In this video, we'll take a closer look at the SAFE-Surge manway cover, designed specifically for pneumatic-filled polyethylene chemical storage tanks. The SAFE-Surge manway cover releases at a 6-inch water column to prevent over-pressurization, ensuring that the tank maintains proper ACFM at all times -- even in the event of air surges that cannot be handled by primary venting. Available in 19 and 24 inches.