How reliable is 911 during a service outage?

CHICAGO (WLS) -- Police, 911 officials and even Sprint all say your phone should dial 911 on the "strongest signal available" regardless of your provider - but that doesn't mean you can always count on calling 911 from your cell phone.

One man found that out during the recent service outage - and he was worried because of his daughter's medical condition.

Eighteen-month-old Mina Beling has a medical condition that can cause seizures, and could even stop her from breathing if her body reaches a high temperature. So her father, Mike Beling, tested the 911 service when he heard about the Sprint service outage on Wednesday night.

"On speaker phone I dialed 911 and the screen changed to show a picture of a siren default image and there was nothing," he said.

Beling was on the train home at the time so he was thinking of his wife and daughter at home in Wilmette with only Sprint service and no landline.

He says called Sprint from his AT&T work cell phone to report the issue.

"I'm glad nothing happened, everything was fine, my wife was in populated areas at all times, but just the afterthought is disconcerting a little," he said.

We informed Sprint about Beling's concern and a spokesperson responded:

"We are still investigating and analyzing the root cause of the temporary outage."

But what about 911 - should you count on getting through on your cell phone no matter what? Not necessarily.

However, the FCC's basic 911 rules require wireless service providers to transmit all 911 calls to a public safety answering point, regardless of whether the caller subscribes to the provider's service or not. Which means an inactivated phone should still dial 911.

Rules don't address service outages, but according to the FCC, 911 calls should roll over to a compatible network - if there is one.

A Sprint spokesperson also said:

"FCC rules require wireless devices to seek the 'strongest signal' for 9-1-1 calls, regardless of network provider, and also require carriers to carry 'all calls' from 9-1-1, regardless of carrier or even initialization of service."

But as Beling found out, that's no guarantee.

"So your belief is that 911 is always there for you tried and true," Beling said.

That Sprint outage on Wednesday lasted just a little over two hours and did not affect 4G data service.

Emergency management experts tell the I-Team that consumers should have different cell phone carriers in each household in case something happens - you may also want to consider bringing back that landline.