Explain how earthquake-hazard level is determined. Compare methods of earthquake forecasting. Describe five ways to safeguard buildings against earthquakes. Outline earthquake safety procedures. Seismologists are not able to predict the exact time when and place where an earthquake will occur. They can, at best, make forecasts based on the frequency with which earthquakes take place. Earthquake hazard is a measurement of how likely an area is to have damaging earthquakes in the future. An areas earthquake-hazard level is determined by past and present seismic activity. The greater the seismic activity, the higher the earthquake-hazard level. Forecasting when and where earthquakes will occur and their strength is difficult. By looking carefully at areas of seismic activity, seismologists have discovered some patterns in earthquakes that allow them to make some general predictions. Earthquakes vary in strength. And you can probably guess that earthquakes dont occur on a set schedule. But what you may not know is that the strength of earthquakes is related to how often they occur. Table 1 provides more detail about this relationship worldwide. Great 8.0 and higher 1 Major 7.0 Strong 6.0 Moderate 5.0 Light 4.04.9 about 6,200 Minor 3.03.9 about 49,000 Very minor 2.02.9 about 365,000 Another method of forecasting an earthquakes strength, location, and frequency is based on the gap hypothesis. The gap hypothesis is a hypothesis that states that sections of active faults that have had relatively few earthquakes are likely to be the sites of strong earthquakes in the future. The areas along a fault where relatively few earthquakes have occurred are called seismic gaps. Today, older structures in seismically active places, such as California, are being made more earthquake resistant. The process of making older structures more earthquake resistant is called retrofitting. A common way to retrofit an older home is to securely fasten it to its foundation. A lot has been learned from building failure during earthquakes. Armed with this knowledge, architects and engineers use the newest technology to design and construct buildings and bridges to better withstand earthquakes. The first thing you should do is safeguard your home against earthquakes. You can do so by putting heavier objects on lower shelves so that they do not fall during the earthquake. You can also talk to a parent about having your home strengthened. Next, you should find safe places within each room of your home and outside of your home. Then, make a plan with others (your family, neighbors, or friends) to meet in a safe place after the earthquake is over. This plan ensures that you will all know who is safe. During the earthquake, waterlines, power lines, and roadways may be damaged. So, you should store water, nonperishable food, a fire extinguisher, a flashlight with batteries, a portable radio, medicines, and a first-aid kit in a place you can access after the earthquake.