FCC Deals “Major Setback” to 9-1-1 Location Accuracy

The Federal Communications Commission (FCC) on Friday adopted new rules designed to improve location accuracy for wireless 9-1-1 calls in multi-story buildings.

The Order adopts a vertical — or “z-axis” — location accuracy metric of ±3 meters relative to the handset for 80% of indoor wireless 9-1-1 calls. According to the FCC, “This accuracy metric— within three meters above or below the phone—will more accurately identify the floor level for most 9-1-1 calls and is achievable, keeping the deployment of vertical location information to public safety officials on schedule.”

Current regulations require wireless carriers to provide horizontal location data (usually “x/y” GPS coordinates), which allows a 9-1-1 center to plot a caller’s approximate location. The new rules require wireless carriers to provide height-above-ellipsoid (HAE) data in order to identify a caller’s vertical location (“z-axis”).

But according to the Association of Public-Safety Communications Officials (APCO) International, “the rules will not only fail to produce meaningful improvements, but the FCC will also let wireless carriers continue to avoid pursuing much better options for 9-1-1 location accuracy.”

APCO is concerned that HAE estimates will not provide actionable information for First Responders. Instead, APCO says wireless carriers should be required to provide the floor that the caller is believed to be on in the particular building from which the call is originating.

According to APCO:

“Height Above Ellipsoid” (HAE) is a raw technical format for altitude. While trying to save a life, the 9-1-1 dispatcher would receive something like “101 Main Street; 76 meters, +/- 3 meters HAE” instead of “101 Main Street, 7th floor” or “101 Main Street, Apt. 702.” When someone’s life is at stake, there is no question about which kind of information would be more effective.

The largest 9-1-1 centers in the country have said that even they don’t have the resources to turn “HAE” data into actionable information because it would require significant time and money to create and maintain 3D maps for the millions of buildings across the country, and then specialized software to translate the HAE readings onto the maps.

The FCC assumes that responders in the field – police, fire, EMS – would have devices and apps that provide HAE measurements that could be matched to the caller’s. This, too, 9-1-1 experts have said is unacceptable. It adds extra time to the response while responders go up and down the stairs or elevator attempting to match their HAE measurements to the HAE reported to 9-1-1. Plus, the FCC’s rules will only require accuracy of +/- 3 meters (equivalent to 10 feet) for the 9-1-1 caller’s HAE measurement (and only for 80% of calls), and the rules don’t take into account the additional error that could arise from responders’ devices producing their own HAE measurements. Google submitted a letter to the FCC that has a picture that explains this problem well:


FCC Commissioner Jessica Rosenworcel, who voted against the Order, agreed that the height-above-ellipsoid (HAE) format that the carriers must use to deliver vertical-location information is not useful to public safety.

“There is not one 9-1-1 call center today that can take the raw numbers in height above ellipsoid and translate them into actionable dispatchable-location information,” Rosenworcel said during a press conference following the FCC open meeting. “If we acted in this room today like the job is done, then we lied to you. And I’m afraid our decision was dishonest about whether the information is actionable.”

Several public safety organizations praised the new rules. “Getting vertical-location information with 9-1-1 calls within 3-meter accuracy in the near term is more helpful than waiting for all aspects of the dispatchable-location challenge to be resolved,” according to Harold Schaitberger, president of the International Association of Fire Fighters (IAFF). “We cannot let the perfect be the enemy of the good.”

The FCC will continue to accept comments on the Order, improvements to 9-1-1 location accuracy, and alternatives to dispatchable location.

Maryland is accelerating its move toward the deployment of a statewide Next Generation 9-1-1 (NG911) system – which will make public safety both more effective and more responsive by improving wireless caller location, accommodating incoming text/video, and managing crisis-driven call overflows.

The Commission to Advance Next Generation 9-1-1 Across Maryland, a 2018 MACo Legislative Initiative, submitted its 2018 report to the Governor and General Assembly in December of last year. The report included recommendations for the implementation, technology, funding, governance, and ongoing statewide development of NG911.

As a result of the Commission’s work, the Governor in April signed into law SB 339/ HB 397, Public Safety – 9-1-1 Emergency Telephone System (Carl Henn’s Law), a 2019 MACo Legislative Initiative to update state laws, and the 9-1-1 financing system to provide the flexibility and resources needed for the deployment of a statewide NG911 system.

In 2019, the Commission reconvened to further strengthen the 9-1-1 system in Maryland by focusing on key initiatives to ensure a smooth transition to NG911. The Commission will submit its 2019 report in December.

Stay tuned to Conduit Street for more information.

Useful Links

FCC Press Release: FCC Helps First Responders Quickly Locate Wireless 911 Callers

APCO International: FCC on the Verge of a Major Setback to 9-1-1 Location Accuracy