Scenarios are chosen based upon the flammable or toxic components in the process as well as parameters such as pressure, temperature and phase of the material. Once a release is chosen, detailed equipment counts are performed in order to define the probability of the accident occurring.
Quest uses the equipment counts, as well as the probability of failure of the individual types of equipment, to determine the probability of occurrence of a single accident. The timing and probability of ignition is used to determine the outcomes of a release. Following the mapping of the hazard maps and the associated probability of occurrence yields us risk contours.
The last step in the analysis is to determine the probability that some portion of the population (or worker population)is exposed at any given time. This additional step yields societal risk measures (e.g. f/N curves).
