Is the crude oil pipeline a pressure pipeline?

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Question: For a atmospheric pressure external floating roof crude oil storage tank with a capacity of 40,000 m³, a diameter of 52 m, and a height of 18.85 m, does the crude oil outlet pipe at the bottom of the tank qualify as a pressure pipeline? According to the definition of pressure pipelines in the catalog of special equipment: “A pressure pipeline is a tubular device that uses a certain pressure to transport gases or liquids. It refers to pipelines with a maximum operating pressure of 0.1 MPa (gauge pressure) or more, whose medium is gas, liquefied gas, steam, or a liquid that is flammable, explosive, toxic, corrosive, and has a maximum operating temperature equal to or higher than its standard boiling point, and whose nominal diameter is 50 mm or more.” Except for pipes with a nominal diameter of less than 150 mm and a maximum operating pressure of less than 1.6 MPa (gauge pressure), as well as the pipes that form part of the equipment used for transporting non-toxic, non-flammable, and non-corrosive gases. ”In other words, if the pipeline contains crude oil, has a diameter of ≥DN50, and an operating pressure of ≥0.1 Mpa (G), it should be classified as a pressure pipeline, regardless of the source of this operating pressure – whether it is generated by a pump or by the hydrostatic pressure of the liquid. Is that correct? Or does the operating pressure of pipelines connected to equipment at atmospheric pressure (without any other equipment used to apply pressure) remain the same as that of the atmospheric-pressure equipment, with no need to take the hydrostatic pressure into account? Now, the client has proposed that the original crude oil outlet pipes at the bottom of its atmospheric pressure external floating roof crude oil storage tanks were all designed, constructed, and managed as non-pressure pipelines; and they would like the newly added pipes of the same type to be designed as non-pressure pipelines as well. Is this feasible? Are there any other standard specifications or regulations that I haven’t seen or understood yet? Please discuss more.