Seattle Bomb Squad, ATF on bombs and investigations

SEATTLE -- The largest and only bomb squad with a dedicated staff in the state is located in Seattle. Their job requires a lot of quick decision making, depending on the type of explosive they are dealing.

“We constantly assess from the information we initially receive, what we see with our eyes, what we detect with instruments we may deploy and what we see on x-rays if we’re able to get those, all of those things factor into our final decision on how we’re going to render it safe,” said Sgt. Jim Hansen with the Seattle Bomb Squad.

The bomb squad’s first move is typically to deploy the robot, which gives investigators a look at a potentially explosive device from a safe distance. But if a bomb has radioactive or chemical elements, they may choose to use what’s called a foam tent to contain the blast.

“With the decon agent contained within the foam, it would destroy the chemical or biological agent,” Hansen said.

If the device is inside a building and their “total containment vessel” can fit in the elevator, it can be used to safely detonate an explosive. But because every bomb is unique, these technicians have to make a judgment call every time they are deployed -- the Boston bombs for instance were homemade, which made it extremely difficult for investigators to determine exactly what materials were used.

“We’re talking about improvised devices. We’re not talking about military explosives that are made to an identified standard and have specific protocols for disarming and deactivating those," Hansen said. "We’re talking about something somebody thought up in their head, and used materials that they were able to get a hold of, and they constructed it in a way that’s non- standard."

“The fact that there were allegedly ball bearings and nails and things of that nature in this device very clearly tells you that someone was out there willing and able to harm people and that was their intention,” ATF regional director Kelvin Crenshaw said.

While bomb techs work to reconstruct the Boston devices through fragments, the ATF is working with the FBI to find who was responsible for placing the bombs.

“We certainly will have a heavy hand in the investigation. Every incident that we work that causes our American citizens harm or potential harm, we work those investigations together,” Crenshaw said.