To illustrate this fact, Sachtleben pairs demonstrations of commercial and military explosives with homemade materials in improvised explosives courses for bomb technicians at the Center for Improvised Explosives Research and Training at the Oklahoma State University Center for Health Sciences. The demos compare and contrast the materials' destructive powers and distinctive characteristics.
"We show commercially manufactured military-type explosives and follow with improvised explosives," Sachtleben says. "In many instances you can't tell the two apart. It is possible to cook up something in your kitchen that is just as powerful as that block of C4 used by the military or that stick of dynamite used in a rock quarry."
The risk multiplies when one considers that individuals with little understanding of explosives are whipping up these volatile concoctions. "Improvised explosives have no quality control. There is no repeatability. The way they are made—every time they are made—is a little bit different," says Sachtleben, a retired FBI agent who led a team investigating the Oklahoma City bombing and was on the entry team at Unabomber Ted Kaczynski's Montana cabin.
The 2010 "Bomb Factory" house in Escondido, Calif., is a sobering reminder of the safety hazard homemade explosives pose. It was discovered by a gardener stepping on a small amount of explosive material in the backyard causing it to detonate. The gardener lived but suffered severe injuries to his left eye, torso, and arm.
Compounding the relative ease of manufacture is the fact that experimenters produce homemade explosives from common household chemicals that when mixed become explosive, according to Jermain. "These mixtures contain an oxidizer and a fuel that are either mechanically mixed together or molecularly bonded during a chemical reaction," he says.
Homemade explosives are generally grouped into three categories based on the main oxidizer present: chlorates/perchlorates, nitrates, and peroxides.
Of these three categories, peroxide explosives are the most sensitive. Although hydrogen peroxide in concentrated forms can be mixed with various organic fuels to form explosive mixtures, it is more commonly used in chemical reactions to make triacetone triperoxide (TATP) and hexamethylene triperoxide diamine (HMTD). When hydrogen peroxide is mixed with either acetone or hexamine (fuel tablets), it forms a dangerous primary explosive, which is highly sensitive to heat, shock, and friction.
Jermain points out these precursors, such as hydrogen peroxide or acetone, can be purchased from numerous sources without suspicion. The materials can be found in rather innocuous places such as the local pool cleaning and maintenance store, the beauty supply shop, or the hardware store.
To emphasize this point, Sachtleben uses readily available ingredients when cooking up explosive education for bomb technicians. "We could buy chemicals in laboratory-type containers and use them in our class but we don't," he says. "We go to pool supply, beauty supply, hobby, and hardware stores and buy the actual products people might use so students can see them in their native condition. That's very important because they know how the experimenters are going to have them. They’re not going to buy them from the chemical supply warehouse; they’re going to buy them from local suppliers."
Detection Begins at Home
Because these materials are readily available within the community, Scott Zimmerman, owner of K17 Security, a Washington, D.C.-based firm providing security, personal protection services, and training to law enforcement, encourages police to work with local businesses to create a business watch that operates similar to a neighborhood watch. "This will allow businesses that sell items commonly used in improvised explosives to stay in contact with one another via a Yahoo talk group, e-mail list, blog, Facebook page, or any other means they find suitable," he says. "It is important for businesses to work together because these individuals do not want to arouse suspicion so it is common to buy smaller quantities from several different stores."