Engineering Inc. - November/December 2009 - 20

T lumber falls and kills him—and witnesses saw it happen—there’s no need to conduct a forensic investigation.” On the other hand, if the strap broke, it’s important to find out whether the failure was the result of an overloaded strap, one that was improperly maintained or a manufacturing defect. “It might require testing a whole series of straps made at the same time to determine whether there was a problem in manufacturing,” Kochan explains. As projects become increasingly complex and, in many ways, more dangerous, the practice of forensic engineering has gone mainstream. “It has morphed from a few minor players handling cases in the late 1970s to larger and more highly specialized firms,” says Kochan. At Forensic Analysis & Engineering, more than 50 engineers and a handful of technical consultants and support staff handle hundreds of cases a year. The firm specializes in forensic engineering and forensic science cases. The latter often involves highly specialized testing of DNA evidence, fiber and paint analysis and ballistics trajectory tests, among other technical procedures. Investigations focus on civil and criminal cases, as well as manufacturing problems. A company, for example, might introduce a product and find that a component consistently fails or, at least, doesn’t perform to specifications. The manufacturer might hire a forensic engineering firm to determine whether the design of the component is at fault or something else is— such as the way a subsystem draws power or interacts within the larger electrical or mechanical framework. “In most cases, the information is useful because it provides a starting point for understanding all the various issues,” says Pence. Likewise, a building owner, manufacturer or government agency might find itself the target of a lawsuit as a result of an injury or accident. A forensic engineering team would then sift through all of the evidence and data in order to determine where the fault lies, or provide a forensic engineer who can serve as an expert witness in the event of a trial. Stroud, Pence & Associates has investigated construction collapses, vehicles that have crashed into buildings and defects that have prompted executives at different firms to point fingers at one another. “It’s across the board,” says Pence. Some cases prove tougher than others. Boating accidents are particularly challenging due to a lack of skid marks and other physical evidence. Often, the only clues forensic investigators have are visual evidence from debris and personal statements from witnesses. Fire investigations here usually are signs of a problem before a failure occurs. It’s often possible to reinforce the structure or fix the problems before they lead to a full-scale calamity. nILS V. ErIcSon di SALvo ericSon GrouP Tools oF The Trade A few of the systems, devices and approaches used by forensic engineers: • Computer simulations. Software, including proprietary systems, can re-create accidents and failures and provide sophisticated analysis. • Fluoroscopes and X-rays. these images, and other types of electromagnetic tests, can reveal structural weaknesses and other problems. • Fiber-optic cameras, borescopes and fiberscopes. Mounting a camera on a fiber-optic strand lets engineers peer inside walls, floors, ceilings, cracks and other hard-to-reach places. • Vibration sensors. these systems can uncover structural defects or weaknesses in concrete, metal and other substances. • Infrared spectroscopy. these devices can help forensic specialists document and analyze paint samples, chemicals in the atmosphere, fibers and other substances. • Chemical analysis. Used to detect changes in the composition of a substance, find mold or toxic substances, or measure corrosion. are equally challenging because usually much evidence is destroyed. Forensic specialists in these cases often find themselves sifting through trash, debris and microscopic remains to build a case. Kochan recalls one investigation involving a fishing vessel that exploded and sank off the coast of Hawaii. Manufacturers, law enforcement agencies and insurance companies all had a stake in the investigation. Forensic crews recovered the boat’s charred remains; they studied burn fragments and examined the nature of the explosion. Ultimately, “we were able to determine the specific point of ignition and the cause of the accident,” Kochan recalls. “The piping for a propane system had been improperly installed—it did not follow code. The constant vibration and salt air caused corrosion and eventually a leak.” In the world of forensic science, success requires a certain mindset. It’s not only vital for a firm to have a pool of experts on hand—typically, engineers with special technical knowledge—but it’s also vital that these individuals have experience and intuition. “The primary qualification to be a forensic engineer,” Pence says, “is to understand the big picture and be able to recognize what is relevant and what is not relevant. Though it’s important to understand codes and laws, it’s equally valuable to be able to read between the lines and recognize when something didn’t function ENGINEERING INC. NovEmbER / DECEmbER 2009

Engineering Inc. - November/December 2009

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