Problems with the floating disk seal in storage tanks

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\"Emission Standards for Pollutants in the Petroleum Refining Industry GB 31570-2015\" 5.2 Requirements for Pollution Control of Volatile Organic Liquid Storage Tanks 5.2.1 New enterprises shall comply with the following requirements for pollution control of volatile organic liquid storage tanks as of July 1, 2015, while existing enterprises shall do so as of July 1, 2017. 5.2.2 Pressure storage tanks shall be used for storing volatile organic liquids with a true vapor pressure of ≥76.6 kPa. 5.2.3 Volatile organic liquid storage tanks with a design volume of ≥150 m³ that store liquids with a true vapor pressure of ≥5.2 kPa but <27.6 kPa, as well as storage tanks with a design volume of ≥75 m³ that store liquids with a true vapor pressure of ≥27.6 kPa but <76.6 kPa, shall comply with one of the following requirements: a) Use internal floating roof tanks ； High-efficiency sealing methods such as liquid interlocking, mechanical shoe type, and double-seal type should be used between the floating disk of an internal floating roof tank and its tank wall. b) Use external floating roof tanks ； A double-seal design should be employed between the floating disk and the tank wall of external floating roof tanks, with the primary seal using efficient sealing methods such as liquid-filled or mechanical shoe-type seals. c) When a fixed-roof tank is used, a sealed exhaust system shall be installed to lead the organic waste gas to a recovery or treatment unit. Do nitrile-sealed naphtha storage tanks also require efficient sealing methods such as liquid-set, mechanical shoe-type, or dual-seal types?