Solvent vessels must be purged before maintenance personnel enter in order to ensure that: (1) sufficient oxygen is available for breathing; (2) vapor concentrations are below the flash point; (3) vapor concentrations are below the occupational safety and health admin- istration (osha) limits if breathing apparatus is not to be used. assuming that a 8 m3 fixed-roof solvent tank has just been drained of all liquid and that the vapor phase is ini- tially saturated at 22c, estimate the length of purge necessary with 2 m3/min of gas at 0.1 mpa and 22c to reach the osha 8-hr exposure limit.1