How is the capacity of ASME containers expressed?

The capacity of ASME (American Society of Mechanical Engineers) containers is expressed in terms of the maximum amount of water gallons that the container can hold. This measurement is significant because it relates to the volume the container can safely contain and allows for proper calculations regarding the amount of liquefied petroleum gas (LPG) that can be stored without exceeding safety limits. The water capacity of a container is a standardized measure that helps ensure uniformity and safety in the handling and storage of propane and other LP gases.

While other measures such as liters or cubic meters could theoretically express volume, they are not the standard used in the context of ASME containers. Additionally, expressing capacity in pounds of propane could create confusion since it would depend on the density of the propane at a given temperature and pressure, which can vary. Therefore, the use of maximum water gallons provides a clear, consistent, and safe reference for the capacity of these containers.