AT&T Mobility must pay a $5.25 million fine to the FCC and adhere to a compliance plan designed help ensure that 911 calls are completed as part of a settlement to close the investigation into two 911 outages that the agency described as “preventable” and “unacceptable,” the FCC announced yesterday.

The settlement addresses two 911 service outages that impacted AT&T’s voice-over-LTE (VoLTE) network last year—a five-hour outage on March 8, 2017, and a 47-minute outage on May 1, 2017, that resulted in more than 15,000 failed 911 calls, according to the FCC consent decree outlining the settlement terms.

“Both of these ‘sunny day’ outages resulted from planned network changes that inadvertently interfered with the routing of 911 calls by AT&T Mobility,” according to the FCC consent decree.

“Together, the outages knocked out 911 service for almost six hours to millions of AT&T customers across the nation on its VoLTE network. With respect to the March 8, 2017, outage, AT&T Mobility and its subcontractors attempted to notify all affected public-safety answering points (“PSAPs”) through a variety of means, but this process took four-and-a-half hours to complete, and some PSAPs characterized the notifications as unclear or incomplete or stated they received no notification at all.”

AT&T agreed with the FCC’s assessment regarding the cause of the outage.

“Providing access to emergency 911 services is critically important, and to that end, we cooperated with the FCC in their review,” an AT&T spokesperson said in a prepared statement provided to IWCE’s Urgent Communications. “These events resulted from planned network changes that inadvertently interfered with the routing of 911 calls. We’ve taken steps to prevent this from happening again.”

In a press release, the FCC stated that “such preventable outages are unacceptable,” noting that FCC rules require wireless carriers to transmit all 911 calls and inform all PSAPs of any 911 outage that lasts at least 30 minutes. After the March 2017 outage, FCC Chairman Ajit Pai called for an investigation into what happened. The FCC’s Public Safety and Homeland Security Bureau conducting the initial investigation and submitting a report, and the FCC Enforcement Bureau conducted a separate investigation that was closed with yesterday’s settlement announcement.

Under the terms of the settlement, AT&T Mobility must pay a $5.25 million fine and implement changes that are designed to reduce the possibility of future 911 outages.

“AT&T Mobility … will implement a compliance plan to adopt proactive risk-management principles designed to reduce the likelihood and impact of future 911 outages, ensure reliable 911 call completion, and enable the provision of timely 911 outage notification to PSAPs,” according to the consent decree. “Additionally, AT&T Mobility will file regular compliance reports with the [FCC Enforcement] Bureau until the termination of the consent decree.”

During the March 8, 2017 outage, 911 calls from 12,600 unique users failed, and 2,600 additional 911 calls failed during the May 1, 2017 outage, according to the consent decree.

“Such preventable outages are unacceptable,” according to the FCC press release. “Robust and reliable 911 service is a national priority, as repeatedly expressed by both Congress and the commission. Carriers have a responsibility to both prevent outages and, if they do take place, quickly inform the commission and affected 911 call centers.”

During the past two years, AT&T has taken significant steps to become a more integral part of public-safety communications in the future. AT&T was selected in March 2017 as FirstNet’s contractor to build and maintain the nationwide public-safety broadband network (NPSBN). In addition, at least three states—Kansas, Virginia and North Carolina—have selected AT&T to build ESInets that are designed to provide the IP network foundation that is a key component to an eventual migration to NG911.