The aim of this work was to investigate the influence of pH, recovery volume, type of saline solution plastic or glass container, used to prepare the technetium-99m-d,l-hexamethylpropyleneamineoxime ([99mTc]Tc-d,l-HMPAO] radiopharmaceutical starting from generator produced sodium pertechnetate in nuclear medicine routine preparations. We observed that, neither the container type, nor the pH of 0.9% NaCl, used for diluting the [99mTc]pertechnetate, influenced [99mTc]Tc-d,l-HMPAO radiochemical purity (RCP) and stability, that decreased proportionally with the final volume of the preparation. In particular, the RCP of 1 mL kits preparations, at 30 min was found to be less than 80%.