Q. Safety considerations for storage tanks?

Large storage tanks are potential fire hazards and should be located at a lower elevation than other occupancies to prevent liquids or gases from flowing toward equipment or buildings; locate tanks downwind of other areas. Access roads for fire-fighting vehicles usually surround the bermed areas so fire-fighting can be administered from at least 2 sides of any tank. Where fire fighting foam is used from dry risers and a fire tender, the dry riser couplings shall be located behind a shield wall. The shield wall shall be upstream of the prevailing wind direction.

Proper spacing will greatly increase the safety of a tank farm. Space tanks so the thermal radiation intensity from an exposing fire is too low to ignite the contents of the adjacent tanks. Arrange atmospheric storage tanks and pressure vessels in rows not more than two deep and adjacent to a road or access way for adequate firefighting accessibility. Do not group or dike tanks storing incompatible product types together.

LPG and LNG storage spheres or bullets should be located in a safe area away from, downwind and downgrade, other process plant and hydrocarbon storage facilities. These tanks are located in a walled paved area, sloped towards an evaporation dike, so any leakage of heavier than air gases can be safety contained.