In reality few hazards have identical causes, identical magnitudes and intensities, and identical patterns of development.   Classes of hazards are not uniform in their range of occurrence, impacts, or timelines.  And in most cases they are neither exclusive nor transposable.  The occurrence of a tropical cyclone does not preclude the occurrence of an earthquake (the idea that changes in atmospheric pressure associated with a hurricane may trigger seismic events has been proposed).   One hazard generally will not substitute for another, at least at the higher level of classification.  For example, in your hazard analysis an earthquake will not have the same characteristics as a railway accident.  It should be noted that a lower level, a railway passenger train accident involving mass casualties can occur in the same fundamental way that a freight (or goods) train accident involving hazardous materials.

Because hazards are not the same, we must examine each hazard that we identify to determine its characteristics in the context of the time and place in which it is likely to impact our locality or our organization.