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�.► Factors influencing vulnerability include , but are not necessarily limited to a community's location , type of construction , demographics , and cultural characteristics . Table 4 . 1 lists the general hazards to which Indian River County is vulnerable and indicates their projected impact potential across the entire spectrum of community exposure and services . The hazards identified in Table 4. 1 and discussed here are organized based on the maximum projected impact potential ( i . e . , hazards capable of producing the maximum community-wide impact , such as hurricanes and floods , are discussed first) . This does not mean other identified hazards are less important or less worthy of mitigation , only that their potential to affect the total community is lower. In order to effectively plan hazard mitigation projects and allocate s arce financial resources , a community' s vulnerability to a specific hazard must be coupled w th other critical factors to perform a risk assessment. Risk , or the probability of loss depends on three elements : 1 ) Frequency — How frequently does a known hazard produce an impact within the community? ; 2 ) Vulnerability — How vulnerable is a community to the impacts produced by a known hazard ? ; and 3 ) Exposure — What is the community' s exposure in terms of life and property to the impacts produced by a specific hazard ? Once these three factors are established , the risk level faced by a community W4 "' with regard to any specific hazard can be calculated using the " Risk Triangle" approach ( Crichton , 1999 ; see Figure 4 . 1 ) . In this approach , these three factors become the sides of a triangle and the risk or probability of loss is represented by the triangle ' s area ( Figure 4. 1 a ) . The larger the triangle , the higher the community' s risk with respect to a given hazard . If a community reduces any of these three factors , they reduce their risk of potential for loss . or example , if a community reduces its exposure to hurricanes , as has actually happened historically , by moving from a barrier island to the mainland , they will reduce their exposure and therefore their risk of loss ( Figure 4 . 1 b ) . Likewise , if a community reduces its vulnerability to hurricanes by strengthening its buildings , it also will reduce its risk of loss ( Figure 4 . 1c) . In terms of natural hazards , there is very little if anything that can be done to change the frequency with which they produce impacts in a community . Mitigation planning relative to those hazards must therefore focus on reducing the community' s vulnerability or exposure . In terms of technological and societal hazards , the most cost-effective type of mitigation is to limit or reduce the frequency with which such hazards actually ) ccur. At the time of publication , detailed risk assessments were only available for floods and hurricanes . Data sources used to prepare the hazard vulnerability and risk assessments are documented in Appendix D . 4-2