The Transportation Security Administration relies heavily on trained canines to screen passengers for explosive material. Under TSA supervision, the Post's Andrea Sachs conducted a training exercise at Reagan National Airport by strapping explosive material around her waist and testing the canine's ability to sniff out suspicious material. (Erin Patrick O'Connor/The Washington Post)

On a late December morning at Reagan National Airport, a traveler dressed casually in jeans, a striped shirt and winter boots passed a black dog sniffing a rack of potato chips. Seconds later, she heard the sound of toenails clicking against the hard floor. The noise grew closer and faster. She felt a wet nose press against her hand and watched a red rubber toy roll by. An exuberant Labrador bounded past her, retrieving his prize for a job well done.

Blue, a member of the Transportation Security Administration’s K-9 passenger-screening team, had uncovered explosives strapped to the stranger’s back. Potential disaster diverted — all for a chew on a Kong.

“Dogs live in a world of smell. This is their primary sense,” said Douglas Timberlake, a TSA explosives-detection canine handler who was overseeing the day’s training session. “They have the innate ability to keep the public safe.”

Government and local law enforcement agencies have employed canines — and their superpower snouts — for decades. The TSA, for instance, uses dogs to inspect cargo, aircraft, parked cars, abandoned bags and other stationary objects found in and around airports. Canines used by Customs and Border Protection snuffle around luggage coming off baggage carousels, searching for such banned goods as fresh produce, exotic wildlife, undeclared currency and illicit drugs. And four-legged soldiers with the Department of Defense scour war zones for improvised explosive devices and other deadly contraptions.

Five years ago, the TSA put its dogs on a new beat: passenger screening. More than 140 of the canines preside over security checkpoints at over 35 airports. By year’s end, the agency aims to more than double the number of furry participants and expand the program to more than 40 facilities.

Michael Johns, a canine handler with the Transportation Security Administration, works the security line with Blue, an explosives-sniffing dog at Reagan National Airport. (Jahi Chikwendiu/The Washington Post)

The canines’ job is twofold. They seek out bomb-making materials on moving targets (fed-speak for “people”), a gotcha that could require further investigation by TSA officials. They also help clear passengers for PreCheck, the TSA program for low-risk travelers.

“We have cut back on general, random real-time threat assessment,” said Timberlake, referring to the previously arbitrary selection of passengers for the fast lane. “These dogs are helping people get expedited screening.”

The dogs typically work the line during heavy travel days and times, such as the winter holiday period, and punch the clock for eight-hour shifts. To keep them on their noses, the handlers test the canines’ skills several times a week. They hide suspicious substances in trash cans, wheelchairs, prosthetic limbs and all manner of bags as well as under several layers of clothing. They also place the dangerous matter on civilian decoys.

“They’re finding stuff all the time,” said Timberlake, who wore a black shirt with a TSA K-9 logo, “so we know they’re working and not just looking cute.”

Human participation in the ongoing canine training program is open to all federal employees — plus a few invited guests — who have a free morning or afternoon and no fear of dogs or hazardous materials.

I fit the profile. So for several hours, I played the wily fox in an airport-wide hunt led by GI Dogs.

Suiting up

The agency held the how-to-be-a-pretend-bad-guy lesson in a cramped, windowless room in the old wing of the airport. Before Timberlake suited me up, he reviewed some rules about the substance I’d be carrying.

“Please don’t eat it or stick it in your eye,” he cautioned, “because they are chemicals.”

He also explained the three variables — heat, friction, shaking — that could activate the element. I promised to stay 50 feet away from open flames, avoid fuse boxes and refrain from twitching. Then I signed my name to seal the agreement.

For security reasons, Timberlake could not specify the type of substance or amount used in the tests, but he would say that the agency samples dozens of explosives, including ones involved in recent terrorist attacks and attempts. For reassurance, however, he said that my chance of blowing up was nil: “You are wearing a fraction of what an actual device would be.”

He dropped the mystery block into a pair of nude pantyhose, which I tied around my waist like a leggy fanny pack. Although the dogs weren’t critiquing my outfit, I threw on a jacket to avoid alarming other passengers.

Rriverso leads his handler, Douglas Timberlake, to the author, who is wearing a suspicious substance as part of the TSA’s ongoing training of the working dogs. (Jahi Chikwendiu/The Washington Post)

En route to Terminal B, Timberlake explained how our sense of smell differs from a dog’s. If we pass a restaurant, for example, we can pick up the scent of a pizza. A pooch, meanwhile, can tease out the individual ingredients on the pie: the peppers, pepperoni, tomatoes, mozzarella and sprinkle of Parmesan.

“They are smelling on a molecular level,” he said. “They can detect parts per billion.”

Before the outing, I had imagined a muscular guard dog with razor-sharp teeth tackling me like a rabid linebacker. However, Timberlake told me, the K-9 team is filled with “floppy-eared dogs that don’t intimidate,” such as golden retrievers, German shorthaired pointers, vizslas and Labradors — breeds often found with Frisbees or sticks in their mouths. The four canines at DCA, for example, are all Labradors. Blue, Rufus and Kkirby are as black as licorice; Rriverso is butterscotch yellow. Other personal details: Blue served in Afghanistan, Rriverso is a graduate of the TSA’s first class in this field, and the two dogs with double letters were named after victims of 9/11. (One hint that they aren’t your childhood snuggle buddy: the “Do Not Pet” sashes they wear.)

All the canines attend a rigorous 12-week course at Lackland Air Force Base in San Antonio, where they learn to fix on primary scents and ignore secondary odors. The dogs communicate their discoveries through passive response. They alert the handler of a possible suspect by approaching the person and sitting down or gazing at their master for approval — and the subsequent reward of a calorie-free treat.

“You can see that drive to work, find the explosive and get their toy,” said Mike Gapinski, section chief of canine operations.

During our stroll through the airport, I noted the fragrances that could possibly tempt a dog’s olfactory system, such as the wafting scent of Dunkin’ Donuts pastries and coffee and the bouquet of Milk-Bone biscuits and fur that I wore after a pup-sitting stint. Around me, dozens of people expelled their own plume of smells.

For our initial exercise, I entered the gate area first, so that I could spritz the air with eau de explosives. Blue would enter several minutes later.

“You’re leaving a trail behind,” Timberlake said. “You cannot stop the vaporization process.”

For the demo, the animal would pick up the scent drifting on the air current and follow the clues. Variables such as vents, air conditioning and barometric pressure can push scents around, obscuring their source. But if all went well, the dog would lock onto the essential odor and track me down.

Blue’s clues

I set out solo, blending in with other travelers waiting for their flights. I passed a deli with an open cooler stocked with meat sandwiches. A rack of snacks stood within easy licking distance of a dog’s tongue. At the end of the terminal, I turned around and noticed Blue sniffing around bags of chips. I passed him nonchalantly — nothing to smell here. A few steps later, I was busted.

Blue enjoys his reward for sniffing out explosives material on a moving target. (Jahi Chikwendiu/The Washington Post)

If this had been a real scenario, two behavior detection officers accompanying the canine and the handler would help assess the risk. Many finds are innocent. For instance, the dogs might stumble upon an armed air marshal, a traveler on medication containing a sensitive substance or a sportsman dusted with gun powder residue from a recent foray at the range. Big takedowns are rare.

“No finds yesterday,” said Joe Havens, Blue’s partner. “It was a boring day.”

For the next test, I grabbed a corner chair next to a dozing man. The block of explosives rested against the back of the seat. I saw Timberlake and Rriverso ambling down the hallway, the dog’s nose swinging through the air like a windsock. The Labrador veered left and quickened his pace up the aisle dividing the seat rows. I heard his excited breaths and suddenly felt a nose against my back.

“He’s playing the most fun game of hide-and-seek in the world,” Timberlake said.

But I had saturated the area with the smell of the material, which heightened the challenge. Rriverso had to work harder to isolate the carrier. He inspected the walls and a pallet stacked with boxes. His nose was set on hyper-alert.

“He has to use deductive reasoning,” said Timberlake. “There is no piece of equipment or technology that can problem-solve like he can.”

While Rriverso inspected the area by the cafe, I continued onward and wondered: Would I be the decoy who got away? I was strolling alongside a band of windows overlooking the tarmac when I heard the pitter-
patter of dog paws behind me. Game over.

“I’m pretty proud of him,” a beaming Timberlake said.

Timberlake and Rriverso wait to inspect passengers during their morning shift at Reagan National Airport. (Jahi Chikwendiu/The Washington Post)

The dogs patrol all sections of the airport, including the secured areas (to catch insider scofflaws). Rufus, the youngest pup in the pack, was covering the security line. A sign notified passengers that K-9s were on the job. The 4-year-old stood inside a long rectangle cordoned off by ropes. I approached the entrance at the same time as a hippie-ish guy carrying a backpack. My residue floated onto his pant leg. Rufus gravitated toward his ankles before discovering that he was one person off.

The dogs had started their workday at 6:30 a.m. and were ready for a break at noon. I watched Rufus disappear past security, his eyes fixed on the ball in his supervisor’s hand. I asked Timberlake about Rriverso’s whereabouts.

“He’s napping,” he said. “That lazy bum.”

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