When disaster strikes without warning, why do some die while others survive? A second can make the difference between life and death.
"You are responsible for your life," said Ed Galea, professor at the Universities of Greenwich, Liverpool and Ulster, who has spent the last 25 years analyzing how humans react in emergencies. "If you know what you're doing, you've got a better chance of surviving."
Galea and his team interviewed 300 people who escaped from the attacks on the Twin Towers on 9/11. They made a startling discovery. When the planes hit, only one in 10 people inside the World Trade Center reacted immediately.
"The majority of people took about a maximum of about eight minutes to react to the building being hit! Eight minutes," he said. "Some people even took longer -- 20 minutes, 30 minutes -- to actually disengage from whatever activity they were involved with to start to physically evacuate."
That's normal human behavior, but it's not the most prudent for survival. Galea walked "Nightline" through his tips to survive disasters -- and strategies to weather a plane crash, train crash or sinking ship.
1. Listen to the alarm.
Galea said the most common response to hearing a fire alarm, or any sort of emergency alarm, is to ignore it. People assume that any alarm is a false alarm, or just a drill.
"People don't want to be, or to appear to be weak or to be silly or to be scared," Galea said. "Peer group pressure actually prevents people from being the first to react. And once you've had one person react, other people are likely to follow."
But when escaping disaster, every second counts.
"People need to learn to react immediately [when] an alarm is sounded," he said.
2. Fear fire. It spreads very fast.
In modern life, our fear of fire has dimmed to a dangerous nonchalance.
"People have lost respect and understanding of fire," Galea said, "The only time people come into contact with fire in modern society is perhaps lighting a barbecue."
When a blaze swept through a British department store in 1979, people could smell the fire, could hear the alarm, but since they'd just bought lunch, they stayed to finish eating. The fire killed 10 people -- most of them in the cafeteria. If you weren't out of that building in 30 seconds, you didn't stand a prayer.
In 2003, 100 people died at a Rhode Island nightclub during a fire sparked by a pyrotechnics. "The fire just engulfed the building at such a high rate of speed -- from then on it turned into a nightmare," one survivor said.
Galea built a computer model of that fire and saw how quickly flames and smoke spread. It only took 90 seconds until the entire dance floor and bar area were covered.
3. Have a plan.
Faced with a threat or disaster, some go into superhuman mode -- they are calm and strong and endeavor to save others and themselves. Some simply freeze. It's the "fight or flight" response.
"If you haven't thought about what you might do and prepared, the thing becomes overwhelming and you shut down," Galea said. "You can prepare yourself to react appropriately in emergency situations."
Whether you're boarding a train, a plane, a cruise ship -- or if you're walking into an unfamiliar building, a hotel perhaps, figure out how you would get out in a hurry.
Once you've checked in, Galea says to find out where the nearest exit is and actually walk the route between your room and that exit, counting the number of doors along the way. That way, if the corridor is filled with smoke, you can actually feel your way to safety.
When Galea checks into a hotel, he asks for a room on the sixth floor or below. Why? Most fire ladders can't extend above about six floors.
And you may think it's overkill, but the professor actually walks the fire escape route, checking that there aren't any obstacles in the way -- no piles of dirty laundry or trays of half-eaten room service food.
His golden rule: you don't want to find out there's a problem with your escape route when the fire's already started and your life's already in danger.
In 1996, a hijacked Ethiopian airliner carrying 175 passengers ran out of fuel and crashed into the Indian Ocean. Ninety people were killed. Many of them drowned because they inflated their lifejackets too soon and got stuck inside the sinking fuselage.
Lesson learned: wait to inflate until you're on the outside.
Despite public perception, around 95 percent of those involved in plane crashes in the U.S. emerge alive.
Galea has interviewed more than 2,000 survivors. Since each crash is different, there's no magic or safest seat, in which passengers are most likely to survive. But statistics suggest sitting within six rows of an emergency exit -- preferably, in an aisle seat -- help your chances.
"An aisle seat because ... it's easier to get on your feet and start heading towards an exit," he said. "And just as you would in a hotel, on a plane count the seats to the emergency exit."
This past summer, nine people were killed and more than 70 injured when one Washington, D.C. Metro train plowed into the back of another at the peak of evening rush hour. It was one of the darkest days in Washington Metro history.
What can you do when riding a train to increase your chances of survival?
"Whenever I get on a train I will avoid the front and rear cars," Galea said, since they are most likely to be hit or to hit something. "I will take a seat where my back is facing the direction of travel."
If the train crashes, you will be pushed backwards into the seat, not thrown across the car.
"I hate having lots of luggage in the luggage racks above my head. Because in the event of an accident, the luggage is going to come down," he said.
In 1991, Oceanos, a Greek cruise ship, was hit by a massive storm off the coast of South Africa.
"Everybody was so calm, it was the crew that were not," one survivor said. "The crew were jumping ship first. The crew went first, they were actually fighting the passengers."
The panicked crew abandoned ship and left the passengers to fend for themselves. Amazingly, all 571 passengers were eventually rescued. They survived partially because they kept calm and perhaps because they knew what they were doing.
"Ships are very, very confusing environments," Galea said. "You can't see outside. Often you don't even know is forward and aft, let alone if you're on the port or starboard side of the vessel."
Walking your escape routes, making a note of where you are on the boat, is particularly important if you want to escape before it's too late.