When six-year-old LASD detection dog “Sstack” isn’t enjoying time off at his home in Santa Clarita, he’s patrolling the Metro rail systems throughout L.A. County with K-9 Deputy Amy Raniag, searching for explosives using his carefully trained nose.

Raniag and Sstack — whose double “S” indicates he was named after a 9/11 victim — have been partners for almost four years now, living and working together as a K-9 team for the Los Angeles County Sheriff’s Department’s Transit Policing Bureau.

Sstack with his partner, K-9 Deputy Amy Raniag.

“We start our day at 5 a.m. and we report to the downtown area, where we attend briefing or we just prep for the day,” Raniag told the KHTS Features team at the Newhall Metrolink Station, where the duo boarded and searched several trains throughout the morning. “We deploy out for the majority of the morning while a lot of people are travelling to work and what not, and we just provide this visible deterrence.”

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On a daily basis, Sstack and Raniag board trains and sweep platforms at random Metro stations throughout the county, ready to respond to suspicious packages or threats to the rail system at a moment’s notice.

Raniag noted that a dog’s nose is completely different than a humans, and can easily detect anything from narcotics to explosives to cell phones with the right training.

“Say we walk into a room that just had cookies come out of the oven — you and I walk into that room and we can smell a fresh batch of cookies,” Raniag explained. “(Sstack) walks into the room and he can smell the flour, the sugar, the butter, all the ingredients that went into that cookie to make it.”

Sstack got his start at Lackland Airforce Base in San Antonio, Texas — which Raniag called the “main hub” for military working dogs — at just 10 months old, where he took a series of tests designed to see if a puppy might be well-suited as a working dog.

“They want to make sure that dog has a high drive, that they’re willing to go out and find the toy and bring it back and continue with that game,” Raniag said. “Once they determine that this dog might make it into the program, then they graduate them and they will start introducing whatever training aid it is that they want them to train on.”

In Sstack’s case, he was then introduced to explosives to begin his training as an explosives detection dog.

After successfully completing the next phase of tests and training, Sstack was transferred to San Francisco Airport, where he worked until he was three years old before he was officially assigned to Raniag.

Sstack’s “trademark” crawl.

Though he takes his job as a LASD detection dog very seriously when on duty, Raniag noted that Sstack is still a normal dog with his own unique personality and silly quirks.

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“Sstack is a goofball,” she said with a laugh. “I had an instructor in K-9 school tell me that they try to match the dog’s personality with the handler’s, so to say he’s a goofball just means I’m a goofball. He’s bubbly, he’s energetic, he’s always on the go, so yeah — our personalities match pretty well.”

The pup’s signature quirk is to lay down on his belly, sprawl out his long limbs and then crawl as if he’s swimming, which Raniag noted he is sure to do every single time the pair gets out of the car.

“It’s the silliest thing,” she said. “I don’t know why or how it started, but that’s his trademark.”

Raniag knew she wanted to be a K-9 deputy since participating in the LASD Explorer program at the Lancaster Sheriff’s Station as a young adult, where she had the chance to watch a K-9 demonstration by a Special Forces Bureau deputy.

“I instantly fell in love,” she recalled. “I love dogs, and I thought, ‘If I can be a deputy sheriff and work with dogs, that would be like the ultimate job.’”

A common question Raniag gets from the public is what kind of “fun” explosive devices she and Sstack have found while on duty, and her answer usually surprises them.

“I always report, we haven’t found any and we don’t want to find any,” she said with a chuckle. “Basically we’re out there as a visible deterrent, we’re out there to cut down on response times on what could be a suspicious package that could potentially harm thousands of people… We want to make sure that nothing happens, so we don’t want to find anything.”