Section 1 Introduction
Clasification Society 2024 - Version 9.40
Clasifications Register Guidance Information - Guidance Notes for Nearshore Hull Structures, April 2021 - Chapter 1 General - Section 1 Introduction

Section 1 Introduction

Parent topic: Chapter 1 General

1.1 General

1.1.1 These guidance notes aim to provide guidance regarding classification and certification of the units that will operate nearshore, at-shore or inshore (hereafter referred to as nearshore units). Nearshore units are defined in Ch 1, 1.3 Definitions. A nearshore unit may be a permanent installation or a disconnectable unit.

1.1.2 This document does not intend to replace requirements given in the Lloyd’s Register (LR) Rules and Regulations but to clarify and complement them for hull structural aspects. The nearshore units are still required to comply with relevant Rules and Regulations.

1.1.3 The following are examples of the nearshore units that can be considered in these notes:
  • Floating Storage Regasification Units (FSRU);
  • LNG Floating Production, Storage Offloading (LNG FPSO) units;
  • Floating Storage Units (FSU);
  • Floating Terminals (of various purposes);
  • Floating Power Plants.

1.2 Application

1.2.1 The following is offered to assist those concerned in the application of these guidance notes.

1.2.2 The guidance notes are applicable to ships or ship units which are intended to operate with applicable service restriction notations such as Protected waters service, Extended protected waters service, Specified coastal service and Specified operating area service.

1.2.3 The contents of this guidance may cover general design scenarios of nearshore units. Special consideration should be given on a case by case basis to the scenarios and load cases that are not covered in the guidance notes.

1.2.4 The content of this guidance relating to the design loads is specific to nearshore units. Specific service factors for the hull girder longitudinal strength assessment of ships or ship units are given in the guidance notes.

1.2.5 Application of class notation in the guidance notes is for example purposes only. It is recommended that the classification notations are agreed with LR prior to the contract stage.

1.3 Definitions

1.3.1 Definitions
  • Disconnectable units are self-propelled floating units which normally operate at a fixed location but are designed to disconnect from their moorings in order to avoid hazards or extreme storm conditions.
  • Extended protected waters service. Service in protected waters and also for short distances (generally less than 15 nautical miles) beyond protected waters in ‘reasonable weather’, e.g. ‘Extended Protected Waters Service from the Port of Lagos’.
  • Nearshore units are floating structures that will perform their primary service functions only while they are moored or anchored in shallow waters. These units are positioned nearshore, at-shore or inshore, operating alongside a jetty, dolphins, a sea island or similar. Thus, only a delivery transit(s) from the construction site to the installation site by the units’ own propulsion systems or by means of towing will be undertaken. A nearshore unit may be a permanent installation or a disconnectable unit.
  • Permanent installations are floating structures that are not designed to disconnect from the mooring system.
  • Protected waters service. Service in sheltered water adjacent to sand banks, reefs, breakwaters or other coastal features, and in sheltered water between islands, e.g. ‘Protected Waters Service at Storebaelt Bridge’.
  • Ship units are mono-hull surface type units engaged in production and/or oil/gas storage/offloading while permanently moored at offshore locations with a ship or barge hull form. Such units may be self-propelled or be built without primary propelling machinery.
  • Reasonable weather. Wind strengths of force six or less in the Beaufort scale, associated with sea states sufficiently moderate to ensure that green water is taken on board the ship's deck at infrequent intervals only or not at all.
  • Sheltered water. Water where the fetch is six nautical miles or less.

1.4 References

1.4.1 Reference documents
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