Instrumentation & Measurement Magazine 24-1 - 23

was attributable to Hauptmann, thus contributing the accused A Forensic Chemist may search for and collect burnt and unbeing sent to the electric chair.
burnt material samples, extract the volatile hydrocarbons from
Modern Forensic Science is today an interdisciplinary field: them, and may use gas chromatography to separate the comvarious disciplines such as engineering, computer science, ponents of these samples.
entomology, anthropology, pathology, physics, nursing, and
During any investigation, the most probative evidence is
psychology, etc. all contribute to it. As a matter of fact, any dis- sent to the forensic laboratory, after the crime scene personnel
cipline, profession, or trade with an expertise that can help in may perform initial screening tests called presumptive tests
crime solving activities will fall under the umbrella of Foren- at the crime scene. These tests allow investigators to narrow
sic Science.
the field of the possibilities to a certain class of substances alRemembering that chemistry is the branch of science that though they are not specific enough to confirm the presence
deals with the study of the composition of matter and of its of specific compounds. This procedure helps to speed up the
different transformations, Forensic Chemistry is a specialized investigation.
sub-field of Forensic Science that involves the application of
techniques and principles of chemistry to the field of foren- Fields of Analysis
sic investigation, to aid in the resolution of legal matters [3]. Forensic Chemistry deals with the chemical analysis of a wide
Forensic Chemistry involves complex procedures of chemi- variety of physical evidence deriving from homicides, arsons,
cal analysis that are used to identify unknown substances, to assaults, robberies, frauds, etc. as shown in Fig. 2.
Due to the fact that organic and inorganic analyses have
detect the presence or absence of controlled substances. The
identification procedures are based on the physical and chem- to be performed, a wide range of analytical techniques are
ical properties of the unknown substance supported by the generally employed in forensic analyses, to conduct both presumptive and confirmatory tests that serve as the basis for
analytical data [4].
As a matter of fact, many forensic scientists are chemists, criminal proceedings and help to determine sentencing for
who employ their knowledge of chemistry to analyze evidence convicted offenders. The choice of the proper technique and
that can be found on materials such as drugs, fibers, paint, soil, instrumentation to be used depends on the type of sample to
charred debris, glass, documents, paper, tool marks, firearms, be analyzed.
explosives, etc. Forensic Chemists, thanks to their knowledge
in toxicology, fingerprints, footwear impressions, tire impres- The Method of Analysis
sions, hair analyses, etc., may perform different analyses by All of the above-mentioned analyses are based on the princimeans of traditional and innovative analytical techniques to ples of the scientific method, which begins with observations:
determine the nature and composition of evidence collected Forensic Chemists attempt to organize observations and look
from the crime scene and compared with the control sam- for trends or patterns, suggest a hypothesis that tentatively
ples, when required. Forensic Chemists, when called on in the explains what is being observed and devise a plan to test the
hypothesis. They carry out the plan, making further obsercourts, have to provide testimony as expert witnesses.
The first principle of crime scene investigation is that vations, and if the new observations contradict the original
every contact leaves a trace. Consequently, for a correct hypothesis, a new hypothesis is suggested and tested, and
evaluation of the crime scene, it is fundamental that phys- the cycle continues until the hypothesis has been sufficiently
ical evidence is properly sampled, packaged and sealed in validated.
special containers. The integrity of evidence has to
be maintained and any further contamination has to
be avoided, except for their
natural contaminants such
as dirt and debris that are
often present.
Every substance that is
collected from the scene of
crime has a unique composition that can ultimately
be identified. Arsonists, as
an example, often use accelerants such as kerosene
or gasoline to accelerate
the rate of combustion,
and each accelerant has its
Fig. 2. Forensic Chemistry: physical evidence collected on the crime scene and analytical techniques utilized by Forensic
Chemists for their analysis.
own unique composition.
February 2021	

IEEE Instrumentation & Measurement Magazine	23



Instrumentation & Measurement Magazine 24-1

Table of Contents for the Digital Edition of Instrumentation & Measurement Magazine 24-1

No label
Instrumentation & Measurement Magazine 24-1 - No label
Instrumentation & Measurement Magazine 24-1 - Cover2
Instrumentation & Measurement Magazine 24-1 - 1
Instrumentation & Measurement Magazine 24-1 - 2
Instrumentation & Measurement Magazine 24-1 - 3
Instrumentation & Measurement Magazine 24-1 - 4
Instrumentation & Measurement Magazine 24-1 - 5
Instrumentation & Measurement Magazine 24-1 - 6
Instrumentation & Measurement Magazine 24-1 - 7
Instrumentation & Measurement Magazine 24-1 - 8
Instrumentation & Measurement Magazine 24-1 - 9
Instrumentation & Measurement Magazine 24-1 - 10
Instrumentation & Measurement Magazine 24-1 - 11
Instrumentation & Measurement Magazine 24-1 - 12
Instrumentation & Measurement Magazine 24-1 - 13
Instrumentation & Measurement Magazine 24-1 - 14
Instrumentation & Measurement Magazine 24-1 - 15
Instrumentation & Measurement Magazine 24-1 - 16
Instrumentation & Measurement Magazine 24-1 - 17
Instrumentation & Measurement Magazine 24-1 - 18
Instrumentation & Measurement Magazine 24-1 - 19
Instrumentation & Measurement Magazine 24-1 - 20
Instrumentation & Measurement Magazine 24-1 - 21
Instrumentation & Measurement Magazine 24-1 - 22
Instrumentation & Measurement Magazine 24-1 - 23
Instrumentation & Measurement Magazine 24-1 - 24
Instrumentation & Measurement Magazine 24-1 - 25
Instrumentation & Measurement Magazine 24-1 - 26
Instrumentation & Measurement Magazine 24-1 - 27
Instrumentation & Measurement Magazine 24-1 - 28
Instrumentation & Measurement Magazine 24-1 - 29
Instrumentation & Measurement Magazine 24-1 - 30
Instrumentation & Measurement Magazine 24-1 - 31
Instrumentation & Measurement Magazine 24-1 - 32
Instrumentation & Measurement Magazine 24-1 - 33
Instrumentation & Measurement Magazine 24-1 - 34
Instrumentation & Measurement Magazine 24-1 - 35
Instrumentation & Measurement Magazine 24-1 - 36
Instrumentation & Measurement Magazine 24-1 - 37
Instrumentation & Measurement Magazine 24-1 - 38
Instrumentation & Measurement Magazine 24-1 - 39
Instrumentation & Measurement Magazine 24-1 - 40
Instrumentation & Measurement Magazine 24-1 - 41
Instrumentation & Measurement Magazine 24-1 - 42
Instrumentation & Measurement Magazine 24-1 - 43
Instrumentation & Measurement Magazine 24-1 - 44
Instrumentation & Measurement Magazine 24-1 - 45
Instrumentation & Measurement Magazine 24-1 - 46
Instrumentation & Measurement Magazine 24-1 - 47
Instrumentation & Measurement Magazine 24-1 - 48
Instrumentation & Measurement Magazine 24-1 - 49
Instrumentation & Measurement Magazine 24-1 - 50
Instrumentation & Measurement Magazine 24-1 - 51
Instrumentation & Measurement Magazine 24-1 - 52
Instrumentation & Measurement Magazine 24-1 - 53
Instrumentation & Measurement Magazine 24-1 - 54
Instrumentation & Measurement Magazine 24-1 - 55
Instrumentation & Measurement Magazine 24-1 - 56
Instrumentation & Measurement Magazine 24-1 - Cover3
Instrumentation & Measurement Magazine 24-1 - Cover4
https://www.nxtbook.com/allen/iamm/26-6
https://www.nxtbook.com/allen/iamm/26-5
https://www.nxtbook.com/allen/iamm/26-4
https://www.nxtbook.com/allen/iamm/26-3
https://www.nxtbook.com/allen/iamm/26-2
https://www.nxtbook.com/allen/iamm/26-1
https://www.nxtbook.com/allen/iamm/25-9
https://www.nxtbook.com/allen/iamm/25-8
https://www.nxtbook.com/allen/iamm/25-7
https://www.nxtbook.com/allen/iamm/25-6
https://www.nxtbook.com/allen/iamm/25-5
https://www.nxtbook.com/allen/iamm/25-4
https://www.nxtbook.com/allen/iamm/25-3
https://www.nxtbook.com/allen/iamm/instrumentation-measurement-magazine-25-2
https://www.nxtbook.com/allen/iamm/25-1
https://www.nxtbook.com/allen/iamm/24-9
https://www.nxtbook.com/allen/iamm/24-7
https://www.nxtbook.com/allen/iamm/24-8
https://www.nxtbook.com/allen/iamm/24-6
https://www.nxtbook.com/allen/iamm/24-5
https://www.nxtbook.com/allen/iamm/24-4
https://www.nxtbook.com/allen/iamm/24-3
https://www.nxtbook.com/allen/iamm/24-2
https://www.nxtbook.com/allen/iamm/24-1
https://www.nxtbook.com/allen/iamm/23-9
https://www.nxtbook.com/allen/iamm/23-8
https://www.nxtbook.com/allen/iamm/23-6
https://www.nxtbook.com/allen/iamm/23-5
https://www.nxtbook.com/allen/iamm/23-2
https://www.nxtbook.com/allen/iamm/23-3
https://www.nxtbook.com/allen/iamm/23-4
https://www.nxtbookmedia.com