ISO 20257-1的目标是为浮动液化天然气（LNG）设施的设计提供功能准则和建议做法，以便有安全和环保的设计和运行浮式LNG装置。 ISO 20257为所有浮式液化天然气装置的设计和运行提供了功能准则，包括液化，储存，蒸发，转移和处理液化天然气

This document provides requirements and guidance for the design and operation of floating liquefied natural gas (LNG) installations, including installations for the liquefaction, storage, vaporisation, transfer and handling of LNG, in order to have a safe and environmentally acceptable design and operation of floating LNG installations. This document is applicable to: — floating LNG liquefaction installations (plant) — FLNG; — floating LNG regasification installations (plant) — FSRU; — floating storage units — FSU. This document is applicable to offshore, near-shore or docked floating LNG installations. This document includes any jetty in the scope in case of docked floating LNG installations with regards to the mooring. This document briefly describes floating LNG mooring concepts. This document is applicable to both newbuilt and converted floating LNG installations, and addresses specific requirements. This document is not applicable to: — onshore LNG storage, liquefaction and/or regasification installations/plants, except for docked FSRU and/or FLNG installations; — offshore LNG plants based on non-floating structure (such as gravity based structure [GBS] principle); and — support onshore based facilities (such as support vessels, tugs, etc.). This document is not intended for design floating power generation facilities though relevant parts of this document can be used. This document is not intended to cover LNG as fuel bunkering applications.