Protection of oil storage tanks against direct lightning strikes: Self protection scheme or standalone LPS?

Lightning protection of oil storage tanks has becomes a controversial subject, due to conflicting protection criteria. One such is the sense of using self-protection criteria, relying on the strict fulfillment of the operational conditions, material thickness and reliable bonding; the other refers to the necessity of standalone lightning protection system (LPS) where air terminals are installed in order to avoid any interception between the lightning stepped leader and the tank body that could cause hot spots and excessive temperature rise. Each method has its own advantages and drawbacks. In this paper these criteria are analyzed with critical view in order to make appropriate decisions in selecting the most suitable method of protection for a given situation.