
Quantitative Risk Estimation Model ◾ 191
e vulnerability of an infrastructure or its system component is estimated
using the probability scale in decimal description provided in Table 5.3. is esti-
mates the potential terrorism or disaster occurrence of the given events from the
event tree analysis. Categories 3 and 4 are further subdivided to provide more
renement as the likelihood of success approaches to 1.0. is allows the owner,
decision-maker, or analyst to intuitively measure changes in security and defense
level. Infrastructure evaluations will depend upon the judgment of an expert based
on experience and knowledge.
5.4.1 Calculatio ...