Oldfieldguy
Bronze Member
I found this to be very interesting since I've always wondered the anwer to the question of emergency vents on aboveground storage tanks.
http://library.constantcontact.com/download/get/file/1102248019668-297/Emergency+Venting+and+Class+IIIB+Liquids.pdf
http://library.constantcontact.com/download/get/file/1102248019668-297/Emergency+Venting+and+Class+IIIB+Liquids.pdf