The federal government will investigate an outage inside the CenturyLink telephone company system that left thousands of 911 emergency calls unconnected for hours in at least eight states.

The Federal Communications Commission said the 911 system outage April 9 hit Washington state, Oregon, California, Pennsylvania, Minnesota, Florida, North Carolina and South Carolina.

“Preliminary data submitted to the Federal Communications Commission’s Network Outage Reporting System indicate that in Washington alone, over 4,500 911 calls … did not get through during a six-hour period beginning just after midnight on April 9, 2014,” the agency said.

“Given the large area impacted by this outage, the interdependent communications infrastructure spread across multiple states and providers, and the critical importance of dependable and resilient 911 service throughout the United States, the Public Safety and Homeland Security Bureau is examining the causes, effects and implications of this outage.”

The FCC said an open public comment period will be held.

CenturyLink said in a report weeks after the incident that it had subcontracted with a company called Intrado to route 911 calls through a company facility in Colorado to appropriate dispatch centers.

The system that was supposed to assign each call a number so it could be routed to the appropriate center ran out of available numbers, stopping the calls, CenturyLink and Intrado said.

The Columbian newspaper in Vancouver, Washington, reported Washington state officials, who also are investigating, said CenturyLink has raised the total available numbers so “it is not theoretically possible to exhaust the threshold ranges” again.

However, the 911 outage is a small illustration of what could happen to the nation’s communication systems in the event of an electromagnetic pulse, or EMP, either from a nuclear explosion at altitude above the U.S. or a solar flare.

Read the documentation that’s sparking the worry about the EMP threat, in “A Nation Forsaken.”

An EMP event could result in the deaths of up to nine in 10 people in the United States, according to some experts.

Recently, Peter Vincent Pry, executive director of the congressional advisory Task Force on National and Homeland Security and director of the U.S. Nuclear Strategy Forum, lobbied for the Critical Infrastructure Protection Act, or CIPA.

He said lack of congressional action on the threat is delaying progress to prepare at the state and local levels.

Pry has warned that a natural or nuclear EMP event could black out the national electric grid and communications systems for months or years and collapse all of the other critical infrastructures essential to sustain a modern society and the lives of 310 million Americans.

The critical infrastructures include communications, transportation, banking, finance, food, water and emergency services.

“As the National Planning Scenarios are the basis for all federal, state and local emergency planning, training and resource allocation, an EMP National Planning Scenario would immediately and significantly improve national preparedness for an EMP catastrophe,” he said.

Pry is referring to some 15 National Planning Scenarios maintained by the U.S. Department of Homeland Security, each of which outlines procedures to act in the event of various catastrophes, such as flooding, hurricanes and even terrorism.

However, EMP is not one of the 15 National Planning Scenarios.

“Thousands of emergency planners and first-responders at the federal, state and local level want to protect our nation and their states and communities from EMP threat,” Pry said. “But they are seriously hindered and even prohibited from doing so, because the EMP threat is not among the 15 canonical National Planning Scenarios used by the Department of Homeland Security.”

A Heritage Foundation report concluded damage to the communications system would be much worse from an EMP event than other causes.

The attack, the report said, would cause the “damage to power lines … control systems and commercial computers [that] would likely be permanent due to fused power lines and lost data, which would necessitate replacing the entire electric system in the affected area.”

In the recent outage, KING-TV in Seattle reported that one woman was hospitalized after trying to call 911 multiple times, because she was passing out.

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