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Cellphones made it harder for Denver’s 911 call takers to track people down. Finally, that’s starting to change.

The city is urging people to update their phones to make sure they can be tracked by 911 call takers

Inside the Denver 911 Emergency Communications Center. (Jesse Paul, The Colorado Sun)
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Before cellphones became ubiquitous, tracking down people who dialed 911 was one of the easier parts of an emergency-call taker’s hectic job.

Infrastructure built into landlines allowed first responders to know exactly where someone in distress was ringing from, down to the unit in an apartment building. A police officer, fire crew or EMT was dispatched right to their door.

But as Americans ditched the wall-mounted portal to the world and turned to mobile phones, 911 communications centers all over the country — including Denver — face a serious problem: How to reliably determine where emergency calls are coming from when the person on the other end doesn’t know, or can’t say, where they are.

The geolocation technology exists, but until now it’s been mostly in the hands of of people hoping to make a profit: ride-sharing companies trying to get drivers to their fares and smartphone users looking for their friends.

“Most people thought we could already do this,” said Athena Butler, executive director of Denver’s 911 Communications Center. “People are like, ‘I can see where I am on my phone. Why can’t you?’ We’ve had that asked because that technology wasn’t delivered to a 911 center yet. Now that it’s out there and we have the opportunity, we’re using it.”

Athena Butler, director of the Denver 911 Emergency Communications Center, oversees call takers in October. The center was covered in Halloween decorations.(Jesse Paul, The Colorado Sun)

Denver is among the first cities to experiment with a new system that gives dispatchers a more consistently accurate bead on the location of people who call 911 from a mobile device.

It’s not that 911 call takers couldn’t get any information on where people were located before. They could, but sometimes it wouldn’t be spot on and it wasn’t possible to tell whether the location was accurate.

“Sometimes it was exactly where you are, but you would not get that all the time,” Butler said. “Sometimes it’s where the cell tower is located that your call is coming off of — we would get the tower address. It could get exactly, within a half a block, it could get within a football field.”

But a New York-based company, RapidSOS, is helping 911 centers tap into the technology already being used by smartphone apps — like Uber — to track down people in need of emergency help.

It’s called the “NG911 Clearinghouse” and it’s being used in more than 2,000 emergency call centers across the country, including Denver’s. 

Roughly 95 percent of 911 calls received by the Denver 911 Communications Center come from cell phones. That squares with Pew Center research released earlier this year that showed about 95 percent of Americans have a cell phone of some type. Less than half of homes in the U.S. still have a landline.

Denver began testing the system in March, and it was officially launched in May. So far, its accuracy percentage is in the 90s.

Here’s how it works: When a call comes into the Denver 911 Emergency Communications Center, a map with a single dot pops up on the call taker’s screen. That dot represents the older cell phone technology that can be problematic. Then a second dot shows up, plotting the caller’s location using the RapidSOS system.

Sometimes the dots are right on top of each other, but when they aren’t dispatchers can look to the RapisSOS location.

A Colorado Sun reporter was there to see how the system worked one day in October when a 911 call came into Denver’s emergency communications center. The person on the other end of the line was reporting a medical emergency downtown.

“Is he awake? Is he conscious? Is his breathing completely normal? I want you to say ‘now’ every time he takes a breath,” the call taker said.

The first location that popped up was on one side of the street, the second dot was on the other side.

Even that short distance, officials say, can make a life-or-death difference.

A Denver fire truck races to an emergency in October near East 11th Avenue and Lincoln Street. (Jesse Paul, The Colorado Sun)

“It really is great. Whenever it can actually tell us where exactly where people are standing, that’s best,” said Shelly Lesnansky, a manager at the Denver 911 Communications Center. “Imagine if you are police or fire in one of those big rigs and you are trying to find a person on a corner. There’s a lot of corners between here and (wherever the caller might be).”

And seconds count for first responders. The longer they have to search for the person making a 911 call, the more danger the caller faces.

Arapahoe County is also using the RapidSOS system, and Denver officials says Jefferson County’s 911 center is in the process of getting it.

More Colorado agencies are expected to add the system soon.

Smartphone users don’t have to get a specific app to make sure 911 call takers can see their exact location with the RapidSOS system. They simply must make sure their devices are running Android’s 4.0 operating system (released in October 2011) or newer, or Apple’s iOS 12 (released in September) or newer.

Denver and Arapahoe County authorities have been using a public relations campaign to persuade people to make sure their phone operating systems are updated.

Athena Butler, director of the Denver 911 Emergency Communications Center, oversees call takers. (Jesse Paul, The Colorado Sun)

“When it gives people an additional resource that helps in terms of their safety and the only the way we knew that it would work is to update their system, I don’t mind asking that,” Butler said. The RapidSOS system isn’t used to track citizen phones unless someone dials 911. 

“It’s still a choice whether people update their system or not,” Butler said. And she’s definitely still urging the public to take the step. It turns out those nagging software update reminders now might actually be a matter of life or death.

“A lot of times it’s really giving you more of what you’re paying for with these devices,” Butler said. “With this one, it’s helping in terms of your safety.”


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