Sign up for one of our email newsletters.

A regional 911 dispatch system designed to provide uninterrupted service should individual counties experience an outage did not live up to that promise for several hours Tuesday morning.

A telephone server that provides 911 service to 13 Western Pennsylvania counties failed around 6 a.m., resulting in an outage for 911 services in Westmoreland, Armstrong, Somerset, Indiana, Butler and Cambria counties.

County officials said the issue appeared to be with the phone provider through which the 911 centers are connected.

"There was a glitch somewhere. We don't know where. We're still trying to find out," said Steve Bicehouse, Butler County's emergency services director.

Service in Butler and Somerset was restored about 9 a.m., and Westmoreland and Indiana resumed service about 10 a.m. The outages Tuesday, though brief, caused concern.

"This is unacceptable to us," Bicehouse said. "We can't have this happen again."

Since 2012, more than a dozen counties in Western Pennsylvania — including those affected Tuesday morning — have joined to form Western Pennsylvania County Regional ESInet, or WestCORE.

The aim of the network was to lower costs for each county as well as streamline the emergency dispatch process by replacing outdated equipment and allowing county dispatch centers to use the same computer network.

Doing so, officials said at the time, would allow one county to pick up the 911 calls of another should that county have system problems or failure.

But that didn't happen Tuesday, leaving callers unable to reach first responders via the three-digit emergency number.

"We thought we had a fail safe in place, but it didn't work," said Roland Mertz, director of Westmoreland County's public safety department.

While the system was off-line, emergency dispatchers in Westmoreland and Butler counties fielded calls through a 10-digit telephone number.

"Luckily, the timing was such that we didn't have a large volume of calls," Bicehouse said.

Officials have asked Airbus DS Communications, the company that built the 911 phone switch, and CenturyLink, the phone provider, to pinpoint why the safety valve failed "so it doesn't happen again," said Ron Baustert, Armstrong County's 911 coordinator.

Attempts to reach officials at Airbus and CenturyLink were unsuccessful.

WestCORE includes Allegheny, Butler, Westmoreland, Somerset, Indiana, Armstrong, Fayette, Forest, Greene, Lawrence, Mercer, Cambria and Venango.

"The system's been relatively stable," Bicehouse said. "Today something happened. That's what we're trying to get to the bottom of."

Trib Total Media staff writer Rich Cholodofsky contributed to this report. Guza can be reached at 412-380-8519 or mguza@tribweb.com. Raap can be reached at 412-320-7827 or traap@tribweb.com.