How TSA dogs are intercepting explosives at Mineta San Jose Airport

SAN JOSE, Calif. (KGO) -- TSA says explosive devices are the greatest threat to aviation, which makes interception a top priority. To that end, the Bay Area's three international airports have teams of bomb sniffing dogs checking passengers and their baggage.

They serve both as a deterrent and as a key way to detect if explosives find their way onto a commercial flight. TSA says these dogs are able to smell not only a fully assembled bomb, but also hundreds of components that are used to make a destructive device.

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Blek is one of several explosives detection canines working at Mineta San Jose International. He's a 5-year-old German shorthaired pointer, who has been working at the airport with his handler Sasha for two years. The dogs and their handlers are matched up by personality, and they undergo a 12-week training at a special program in Texas.

"Some dogs are certified to work up to an hour," said Lorie Dankers, TSA public affairs manager. "Most dogs will 30 to 45 minutes in a shift, and they may work more than one shift per day."

Rhena Quedada and her dog Bank, a 7-year-old black Labrador Retriever, are a team 24 hours a day.

"He kind of doesn't have an off switch," she said. "Once he gets into the truck or he knows we're getting ready for work... that's kind of like one of the qualities you kind of want is that you're always on."

Bank's reward is getting to play with his squeaky toy, a Kong Tail.

The TSA canines provide one more level of security on top of the routine screening and scans that passengers undergo to offer them protection.

"Sometimes they could miss something," said Yisel Cruz, who was seeing off a friend to Germany. "And dogs have like a great sense of smell, so they could capture these types of things that maybe a machine wouldn't."

How good is a dog's sense of smell? TSA explains it this way -- while people smell a pizza, a dog can smell the individual ingredients.

TSA has 320 canine teams nationwide. And they seem to love their dangerous job.

Each of the dogs wears a sign saying "do not pet." They are busy working, but there's a secondary reason for that. They need to sample the air to detect explosives, and people getting too close prevents them from doing their job.