Justrite drums of flammable liquids require venting to relieve pressure build-up due to heat and also to prevent creation of a vacuum when liquid is being drained off or the drum is subjected to sudden cooling. Either pressure or vacuum can cause failure of the container. In event of fire, the hazards of drum leakage or explosion due to excessive pressure build-up can be catastrophic. Justrite drum vents provide automatic pressure relief. Operating valve opens at five psig internal pressure in normal service. Vacuum relief is manual or automatic depending on the model and permits four or more gpm flow through a standard 3/4-inches faucet. All vents include a flame arrester for added safety. Justrite Aerovent; safely vents drums at 5 psig and controls fugitive emissions. Brass body with an activated process carbon filter effectively adsorbs vapors preventing escape to the atmosphere during the exhale cycle to capture VOCS. Pressure and vacuum relief are automatic. Built in flame arrester prevents flashback from external ignition sources. The filter may be easily replaced when odors in the area indicate the filter has been utilized to capacity.