how does queequeg's position endanger ishmael

Basically they use a "monkey rope" to butcher the whale. This process involves Ishmael, (Queequeg’s bowsman) who holds Queequeg’s harness. A rope is tied to both their belts so Queequeg falls into the sea and drowns, Ishmael will be pulled in after him. They are "wedded" together so to speak.