At home, we consider them man's best friend.  

But on the home front, bomb-sniffing canines are essential in detecting explosives and helping fight the war on terrorism.

We traveled down to Reynoldsburg, Ohio, just outside of Columbus, where canines from several states went through rigorous training to see if their noses could pass the sniff test.

On this particular day at the headquarters of the Ohio State Fire Marshal's Office, Labrador Retrievers had the run of the place.

That's because it was the Annual Recertification of Mid-Western Canine Teams for the ATF and the U.S. Marshals.

Opelika, a four-legged Special Agent with the ATF, made a run past us and she was clearly on a mission.

Her handler David McMullen, of the Bureau of Alcohol, Tobacco, and Firearms Columbus Division, is giving her steady commands as she uses her keen sense of smell to sniff out danger by examining one object at a time.

"She's definitely the talent in the show.  I'm basically directing her to find it.  Her nose is incredible.  She can actually detect over 19,000 explosive odors," McMullen said.

McMullen goes on to say "Ope", for short, clearly, loves her job.

"We can be at a shooting or homicide, a very serious event, but to her, she's really playing hide and seek.  So she's excited. She wants to work and she wants to get rewarded to find food," McMullen said.

Only the best of these explosive detective canines will be on the front lines to detect potential dangers at a time when the nation is on alert because of terrorism and other acts of violence.

One major benefit to these specially trained canines, they're mobile.

Raphael Martinez, Branch Chief of the ATF National Canine Division, said, "It's very critical because a canine cuts down the search time tremendously.  You have people going in and if you have a bomb threat and you've got to search a large building it takes people an enormous amount of time. We can just bring a dog in and he can walk through the room and sniff everything and he can be done in half the time."

These bomb sniffing dogs have to be recertified every single year, and most of them can only work as an explosive detection canine for nine years.  After that many go on just to enjoy everyday life as the family pet.

But that's not the case for Debbie who wagged her tail, looked at her handler, ATF Special Agent Jake Williams of St. Louis, and even whined from time to time as she anxiously waited to take her turn at the Odor Recognition Test.

"I think the Labrador Retriever has it in them. They want to please their handler, they want to please their owner, and it's a food reward system.  So these dogs work to eat," Williams said.

A canine really digging her nose into detect explosive materials that may not only be in the form of bombs but bullets and guns.

It's critical work that can help solve a crime or prevent one.

"She's a very high drive dog. She just turned four-years-old, loves to work, tons of energy.  It's never a problem getting her to do work that she loves to do," Williams said.

The canines are trained never to paw or become aggressive if they detect a possible target because it could be potentially explosive.

But when their breathing becomes heavy, and they sit down that's the final indicator that signals their handler about what they've found.

"She's actually been able to find large amounts of firearms coming from facilities and big gun manufacturers from outside the trucks before she even gets inside the trailer.  So it really makes you feel good when they do something remarkable like that," Williams said.