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How dispatch tech can find 911 callers

The shift from landlines to mobile lines has been a nightmare for locating 911 callers; technology is starting to offer up solutions


No matter how you look at it, a 911 call is a search-and-rescue task. The caller must be found and the service provided, whether it comes from police, fire or EMS.

The ability for telecommunicators in a Public Safety Answering Point to complete that task has been diminished greatly because the vast majority of 911 calls are no longer placed from a landline telephone.

The national 911 system in the United States has grown greatly in coverage and capability since its introduction over 50 years ago. One of its greatest advancements was the development of technology — in cooperation with telephone service providers at the time — that provided the caller’s telephone number (Automatic Number Indicator) and the physical location of where the call was coming from (Automatic Location Indicator).

Advances like wireless devices, text messaging and Voice Over Internet Protocol communications have had an adverse effect on the ANI/ALI look-up process. That’s because first generation ANI/ALI technology was designed to allow the PSAP’s system to access customer database files provided by hard-line telephone service providers, that is, Ma Bell and the Baby Bells.

This worked great when every home and business had a landline telephone and the number of telephone service providers was relatively small.

The 2014 National 911 Progress Report from said that “70 percent of consumers are using cellular phones to make calls to 911, compared to 25 percent of consumers using wire-line phones.”

Improving wireless 911 rules
The Federal Communications Commission adopted rules to improve the reliability of wireless 911 — or E911 — services and the accuracy of the location information transmitted with a wireless 911 call. This consists of two phases

Phase I E911 rules required wireless service providers to provide the PSAP with the telephone number of the originator of a wireless 911 call and the location of the cell site or base station transmitting the call.

Phase II E911 rules require wireless service providers to provide more precise location information to PSAPs — specifically, the caller’s latitude and longitude. This information must be accurate to within 50 to 300 meters depending upon the type of location technology used.

Back when cell phones were new, the 911 system could only map which tower had relayed a given call. Due to the growth of GPS in recent years, the system has gotten much better at locating cell phone callers.

More recently, wireless carriers are required to comply with the FCC’s location accuracy rules at either a county-based or PSAP-based geographic level. The new standards apply to outdoor measurements only, as indoor use poses unique obstacles.

But this technology still lags behind commercial apps such as Google Maps and Uber that seem to know just where your phone is located at any time. So why doesn’t the 911 system?

Next Generation 911
There is a new generation of technologies that makes the current 911 system seem like a Ford Model T. Next Generation 911 (NG-911) creates a faster and more flexible, resilient and scalable system that will enable PSAPs to keep up with communication technology used by the public.

In a New York Times op-ed piece, “The 911 System Isn’t Ready for the iPhone Era,” the chairman of the FCC, Tom Wheeler, wrote:

“The nation’s 911 call centers need to upgrade to NG-911. NG-911 links 911 call centers to the latest Internet protocol-based networks, uses mapping databases and software to route calls and pinpoint the real-time location of 911 callers, and supports voice, text, data and video communication.”

So why doesn’t the FCC just do that — require PSAPs to upgrade to NG-911? The FCC regulates the wireless carriers that the public uses to call 911, but it does not regulate the PSAPs. Control and funding of those call centers lie at the local and state levels.

The FCC can, and has, set new rules for the carriers to improve cell phone location accuracy in the next few years. But it cannot, say, set a timeline for technology upgrades by PSAPs.

Nationwide, there are more than 6,000 PSAPs along with a complicated network infrastructure to deliver the cell phone calls and try to locate them to within 50 meters.

Vendors for PSAP controllers (the technology at the heart of a PSAPs system for processing 911 calls) like Solacom, Informer Computer Systems, and VPI have NG-911 controllers available. These NG-911-compliant controllers are designed to support both legacy and NG-911 calls and new types of requests for assistance, such as text to 911, as they become defined and available.

U.S. National Grid
Far too many people have no awareness of their present location or the ability to figure it out fast, especially in an emergency. When calling 911, a priority question the call taker will ask is about present location.

The U.S. National Grid provides another option for PSAPs using existing technology. It uses the caller’s device’s GPS to generate the USNG coordinates.

Usable data is just 8 to 13 characters and is easy to read and remember. The full coordinate identifies the user’s position to within 10 meters — that’s the size of about two parking spaces.

Once a USNG coordinate is determined, it can be viewed on gridded paper or electronic map, entered into numerous smart phone apps, entered into a PSAP’s computer-aided dispatch software or entered into various free web tools such as GMAP4 or Mission Manager.

Here are the top five advantages of a PSAP using the USNG.

  • It is easy to use for both the user and the PSAP.
  • It is the national standard.
  • It is the subject of FEMA Directive 092-5, Use of The United States National Grid.
  • It is a required data element in NFPA 950, Standard for Data Development and Exchange for the Fire Service.
  • USNG has been the land search and rescue coordinate system since 2011.

Message for wireless phones users
This seems to be a really good tool, but one that nobody knows about. PSAPs, fire departments and other public safety agencies should take the following information and create a public safety messages that is repeatedly communicated to their communities.

After a wireless phone user opens in their Internet browser for the first time, they can then use the app offline. The app uses a coding technique that loads a copy of the entire app into the browser’s permanent memory. This automatically happens the first time the user opens the app.

But, how does it work off-line? If the user goes to a cell dead zone, turns the phone on, opens the same browser and enters, the app will load from the browser’s permanent memory and display the user’s current location.

The short name for this webpage coding technique is “manifest,” and it is supported by all modern browsers. So just like you can go to an app store and download and install a native app, you can also download and install a browser app as long as the browser app uses the manifest coding technique.

The browser’s permanent manifest memory is not the same thing as the browser’s cache, which you can clear on a desktop or laptop computer. The only way for a typical user to clear the browser’s permanent manifest memory on a mobile device is to do a factory reset.

The obvious use for is for 911 callers that are location challenged. In very little time, a call-taker could ask if the caller had a smart phone and also ask them to open in their browser.

In the end, this improved ability to search out the caller will speed the ability to provide rescue services.

Battalion Chief Robert Avsec (ret.) served with the Chesterfield (Virginia) Fire & EMS Department for 26 years. He was an instructor for fire, EMS and hazardous materials courses at the local, state and federal levels, which included more than 10 years with the National Fire Academy. Chief Avsec earned his bachelor’s degree from the University of Cincinnati and his master’s degree in executive fire service leadership from Grand Canyon University. He is a 2001 graduate of the National Fire Academy’s EFO Program. Beyond his writing for and, Avsec authors the blog Talking “Shop” 4 Fire & EMS and has published his first book, “Successful Transformational Change in a Fire and EMS Department: How a Focused Team Created a Revenue Recovery Program in Six Months – From Scratch.” Connect with Avsec on LinkedIn or via email.