SAN FRANCISCO — As residents on both sides of the Mexican border cleaned up after Sunday’s earthquake, the authorities warned that many Californians remained unprepared for a serious quake, and emergency officials said that budget cuts have strained their ability to handle a disaster.
This earthquake was strongly felt over a long distance, which I find is unusual for California. Large numbers of elevators were powered off because of overly sensitive sensors. The design of the sensor makes it very sensitive to low frequency ground motions, with a PGV of perhaps a few millimetres/sec. They should only cut off at something like 5-10 cm/sec, since having large numbers of people stuck is a hazard in itself.