The minimum acceptable distance that must separate storage tanks from property lines, nearby buildings and other tanks. Fire codes require that both underground and aboveground tanks be positioned in accordance with minimum separation distances. 

In addition to public-safety considerations, the fire code requirements are intended to reduce the fire exposure of tanks and to ensure adequate space for fighting a fire, should one occur. 

Industry recommended practices, such as PEI/RP100, Recommended Practices for Installation of Underground Liquid Storage Systems, also stipulate minimum separation distances between tanks, and between tanks and nearby buildings.