Tanks designed to have a pressure above 10 pounds per square inch are?

Pressure tanks are specifically designed to operate with internal pressures above atmospheric levels, typically exceeding 10 pounds per square inch gauge (psig). This design is essential for safely containing and transporting liquids and gases that require being maintained at pressures greater than the surrounding atmosphere.

These tanks employ robust construction and materials to withstand the increased stress and pressure, which can result from the stored material's characteristics or the environmental conditions during transportation. Common applications for pressure tanks include the storage of liquefied gases, chemicals, and other volatile substances where containment under pressure is necessary to maintain their state and prevent evaporation or leakage.

In contrast, atmospheric tanks operate under normal atmospheric pressure without the need for additional pressurization, vacuum tanks are built to handle substances at pressures below atmospheric levels, and refrigerated tanks are used specifically for substances that need to be kept at low temperatures, which may or may not involve pressure considerations.