You never know when or where huge natural disasters will strike.
The same could be said of personal disasters -- like a critical medical emergency.

"I started to feel light-headed in a weird way, and I was queasy at the same time," said Iolani teacher Peter Greenhill, who passed out and went into cardiac arrest during a break in a school basketball game earlier this year.

"It was freak electrical occurences that made the heart beat really fast and erratically. The heart just wants to shut down, so it stops," said Grenhill.

But luckily, a co-worker knew what to do to keep him alive.

"My life had been saved by defibrillator and CPR while I was unconscious," said Greenhill.

Other Hawaii heroes have rushed into a burning building to save a life, or helped a choking woman by using the heimlich maneuver.

"A woman started choking on a piece of steak, she was turning purple. But once the obstruction was out, she started to breath and the color returned. So it was a huge sigh of relief, because then you knew she was going to be fine," said Billy Newell, a U.S. Navy Ensign.

More than a dozen heroes were honored at a Saturday ceremony in Waikiki, for knowing what to do during an emergency and then doing it. The training is something the American Red Cross has been teaching for years.
 
"Everyone should know how to do CPR. You'd feel bad if someone dropped in front of you and you didn't know what to do. Well, you can! You can become a lifesaver as well," said Coralie Matayoshi, the C.E.O of the American Red Cross Hawaii Chapter.

Greenhill's cardiac arrest has been life changing.
The english teacher at Iolani School now also goes around teaching the importance of learning CPR and knowing how to use a automated external defibrillator.