Electropolished (EP) Nb samples were investigated by a dc field emission scanning microscope, which has recently been modernized for the fast scans on large samples. Measurements on EP samples before and after high pressure rinsing (HPR) are compared. Repro-ducible voltage scans at various surface fields have been obtained partially down to lm resolution. The statistical overview of the density of emitting sites at 120 MV/m shows a reduction from about 30 before to 14 emitters/cm 2 after HPR. Local measurements of selected emitters prove increased onset fields E on at 1 nA and decreased values after HPR. High resolution SEM images and EDX measurements of the identified emitters will also be presented.