A “Toolbox” for Forensic Engineers

A “Toolbox” for
Forensic Engineers
4.1 Introduction
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A range of scientific instruments and techniques is necessary to “solve” the
variety of cases presented in the remaining chapters. Such procedures are
needed to obtain evidence about the products involved and the materials of
which they are made. In other words, “tools” must be selected that are
appropriate to report on the issues put to the investigator. The interpretation
of these data requires some expert knowledge. Furthermore, expert findings
must be presented in a form that lawyers can understand and incorporate
into their legal proceedings, as well as one that allows the courts to reach a
judgment.
The objective of any forensic engineering investigation is to determine
the cause or causes of accidents or failures. Forensic engineering is, therefore,
primarily a problem-solving exercise. With any analytical assignment, there
is a need to be aware of available tools, the information they provide, their
limitations and any “trade-offs” that may be inherent in a particular technique.
However, there is no pressing need to understand any deep underlying
theory, just as when driving a car it is not necessary to know the way a car
engine works.
Many failure problems will lead to litigation, perhaps because the damage
is capable of several different interpretations. Thus the approach taken to any
material evidence, such as a fractured component, is fundamentally constrained
by the need to preserve and conserve it for possible examination by
others. Items submitted for examination may be vital legal evidence that
cannot be chopped up or machined into test specimens. The exception is
where the item is very large, so selecting samples for test specimens will not