scope:

This bulletin is the result of a study of the available test data on evaporation loss from cone-roof tanks. Inasmuch as the test data did not include crude oil containing significant amounts of ethane and methane, the equations in this bulletin may or may not apply to production lease tanks. The test data, and hence the results, are limited to tanks with vertical cylindrical shells and fixed roofs. The tanks are substantially liquid and vapor tight. They are equipped with tight fittings and operate at approximately atmosphere pressure.