
It's one of the ways the TSA sniffs out potential security threats at airports, including Philadelphia International Airport, and it could be right under your nose.
Actually, these TSA explosives detection dogs are more likely at your feet.
"The passenger screening canine program came along to better detect explosives coming to the checkpoint and also to speed up the check point," said TSA K-9 handler Gary Stoerrle.
Stoerrle's partner is Bak, a 5-year-old black Labrador retriever who specializes in air flow detection.
"They are single purpose. They are only for explosive detection, they don't attack. They don't apprehend. No drugs. Their main goal is to go through enough change in behavior for the handler to interpret, and then we decide whether to escalate from there," Stoerrle added.
There are about 1,000 TSA K-9s working in airports across the country.