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82	HAZARDS CONCLUSIONS Of the more than 20 large-volume edifice collapse events during the past 500 years, the majority were associated with magmatic eruptions. However, MSH-style lateral blasts occurred at only a few eruptions, and a significant percentage of slope failures involved either phreatic eruptions or no eruptive activity. Both magmatic and non-magmatic failures can occur at the same volcano, as at Bandai-san in Japan. Failure volume and potential hazard appear to be independent of the type of associated eruptive activity. Major hazards can result from phreatic and non-eruptive events as well. In fact, during historical time, these events produced the greatest number of fatalities. Smaller-volume failures occur much more frequently than larger ones. They typically occur without associated eruptions, but as we’ve seen recently at Casita volcano in Nicaragua, they also have major hazard implications. Precursors remain poorly understood, however, non-magmatic failures are more likely to occur suddenly, at the onset of eruptions, and with shorter seismic warning.