Engineering and Calamity

Engineers through the ages have been skilled inventors and tend to think laterally by default, especially when presented with problems that need solutions. Often times, however, forensic engineers are needed for solutions that have turned into problems or catastrophic failures. Or when a calamitous event occurs. These may be the consequence of natural occurrences, such as earthquakes, but unfortunately also as a result of deliberate, malicious acts.

The Boston Marathon in the USA is the world's oldest marathon. It was first run in 1897 and tends to fall on the 3rd Monday in April. The 2013 race ran early last week and will be remembered, not for the winners, their speeds and their tales of tenacity and endurance, but for the deadly attacks at the finish line.

The aftermath of scenes of destruction such as this, tend to follow a pattern – despite the appearance of chaos and frenetic activity. Once the first dust settles; the necessary aid is provided to those in need, the area is cleared of people and teams of specialists are called to the scene. Forensic engineers make up a crucial part of the mix. The expertise required depends on the calamity, but ranges from metallurgy, mechanical, civil, chemical and electrical. The incidents requiring their attention are obviously numerous, but include scenarios such as failures of industrial equipment, gas and oil pipeline mischances and aviation and aerospace component defects and failures. And of course explosions and fire. They use the final conditions of a catastrophic event -  the available physical evidence -  in combination with the governing natural laws and attempt to establish cause. For example, in the TWA Flight 800 disaster in 1996, after much controversy, the forensic team discovered that a design defect in the centre fuel tank was responsible for the explosion which caused the crash.

After disasters such as the one in Boston, first and foremost forensic engineering skill is employed to identify the presence of any transient evidence. And then with their structural capabilities they ascertain safety concerns as a matter of urgency - particularly where imminent building collapse is a possibility. (Then down the track they are able to make recommendations for modifying structures to better withstand the extreme forces involved in earthquakes, bomb blasts and other deliberate attacks, such as the one on the World Trade Centre in 2001.)

Other aspects of the physical environment are also assessed, even odours. Anyone can sniff out something malodourous, but with some knowledge their detection can often quickly determine the presence of biological or chemical hazards (or the composition of the detonation). The human olfactory sense is obviously assisted, where necessary, by chemo sensors or gas chromatography.

Once the ground work has been completed the forensic teams retreat to collate their findings. If and when the facts are required in court the forensic engineer becomes an expert witness. Drawings and diagrams, computer graphics, 3-D animations and multi-media presentations clarify and demonstrate the relevant issues during their testimony. Furthermore, their documentation forms a permanent record of the incident, and aids in crime scene reconstruction.

“Engineers are needed everywhere!” Said my 15 year old son when I mentioned this article. A truism indeed.