MICHEL MARTIN, HOST:
Thirty years ago today, a powerful earthquake struck Northridge. That's a neighborhood in Los Angeles.
(SOUNDBITE OF ARCHIVED RECORDING)
UNIDENTIFIED PERSON: I have never, ever seen anything like this, obviously, in Los Angeles. The Santa Monica Freeway at La Cienega...
STEVE INSKEEP, HOST:
The earthquake killed 72 people and injured thousands.
MARTIN: At the time, Mark Benthien was a student studying geophysics.
MARK BENTHIEN: The earthquake was at 4:31 in the morning. Of course, everything fell onto the floor, and I had to kind of climb through that.
INSKEEP: The costliest earthquake in American history, causing billions of dollars in damages.
MARTIN: Benthien is now director for outreach for the Earthquake Center at the University of Southern California. He says the quake exposed structural vulnerabilities in California.
BENTHIEN: We learn what type of damage they can cause. Then, we try to prevent that damage in the future by updating the building code for new construction as well as requiring some older, most vulnerable buildings to be retrofitted.
INSKEEP: Janiele Maffei is chief mitigation officer with the California Earthquake Authority...
JANIELE MAFFEI: What a retrofit does is it goes back into an older structure and introduces new structural elements. And in the case of houses - they're predominantly wood-frame in California - it puts in new bolts and plywood and framing clips - the kinds of things that you see at your local hardware store.
INSKEEP: ...And she says retrofitting buildings can save lives.
MARTIN: The U.S. Geological Survey released a study finding most of the U.S. could experience damaging earthquake shaking.
MARK PETERSEN: For many parts of the country, the hazard has increased. We've found that some of these places are more susceptible to earthquakes than we had previously thought.
MARTIN: That's Mark Petersen, the lead author of the National Seismic Hazard Model Report. He helped create a map to plot out where earthquakes are more likely to occur in the U.S.
INSKEEP: And while California has updated some safety standards since that earthquake 30 years ago, there are still many vulnerable places in the United States that require retrofitting.
(SOUNDBITE OF MUSIC) Transcript provided by NPR, Copyright NPR.
NPR transcripts are created on a rush deadline by an NPR contractor. This text may not be in its final form and may be updated or revised in the future. Accuracy and availability may vary. The authoritative record of NPR’s programming is the audio record.