Metrolink sought to prepare Southern California riders for that very possibility on Thursday, engaging in a drill that demonstrated how trains would react in the event of an earthquake.
The trains didn't actually shake or sway in this exercise as they might during a real earthquake. But they did slow down in the same way they would at the first sign of an actual temblor.
The demonstration was part of The Great Shakeout, an annual preparedness exercise to make sure Californians - and millions of people worldwide - are ready for earthquakes.
A Metrolink spokesperson explained that their trains are equipped with technology that gives them an early warning about earthquakes and automatically slows the engine.
Technology developed by the U.S. Geological Survey called Shake Alert provides users with an instant heads-up as soon as a moderate earthquake in their area begins - with the alert ideally reaching them before the seismic waves do.
Metrolink has also installed Positive Train Control technology, which is designed to automatically slow trains down in the event of a possible collision or, in this case, during an earthquake.
The goal is to improve safety for all passengers.
"That's ultimately what we're trying to accomplish - make certain that every rider on every train is safe, from the time they leave their home to the time they arrive at their destination," said Metrolink spokesman Scott Johnson. "But certainly while they're on board a Metrolink train."
For more tips on earthquake preparedness, see ABC7's guide at Prepare SoCal.
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