Force field (terran)

Force fields are energy-based shields (not to be confused with Protoss shields which are powered by psionic powers) which can be issued to protect buildings, personnel the Wraith and even people (such as Wrangler Malcolm Kelerchian).

Of buildings and personnel, it could apparently "stop anything short of a nuke." Almost certainly an exaggeration but force fields issued to personnel can at least grant complete immunity to small arms fire and at full power, can protect the wearer from debris, although injuries may still result.