In preparation for the ever-looming “Big One,” millions of people across California are expected to “drop, cover and hold on” during staged earthquake drills on Thursday.

In Los Angeles, the drill will take place at 10:17 a.m. at Rosemont Elementary School, where students will act as if they’ve been injured in a quake and emergency crews respond to the scene.

In the drill, which will simulate a major earthquake, firefighters will rescue students -- made up to appear to have quake-related injuries -- while suppressing a building fire on the school grounds, the Great California ShakeOut said in a release.

INTERACTIVE: Map of L.A.'s hidden earthquake dangers


The drill will stage situations that could occur during a large earthquake, such as blocked access, trapped and injured victims, and fire, organizers said. More than 9 million people are registered to participate in drills throughout California.

Before the drill at Rosemont Elementary, Los Angeles Mayor Eric Garcetti is scheduled to speak at an assembly for fourth- and fifth-grade students.

Garcetti is facing a tangle of unforeseen political and legal challenges as he grapples with what action the city should take to identify and reinforce hundreds of old concrete buildings that may be at risk of collapse in a major earthquake.

FULL COVERAGE: California earthquake safety


Responding to a Los Angeles Times report of structurally vulnerable buildings that could expose thousands to injury or death, Garcetti said he was “interested in creative ways of making buildings safer.” But he raised concerns about the city’s potential liability if it publicly identifies structures at risk of failing during violent shaking in a major quake.

“I think it has to be done really carefully, because people can sue us ... for loss of value of their property,” Garcetti said.

ALSO:

Orange County D.A. raids police union law firm, seizes records


Man charged with murder in stabbing death of Long Beach teacher

Suspect got the dry ice for LAX bombs from an aircraft, officials say

Twitter: @aribloomekatz | Facebook

ari.bloomekatz@latimes.com