The University of Rhode Island’s forensic science seminar series went off with a bang last Friday when FBI bomb expert, Kirk Yeager spoke on explosives. 

After earning a PhD from Cornell University in organic chemistry, Yeager went on do a post-doc at New Mexico Tech, where he later went on to become a researcher and eventually worked his way up to associate director.  After spending many years making explosives, the FBI began to take a keen interest in Yeager.

Yeager, who joined the FBI in 2000 as a senior scientist, was able to effectively deliver his seminar to chemistry majors and non-chemistry majors alike in a way that didn’t confuse the latter half of the room. Explaining his work in layman’s terms is something Yeager has had lots of experience with in his line of work, addressing police, fire, and juries.

During his time at the FBI, Yeager has appeared as an expert witness in as many 10 cases to his estimate, most of which pled out.  “The science part is easy,” Yeager said. “The communication and how things go back and forth in the legal system is what’s really difficult.”

In one of the cases that Yeager testified in, the best way to inform the jury of what could’ve happened was by showing them the potential explosion.  Filling a college dorm size fridge with explosive materials all created with easily available drug store materials, Yeager blew the fridge to unrecognizable bits. 

“When I show you what the person had and what it could do, where it was found, that makes an impression,” Yeager said. 

One of the most prominent bombing cases in our generation that Yeager has worked includes the Boston Marathon Bombings. 

Even though he didn’t give the audience the step-by-step directs to make a bomb, he did speak about the essential key components that go into on.  Explosives, or “materials that undergo a self-sustaining chemical reaction which gives off heat, rapidly giving off energy,” require three things: heat, fuel, and oxygen. 

Explosives, destructive in their nature, are most commonly seen in the form of dynamite, C-4, or TNT.  They cause intense pressurization, fragmentation, and thermal heat, which makes them a popular choice among terrorists, Yeager said. 

There are three types of bomb builders that take up the majority of Yeager’s time.  “I’ve got three demographics,” Yeager said. “I’ve got the good, the bad, and I’ve got the ugly.”

Terrorists get the most of the publicity, but curious adolescents also cause problems for the FBI because of the bridges that the Internet is able to build.  Sites like YouTube have allowed communication with and the education of terrorist groups, instructing them how to create bombs. Also causing problems for the FBI are what Yeager describes as the perennial adolescent demographic. 

“The youth of our country are aiding and abiding terrorists with out even realizing it,” Yeager said. 

Interestingly enough, the creation of explosives is not illegal on the federal level.  Once an explosion occurs, intentionally or not, it becomes a different story.

In his time in operational assets at the FBI, Yeager has traveled to six different continents, assessing bombing scenes. “I’ve been to more countries than I care to remember,” Yeager said.