LPG storage vessels are designed according to which code?

• A. NFPA 58
• B. ASME Section VIII
• C. API 650
• D. ASTM E18

Answer: (B)

LPG storage vessels that hold LPG under pressure are treated as pressure vessels and must be designed to the ASME Boiler and Pressure Vessel Code, Section VIII. This code provides the rules for the entire design process—allowable stresses, minimum wall thickness, reinforcement around openings, corrosion allowances, weld quality, fabrication, inspection, testing, and certification—so the vessel can safely withstand internal pressure during operation. NFPA 58 deals with the safety and handling of LPG installations and provides guidance for siting, venting, piping, and overall system safety, but it does not dictate the primary design rules for the pressure-containing vessel itself. API 650 covers large atmospheric storage tanks for liquids with little to no internal pressure, which isn’t the typical scenario for LPG storage vessels. ASTM E18 is a hardness testing standard and not related to vessel design. Hence, ASME Section VIII is the best fit for designing LPG storage vessels.