An EV team was a group of officers who carried out expeditions to the outside of a starship's hull.
While Enterprise NX-01 was in a polaric field in 2153, an EV team was deployed from the vessel in order to obtain a sample of nucleonic particles. The team eventually acquired such a sample from the ship's hull but had to fire multiple hits from a plasma rifle at the particles before they would dislodge from the hull. (ENT: "Similitude")