Section 1 General

101. Application

1. The requirements in the Guidance are to be applied to the surveys, hull construction, equipment and machinery of Floating liquefied gas units. Floating liquefied gas units(hereinafter referred to as "units" in the Guidance) as used herein mean units or ships, which are positioned at a specific site of the installation permanently or for long periods for storage and loading or offloading of liquefied gas and units are classified into floating liquefied gas production units(FLNG) and floating liquefied gas storage and regasification units(FSRU).

2. Attention is to be paid to plied to the International Conventions and National Regulations of the coastal state in which the unit is located during operation, and statutory requirements of the International Conventions and the National Authority may be stricter than requirements of this Guidance.

102. Types of units

1. Ship Type Units

Ship type unit is a seagoing ship-shaped unit having a displacement type hull or hulls, of the sin- gle, catamaran or trimaran type, which have been designed or converted for operations in the float- ing condition. The unit of this type has propelling machinery.

2. Barge Type Units

Barge type unit is a seagoing unit having a displacement type hull or hulls, which have been de- signed or converted for operations in the floating condition. The unit of this type has no propelling machinery.

3. Units other than those specified in Par 1 to Par 2 are to be in accordance with the relevant re- quirements in this guidance and are to be at the discretion of the Society.

103. Equivalence and novel features

1. The construction and equipment, etc. which are not in compliance with the requirements of the Guidance but are considered to be equivalent to those required in the Guidance will be accepted by the Society.

2. The Society may consider the classification of the construction and equipment based on or applying novel design principles or features, to which the Rules are not directly applicable, on the basis of experiments, calculations or other supporting information provided to the Society.

3. The risk evaluation of 104. may be applicable for justification of equivalence or novel features.

104. Risk evaluation

1. A risk evaluation is be carried out to identify significant hazards and accident scenarios that may affect the installation or any part thereof, and consider the benefit of existing or potential risk con- trol options.

2. The objective of the risk evaluation is to identify areas of the design that may require the im- plementation of risk control measures to reduce identified risks to an acceptable level. For this pur- pose, a systematic process is to be applied to identify situations where a combination or sequence of events could lead to undesirable consequences such as property damage, personnel safety and en- vironmental damage at an acceptable frequency.

3. The risk assessment is to consider the following events as a minimum.

(1) Damage to the primary structure due to extreme weather, impact and collision, dropped objects,

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helicopter collision, exposure to unsuitably cold temperature, exposure to high radiant heat

(2) Fire and explosion

(3) Loss of primary liquid containment(for a duration to be determined based on an approved con- tingency plan)

(4) Leakage of liquefied gas

(5) Release of flammable or toxic gas

(6) Roll-over

(7) Loss of stability

(8) Loss of any single component in the station keeping and mooring system

(9) Loss of ability to offload liquefied gas or discharge gas ashore

(10) Loss of any one critical component in the process system

(11) Loss of electrical power

4. The identified risk control options(prevention and mitigation measures) deemed necessary to be im- plemented should be considered part of the design basis of the unit.

5. Approval process of Risk-based design is to comply with Guidance for Approval of Risk-based Ship Design.

105. Conversion of LNG carriers to units

LNG carriers may be converted and registered to units. The ship's existing systems and structures unaffected by the new application would be acceptable as is, however it should be assessed wheth-

er such are affected by

issues such as different operational modes, modified maintenance schedules

and differing accidental loads compared to the initial design. If the existing structure and systems

onboard continuously, it

should be assessed for the planned service life of the units.