Scores of Californians simultaneously dove under desks and tables at late morning Thursday in a massive drill to practice basic earthquake survival skills.
At 10:21 a.m., school children and workers rolled under their desks, city sirens wailed in San Francisco and Bay Area Rapid Transit trains came to a stop for one minute.
Organizers of the "Great California ShakeOut" said nearly 8 million people signed up to participate _ including schools, businesses, churches, community groups, hospitals and emergency responders.
"The risk is real," said Matthew Bettenhausen, secretary of the California Emergency Management Agency, after a portion of the drill at Providence Saint Joseph Medical Center in Burbank. "To not prepare is to be selfish and irresponsible."
Not everything came to stop, however. In Los Angeles, a state Medical Board hearing concerning the license of octuplets mother Nadya Suleman's fertility doctor was interrupted by a public address announcement of the drill, provoking giggles in the room.
The drill, which came about a half hour before a real magnitude-6.9 quake struck Mexico's Gulf of California, is aimed at greatly increasing residents' preparedness and the speed at which the state will recover from future quakes.
Despite California's long history of devastating temblors, many people have never experienced a destructive earthquake. The state's last seismic disaster in a metropolitan area was the 1994 Northridge earthquake.
California also has many residents who weren't educated in the state's schools, where they would have learned what to do during an earthquake.
Bettenhausen urged families to make sure they have enough food and water to last three days after a quake.
"We're going to be overwhelmed. We need individuals to be more prepared," he said.
The annual drill has grown since it began in 2008 as a Southern California regional exercise based on a magnitude-7.8 earthquake on the southern San Andreas Fault, a scenario created by the U.S. Geological Survey's Multi-Hazard Demonstration Project.
In 2009 the drill went statewide in California and New Zealand's west coast also conducted a ShakeOut.
This year the drill expanded to include some residents of Nevada and Guam, and in 2011 there will also be ShakeOuts in British Columbia, Oregon and the central United States.
Associated Press writers Raquel Maria Dillon in Burbank and Shaya Tayefe Mohajer in Los Angeles contributed to this report.