To reduce risk of the bends, a mixture of helium and oxygen is used as a breathing gas for deep-sea diving, since helium is less soluble in human blood than nitrogen.
(a mixture of helium and oxygen; is used; as a breathing gas for deep-sea diving) (helium; is; less soluble in human blood than nitrogen)
a mixture of helium and oxygen helium
is used is
as a breathing gas for deep-sea diving
less soluble in human blood than nitrogen