Prime Minister Stephen Harper announced support to put Automated External Defibrillators in community hockey arenas across the country on Thursday but the AEDs need to be registered so emergency crews know where they are.

Many places, arenas, office buildings, even some stores have AEDs but not everyone knows where they are located because they aren't registered.

“We know that there are roughly five to six thousand devices in the province, we know of roughly 2000, 2000 and change. We have a registry that we’ve developed. An online registry where we can track and monitor where the devices are and who’s maintaining them and link that into our 911 dispatch,” said John Hein from EMS.

Hein says there are a lot of devices out there that they are unaware of.

“The two most common problems is a dead battery or missing parts,” said Hein. “So the registry is to try and preempt that. To send them an email notification two months before the expiry date and also going and checking that device for a regular maintenance cycle,” said Hein.

A year ago, John Lester was playing hockey when he had collapsed on the bench and his heart stopped.

Lester survived thanks to quick thinking teammates and a rink staff member who knew there was an AED at the rink.

If he hadn't been there, the 911 operator would have known but that's only because the AED was registered.

EMS says there are three steps in the chain of survival; recognize the emergency and call 911, start CPR and then use an AED to correct the hearts rhythm.

“Time matters here. Every minute that a person does not have a pulse their chances of survival drops by 10 percent, so after five minutes, 50 percent chance of survival, 10 minutes, almost zero chance of survivial,” said Hein.

AEDs today are virtually fool proof and will only emit a charge if its micro-processor recognizes one of two fatal rhythms.

To register an AED with Emergency Medical Services, visit the Heart Safe Community website.