Why are eruptions on Hawaii less dangerous than those of the Cascades?

It is because the Hawaiian Volcanoes are Shield Volcanoes. They are the largest type of volcano. They tend to not have violent eruptions but have been know in the past to have some what violent explosions involved with them. The Cascades Range is made up of Composite volcanoes. These volcanoes tend to always have violent eruptions. Shield volcanoes are very wide and the change in elevation as you go up is not very high. Composite Volcanoes Are very steep.