JACKSONVILLE, Fla. -- The Jacksonville Sheriff's Office 911 center gets up to 5,000 calls on any given day.

Of those calls, about 70 percent are made from a cell phone.

But unlike a landline, the address of the caller's exact location doesn't pop up on their screens.

So what happens when you're in an emergency and you can't tell them where you are?

"Sometimes that happens, but were able to use our ally tracker and GPS coordinates, and usually it'll narrow it down to a specific area," Maj. Sharon Elliott said.

But that area isn't traced from the closest area near you, per se.

Rather, it relies on the cell phone tower you're calling from, which can be anywhere within a 125-meter range.

"We can pinpoint it down usually to a specific area, and we send units to the area to try and locate them," Elliott said.

Even though Elliott said the system is fairly accurate, that's not always the case.

But in a business when every second counts, it could be a matter of life and death.

"I know we had an incident where someone called from their cell phone and was in medical distress, and we got to the house next door to them," Elliott said.