scope:

The procedures presented herein utilize the results of a comprehensive study of the available evaporation loss test data from fixed-roof tanks. The test data, and hence the results, are limited to liquid- and vapor-tight tanks with vertical, cylindrical shells and fixed roofs. The tanks are also assumed to be equipped with tight fittings and to operate approximately at atmospheric pressure. As stated previously, this pressure is usually. ³/₄ in. of water or ¹/₂ oz per sq in.

The major portion of this bulletin is directed toward calculations of losses of petrochemicals from fixed-roof tanks. However, Section 4 suggests how the described principles and method can be applied to conservation tanks.

Appendix I lists the physical properties of common organic compounds. These compounds were selected on an arbitrary basis of having at least a 1 psia vapor pressure at 100 F. The constants listed are suitable for use in calculation methods of losses described in this bulletin.