How important is it that telephone companies provide constant access to 9-1-1 service? Americans make an average of more than 27,000 of these emergency calls an hour, so when a nationwide wireless provider is unable to connect its users to 9-1-1 for even a few hours, they can be on the hook for millions of dollars.

The Federal Communication Commission has announced a $17.5 million settlement [PDF] with T-Mobile following an investigation into a pair of nationwide 9-1-1 service outages on the wireless network.

Both outages occurred on the same day, Aug. 8, 2014, and left T-Mobile users unable to connect to 9-1-1 calls for a total of around three hours.

The FCC’s Enforcement Bureau claims that T-Mobile failed to provide the required timely notification of the outages to all affected 9-1-1 call centers. Additionally, the Commission alleged that the wireless company could have prevented the outage if it had implemented appropriate safeguards in its 9-1-1 network architecture.

In addition to the $17.5 million fine, T-Mobile has agreed to implement a compliance program to identify risks to its 9-1-1 system and protect against these risks.

This is the FCC’s largest fine assessed to a carrier in connection with a 9-1-1 outage and it is the fourth major enforcement action involving 9-1-1 outages this year.

The three other settlements all involved a April 2014 multi-state, multi-provider outage that left around 11 million people without access to 9-1-1.

First, Verizon agreed to pay $3.4 million for its part in failing to prevent that outage. Then in April, the FCC reached a $16 million settlement with CenturyLink and a $1.4 million settlement with Intrado Communications to close the book on this outage.

“The Commission has no higher priority than ensuring the reliability and resilience of our nation’s communications networks so that consumers can reach public safety in their time of need,” said FCC Chairman Tom Wheeler in a statement. “Communications providers that do not take necessary steps to ensure that Americans can call 9-1-1 will be held to account.”

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