Most sources seem to recommend having enough to survive for three days without help. I recommend at least two weeks, if not a month without assistance. Water is the most important item. My family carries a case of water bottles in our cars. You never know where you may get stuck. My plan is to be able to survive for at least three days if I am out in the car and for at least a month if I am home. Having an extra pair of sturdy shoes in the car is helpful too, especial for women who tend to wear flimsy shoes much of the time.
Extra clothing and a blanket are important items as well. When we buy a new blanket, I save the plastic bag it comes in and put the old blanket in the new plastic bag. I then have an instant and free emergency blanket. It goes into a closet or into a car or storage shed that does not have a blanket. If it starts to rain after the earthquake knocks your house down, an extra dry blanket from the car trunk will come in handy; that’s what the SGT Says.