Standing under a doorway during an earthquake is a common mistake. Here's what to do instead.

• A 4.8-magnitude earthquake shook the East Coast Monday, and many people ran for doorways.
• Standing in doorways isn't the safest reaction, and neither is running outside during shaking.

When a 4.8-magnitude earthquake rattled New Jersey, New York, and other East Coast states Friday morning, many people rushed for the nearest doorway.

But standing in a doorway is based on an old earthquake myth that might put you in a risky position.

"That's not something you should do, because usually in a building wherever we have an opening, whether a window or a door, that's a structural weakness in the building," Lingsen Meng, professor in UCLA's Department of Earth, Space, and Planetary Sciences, told Business Insider.

"So you should stay away from the doorway," Meng added.

Another earthquake of similar or greater magnitude could occur in the area in the coming weeks, scientists with the US Geological Survey said in a briefing on Friday. The millions of people on the East Coast should know what to do if that happens.

What to do during an earthquake

"In modern houses, doorways are no stronger than any other part of the house. Doorways do not protect you from the most likely source of injury − falling or flying objects," the US Centers for Disease Control and Prevention says in its guide to earthquake safety.

Nor should you immediately run outside, which is another common myth about safe earthquake response.

Instead, these days the main guidance is to drop where you are, cover your head and neck (ideally by crawling under a sturdy table), and hold on until the shaking stops.

"If there's nothing you can find [to crawl under], stay on the ground and cover your head. Maybe crouch a little bit to have a small footprint," Meng told BI.

If you're inside, stay inside, the CDC advises. If you're outside, stay outside. If you're in a car, "stop as quickly and safely as possible," the CDC says.

"Remember to drop, cover, and hold on if you feel shaking," Jessica Jobe of the USGS said in the briefing. "No one can predict the exact time or place of any earthquake, including the aftershocks."

Read more about what to do in different situations, such as in a high-rise or stadium, on the CDC website.