[en] Studied are angular distributions of integral characteristics of secondary hadrons generated by 69 GeV protons on aluminium, copper and tungsten targets of different sizes. Measurements were made on an extracted proton beam. The comparison of results for thin and thick targets indicates that the secondary radiation outputs increase with the target thickness along the beam especially at large angles. The outputs also increase as the target atomic number increases. The output of hadrons with E > 2 GeV from the thin target for one interacting proton is higher than that from the thick target; and at the same time the output of hadrons with lower energy thresholds is in average two times higher for thick targets, which is due to the influence of secondary interactions in the target material