Twenty years after a strong earthquake struck Los Angeles and surrounding communities, engineers say buildings around the region remain vulnerable.
There has been an effort to strengthen freeways and hospitals, but there has been less attention paid to concrete buildings and housing with ground-floor parking.
The Northridge quake hit before dawn on January 17, 1994. Within seconds, freeway overpasses collapsed, buildings were ruined and fires ignited. Several dozens were killed and more than 9,000 were injured.
City building inspectors recently proposed to survey 30,000 apartments built before 1978 to determine which might be compromised during violent shaking.
Earlier this week, the city announced a partnership with government scientists to develop a plan to address seismic safety including ways to get privately-owned buildings to be more quake-proof.
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