Gases and vapors are no longer ignitable at room temperature and atmospheric pressure when the oxygen content in the inerted mixture is less than 10% vol. Instead of inertization the term inert gas blanketing is usually used for tanks. A pillow of inert gas or atmosphere is lying above the liquid phase. The tank gas phase being inerted is connected to an inert gas supply net. Which of these systems the most favorable is depending on the amount of N2 required. This is depending on liquid AFR consumption, tank sizes/pressure design and climate. For continuous and stable N2 consumption, on-site inert gas generation becomes quickly economic.