Should be considered as a guide on new tank installations and maintenance of existing tanks. It contains recommendations for good practices in a) the collection of well or lease production, b)gauging, c) delivery to pipeline carriers for transportation, and d)other production storage and treatment operations. This recommended practice is intended primarily for applications to tanks fabricated to API Specs 12F, 12D, 12F, and 12P when employed in on-land production service; but its basic principles are applicable to atmospheric tanks of other dimensions and specifications when they are employed in similar oil and gas production, treating, and processing services. It is not applicable to refineries, petrochemical plants, marketing bulk stations, or pipeline storage facilities operated by carriers.