Section 3 Risk based analysis

3.1.1 The purpose of the risk based analysis is to:

1. evaluate safety considerations that are specific to the regasification and send-out equipment, see Ch 1, 3.2 System safety risk assessment;

2. evaluate dependability of the regasification plant, see Ch 1, 3.3 System dependability;

3. specially consider arrangements which deviate from the requirements of these Rules, see Ch 1, 3.2 System safety risk assessment.

3.2.1 The objectives of the assessment are to:

1. evaluate safety risks associated with the use of the regasification system where the requirements within these Rules are not satisfied;

2. evaluate safety risks associated with the use of the regasification system where specifically required by these Rules;

3. for Ch 1, 3.2 System safety risk assessment 3.2.1 and Ch 1, 3.2 System safety risk assessment 3.2.1.(b), demonstrate that an appropriate level of safety is achieved, which is commensurate with that generally accepted for the transportation of LNG cargoes through compliance with LR’s Rules for Ships for Liquefied Gases.

3.2.2 Where the risks cannot be eliminated, an inherently safer design shall be sought in preference to operational/ procedural controls. This shall focus on engineered prevention of failure (e.g. a minimised number of connections, increased reliability, and redundancy).

3.2.3 The risk assessment may identify the requirement for safety measures in addition to those specifically stated in these Rules.

3.2.4 The scope of the risk assessment may include but not be limited to:

1. normal operation, start-up, normal shutdown, non-use, and emergency shutdown of the system, including:

   • pressurised gas discharge to shore;
   • high pressure gas venting;
   • storage and handling of flammable refrigerants (as applicable);
   • continuous presence of liquid and vapour cargo outside the cargo containment system;
   • ship-to-ship transfer of liquid cargo.

2. physical equipment layout, machinery and equipment layout, arrangements and location, including extension of hazardous areas and evacuation arrangements;

3. fire and explosion, process upset conditions, over-pressure and under-pressure, mechanical and electrical failures and human error.

3.2.5 The risk assessment shall be undertaken by suitably qualified and experienced individuals to a recognised Standard (e.g. as outlined in ISO/IEC 31010-2009: Risk management – Risk assessment techniques) in accordance with LR’s ShipRight Procedure Risk Based Certification (RBC) and the associated Annex on LNG.

3.2.6 The risk assessment shall specifically address the following aspects:

1. fire and explosions in areas or spaces containing piping, machinery, equipment and components;

2. fire and explosions adjacent to areas or spaces containing piping, machinery, equipment and components;

3. cryogenic leakage from piping, equipment and components associated with the regasification system;

4. corrosion/erosion in gas high pressure piping, components and tanks associated with the regasification system;

5. mechanical failure in regasification machinery, equipment or components;

6. control/electrical failure in regasification machinery, equipment or components;

7. manufacturing defects in equipment and machinery;

8. human error in operation, maintenance, inspection and testing of regasification machinery, equipment and components;

9. location of piping, machinery, equipment and components;

10. cargo tanks over-pressure and under-pressure situations associated with the regasification and ship-to-ship transfer operations;

11. analysis of risk associated with the ship-to-ship LNG transfer in accordance with ISO 28460:2010 Petroleum and natural gas industries – Installation and equipment for liquefied natural gas – Ship-to-shore interface and port operations and the relevant parts of EN 1474 as applicable, and SIGTTO LNG Ship-to-Ship Transfer Guidelines;

12. process upsets associated with the land-based receiving systems;

13. jet fires and blast.

3.2.7 Where a risk assessment or study of similar intent is utilised within these Rules, the results shall also include, but not be limited to, the following as evidence of effectiveness:

1. description of methodology and standards applied;

2. potential variation in scenario interpretation or sources of error in the study;

3. validation of the risk assessment process by an independent and suitable third party;

4. quality system under which the risk assessment was developed;

5. the source, suitability and validity of data used within the assessment;

6. the knowledge base of persons involved within the assessment;

7. system of distribution of results to relevant parties; and

8. validation of results by an independent and suitable third party.

3.3.1 Where Class Notation Lloyd’s RGP+ is to be applied, an assessment shall be carried out to demonstrate that a fault in any active component or system will not result in reduced availability of the plant to regasify the LNG cargo and send-out gas.

3.3.2 The level of availability of the regasification system shall be specified by the Owner, see Ch 1, 2.2 Systems and arrangements 2.2.2.

3.3.3 The assessment shall be undertaken by suitably qualified and experienced individuals using approaches acceptable to LR.