Whether it is natural or man-made, you have to survive the initial event or it is game over. In many cases, however, survival comes down to sheer luck or God’s grace, whichever you believe in. A tornado may make a direct hit on you, an earthquake could drop the building on you, or an airliner could come down on you. In short, you might just be in the wrong place at the wrong time.
There are ways to put the odds in your favor. An easy way is to know where to run to in the building you work in where it would be safer in during an earthquake or tornado, or at the least the closest thing to duck under (desk, etc.). Standing by a large window won’t cut it, but may cut you. Knowing escape routes in case of fire, or other emergencies will also help.
On the harder side is moving to safer areas of the country. With jobs and the economy, this is a luxury few can afford, but it should be considered if possible. No area is immune, but some areas, such as the one I live in, have a less than 10% chance of tornado and earthquake, and zero chance of flooding. There are still other risks, but they are generally less than most areas. Unfortunately, this area has a very bad economy.
While living and working in a major city area can offer more and better paying jobs, the costs are usually more, and they stand higher risks of being targets for terrorists, and for urban unrest, riot, looting and disruption, especially if anything disrupts the normal grid for any period of time.
The choice is yours.