After an earthquake, how long can trapped people survive?

NEW YORK (AP) — For those trapped in rubble after an earthquake, survival depends on many factors, including weather and access to water and air.

If their injuries aren't too severe, victims can survive for a week or more, assuming the weather isn't too hot or cold, experts say.

Two days after a powerful deadly earthquake struck western Colombia, rescue teams are racing against the clock to search for survivors.

Most rescues happen in the 24 hours after a disaster. The chances of survival drop with each day after that, experts say. Most victims are badly injured or buried by falling stones or other debris.

After the 2011 earthquake and tsunami in Japan, a teenager and his 80-year-old grandmother were found alive after nine days trapped in their flattened home. And the year before, a 16-year-old Haitian girl was rescued from earthquake rubble in Port-au-Prince after 15 days.

Trapped victims are more likely to survive if they are in a debris-free pocket that prevents major injury while they await rescue, like under a sturdy desk, said geophysicist Victor Tsai from Brown University. Experts call this a survivable void space.

If fire, smoke or hazardous chemicals were released as a result of the building collapse, they may decrease a person's survival odds, said emergency response expert Dr. Joseph Barbera at George Washington University.

Beyond that, having air to breathe and water to drink are crucial as the days go on.

“You could survive a while without food,” Barbera said. “You could survive less without water.”

Temperatures where someone is trapped may affect survival, and temperatures outside the rubble can affect rescue missions.

In Colombia, where governments across Latin America have offered help, authorities have said most of the earthquake deaths occurred in the cities of Cali, Pereira, Manizales and Quibdo, but there is less information about rural areas.

There have been signs of hope, including a 32-year-old woman who was pulled from a collapsed building in Pereira after being trapped for 36 hours.

It can be important for survivors to receive vital medical care before they are removed from the rubble, Barbera said. If not, the buildup of toxins from crushed muscles could make them go into shock after they are rescued.

The best practices for survival during an earthquake depend on where you are in the world. Building codes in regions with active fault lines are often designed to withstand earthquakes, but that doesn't hold true everywhere.

In many countries, including the United States, the best practices are to drop, seek cover and hang on unless you are close to a building exit. Seek shelter under a heavy table or near sturdy furniture that may yield a survivable pocket if the roof collapses. Cover your face with cloth or a mask to protect from dust and debris.

If you are trapped in the rubble after an earthquake, save your energy and don't overexert. Ration food and water, listen for rescue calls and search for something near you to make noise. If you have a phone with you, conserve its battery and try for help in short spurts each day.

The Associated Press Health and Science Department receives support from the Howard Hughes Medical Institute’s Science and Educational Media Group and the Robert Wood Johnson Foundation. The AP is solely responsible for all content.