Despite safeguards, system failure caused 40-minute outage in Vermont's enhanced 911 system

The company that runs the state's 911 emergency telephone system said a 40-minute outage this week was caused by a "double equipment failure" followed by another error that left the system unavailable.

Intrado, of Longmont, Colorado, goes to great lengths to ensure the 911 system has multiple layers of redundancy, its vice president said Thursday in a statement distributed by Vermont's Enhanced 9-1-1 Board, which was established to develop, implement and supervise operation of the system.

"Intrado takes our responsibility to 9-1-1 very seriously and are working closely with the State of Vermont on this issue," Intrado Vice President Steve Lowe said in the statement.

It appears that everyone who called for help during Wednesday's outage was able to reach emergency responders through other numbers, E911 Executive Director David Tucker said. Officials were working to contact everyone who called 911 during the outage but was unable to get through, he said.

"We are disappointed with the performance of our technology vendor, both for the fact that the system failed and also for the time it took to get the callback numbers for those who were not able to get through to 911 during the outage," Tucker said. "911 services are supposed to be available at all times, so an outage of this magnitude, even though the duration was short, is not what we expect from our service partners who have been entrusted to manage this system for Vermont."

Tucker said the state has informed the Federal Communications Commission about what happened to its 911 system.

Vermont's 911 system is enhanced, meaning it's usually able to locate a caller, the Enhanced 9-1-1 Board's website says. To locate callers, it uses a database containing the location of every wired telephone in the state, while cellphones, which aren't in the database, are located through a third-party location service, the site says.

The system was working normally Thursday.