Any industrial plant requires the storage of large quantities of raw materials, for processing, and final products, for shipping. Furthermore, it is also necessary to store intermediate products from front-end process units, to be utilized as feed for the next units. Quantities are always significant, especially in the case of oil refineries, where the storage of strategic stocks should be taken into account according to local regulations.

Therefore, storage tanks are not stand-alone equipment: each of them plays a role in the industrial complex, requires an appropriate location and a link with process units, consisting in extensive piping, pumping facilities and associated electrical and instrumentation systems.

The presence of large quantities of flammable and, sometimes, toxic fluids also involves an accurate fire-fighting system, along with alarm and emergency shut-down systems.