Flynn the dog does a lot to help out his 17-year-old human, Hailey Ashmore: He can open and close doors, fetch her parents and, most importantly, alert her to oncoming seizures.

Hailey has had Flynn since November 2014, when the Australian shepherd puppy began his training with her as a medical alert dog. But when Flynn was only 7 months old, a stranger accidentally put Hailey in harm's way by stopping to pet Flynn — and the incident illustrates exactly why working dogs should never be pet or played with while they're working.

Hailey Ashmore

Hailey was visiting her dad at work when someone began petting Flynn like he was just a regular pup. "I immediately told him to stop," Hailey told The Dodo. But in just a moment of distraction Flynn had missed a crucial opportunity to warn Hailey about an oncoming seizure. When he did warn her, it was too late.

"I thought I had 10 minutes to get safe, take medication and call somebody for help," Hailey told The Dodo. "Unfortunately, I didn't and ended up getting a nasty rug burn."

Hailey Ashmore

"Since Flynn was only about 7 months at the time of the accident, he was, and still is, learning to ignore people petting him," Hailey explained. "We understand our dogs are super cute, but they are really important for our safety and health."

"The dog is part of a team," Jessica Reiss, of Canine Companions for Independence (CCI) told The Dodo. "It becomes almost an extension of that person, just like someone's wheelchair … besides the fact that the dog is part of who you are, that touching can distract the dog from what they need to do."

CCI is a nonprofit that trains assistance dogs, including companion dogs and service dogs, and then matches them to people with disabilities. CCI does not train medical alert dogs like Flynn.

Hailey Ashmore

Reiss explained that assistance dogs are trained to go from "being on to off in a few seconds," from hanging out with a chew toy to helping their human in the blink of an eye. When strangers stop to play with assistance dogs, they can interfere with their work.

"They're not a piece of equipment," Reiss said. "They can be distracted."

Hailey's story illustrates just how important service animals are for their humans — and why their vests shouldn't be ignored. Dogs like Flynn provide crucial medical assistance, and while they're working, they need to be 100 percent focused.

Hailey sums it up this way: "If you wouldn't do it to a wheelchair, please don't do it to our dogs."