(NEW YORK) -- It's impossible to know when an earthquake will hit, but preparing for one can save your life. That's the purpose behind Thursday's "Great ShakeOut."
The earthquake rehearsal drill will take place across more than a dozen states, as well as in other countries, at 10:18 a.m. in each time zone. More than 14 million people have signed up for the exercise, including more than nine million in California.
Earthquake expert Brian Blake says a simple reminder saves lives.
"That is drop, cover and hold on, which involves getting under a table or desk and staying under there until the shaking stops," he says.
Also, avoid running outside, where falling parts of buildings could cripple or kill, advises Missouri State Emergency Management official Steve Bessemer.
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