable liquid flow chart. Every question related to the presence of specific compounds implies that these compounds
must be present in the proper pattern (as compared to a pattern of these compounds from a reference liquid analyzed on the same system). * Or “Are
cycloalkanes distinctively present in the extracted ion chromatograms”? Reproduced from Stauffer E, Dolan JA, and Newman R (2008) Fire Debris
Analysis, p. 345. Burlington, MA: Academic Press. ã Elsevier.
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Finally, fire suppression agents may also be used by the
intervening fire department. Some of these agents may also
contribute to the fire debris extract, such as some foams that
use D-limonene or some alcohol-based compounds.
Interfering products, then, are a set of products comprising
precursory, pyrolysis, combustion, and fire suppression prod-
ucts. When interpreting chromatograms of extracts from fire
debris samples, one must account for the presence of these
interfering products. In addition, one must not forget thedifferent effects occurring directly on the IL. This is why a
systematic approach was developed.
Systematic Approach
Because the interpretation of chromatograms for ILR identifi-
cation is quite complicated, it is important to follow a system-
atic approach, which is constituted of the six following steps:
1. Identify the sample and its substrate.
2. Estimate the typical contribution from that substrate.
3. Determine to which influences the substrate was subjected.
4. Estimate the effect of these influences.
5. Study the chromatogram from start to finish, including
peak identification.
6. Study extracted ions in the regions of interest, including
peak identification.
Even if the fire debris analyst did not work on the fire scene,
he/she must have some clear basic knowledge about the sam-
ple in question, particularly in regard to its composition, its
environment at the time of the fire, and the different steps it
underwent. Knowledge of the sample’s history is crucial, too.
Raw material
Manufacture
Set-up
Natural/accidentalcontamination
Deliberate
contamination
Fire
Fire suppression
Collection
Transportation
Analysis
Degradation
Fire
suppression
products
Diminution
Weathering
Ignitable liquid
Precursory
products
Pyrolysis
products
Combustion
products
Figure 10 The different steps (in the middle) to which the fire
debris sample is subjected from its creation to its analysis, along with
the influences (on the left) on the potential ignitable liquid present
in the debris and the different interfering products created
(on the right). Reproduced from Stauffer E, Dolan JA, and Newman R
(2008) Fire Debris Analysis, p. 443. Burlington, MA: Academic Press.
ã Elsevier.
Carbon #
6
2
C6
C7
C8C9
C10
C11C12
C13
C14
C16
C15
C17
C18
C20
03 4 5 6 7 8 9 10 11 12 13 14 15 Time
7 8 9 10 11 12 13 14 15 16 17 18 19 20
1000000
2000000
3000000
A b u n d a n c e
Figure 11 Chromatogram of polyethylene pyrolysis products. Time in minutes. Reproduced from Stauffer E, Dolan JA, and Newman R (2008)
Fire Debris Analysis, p. 459. Burlington, MA: Academic Press. ã Elsevier.
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The preliminary examination of fire debris samples is, thus, a
very crucial step that should never be undermined.
Significance of Findings
Fire debris analysis is an extremely complex science and the
reason is twofold. First, the interpretation of chromatograms is
rendered very difficult due to the numerous components of many different IL and the presence of interfering products. The
second reason is that the simple presence of ILR in a debris does
not imply at all that it was used as an accelerant in the fire. This
last determination requires the experience of both the fire debris
analyst and thefire investigator, as wellas a verygood knowledge
of the fire scene and the circumstances surrounding the fire.
See also: Chemistry/Trace/Fire Investigation: Analysis of Fire
Debris; Chemistry of Fire; Thermal Degradation; Methods: Gas
Chromatography; Gas Chromatography–Mass Spectrometry; Mass
Spectrometry.
Further Reading
ASTM International (2010) ASTM E1618-10 Standard Test Method for Ignitable Liquid Residues in Extracts from Fire Debris Samples by Gas Chromatography-Mass
Spectrometry , Annual Book of ASTM Standards 14.02. West Conshohocken, PA:ASTM International.
Byron DE (2002) The effects of surfactants and microbes on the identification ofignitable liquids in fire debris analysis. Fire and Arson Investigator 53(1): 50ss.
DeHaan JD, Brien DJ, and Large R (2004) Volatile organic compounds fromthe combustion of human and animal tissue. Science and Justice 44(4):223–236.
DeHaan JD and Icove DJ (2011) Kirk’s Fire Investigation, 7th edn. Upper Saddle River,NJ: Pearson Education.
Gilbert MW (1998) The use of individual extracted ion profiles versus summed
extracted ion profiles in fire debris analysis. Journal of Forensic Sciences 43(4):871–876.
Leffle WL (2000) Petroleum Refining in Nontechnical Language, 3rd edn. Tulsa, OK:PennWell Corporation.
Lentini JJ, Dolan JA, and Cherry C (2000) The petroleum-laced background. Journal of Forensic Sciences 45(5): 968–989.
Mann DC and Gresham WR (1990) Microbial degradation of gasoline in soil. Journal of Forensic Sciences 35(4): 913–923.
McGee E and Lang TL (2002) A study of the effects of a micelle encapsulator firesuppression agent on dynamic headspace analysis of fire debris samples. Journal of
Forensic Sciences 47(2): 267–274.Newman R, Gilbert M, and Lothridge K (1997) GC-MS Guide to Ignitable Liquids. Boca
Raton, FL: CRC Press.Nic Daeid N (2004) Fire Investigation. Boca Raton, FL: CRC Press.Spreight JC (1999) The Chemistry and Technology of Petroleum , 3rd edn. New York,
NY: Marcel Dekker.Stauffer E (2003) Basic concept of pyrolysis for fire debris analysts. Science and Justice
43(1): 29–40.Stauffer E, Dolan JA, and Newman R (2008) Fire Debris Analysis. Burlington, MA:
Academic Press.Trimpe MA (1991) Turpentine in arson analysis. Journal of Forensic Sciences 36(4):
1059–1073.
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