A relevant part of deadly work accidents and of severe work accidents reported in national specific statistics coming from INAIL is until today caused by workers' falls during their at height work activities. Medical evaluation of eventual workers' hyper susceptibility to fall caused by balance alterations, if included in medical surveillance, is frequently carried out by medical doctors using different subjective tests included in different clinical protocols. Use of a computerized stabylometric footboard on the contrary allows to obtain objective and reproducible data concerning vestibular function which, associated with traditional clinical medical evaluation, seem to better detect eventual presence of balance disturbances, especially those non clinically perceivable by workers and therefore more dangerous. We report results evidenced in a research carried out in a group of 185 workers engaged in building firms and having work tasks including phases of at height work.