Section 1 Conditions for classification
Clasification Society 2024 - Version 9.40
Clasifications Register Rules and Regulations - Rules and Regulations for the Classification of Offshore Units, July 2022 - Part 1 Regulations - Chapter 2 Classification Regulations - Section 1 Conditions for classification

Section 1 Conditions for classification

1.1 Application

1.1.1 The Rules and Regulations for the Classification of Offshore Units (hereinafter referred to as the Rules for Offshore Units) are applicable to units engaged in offshore operations including drilling, oil/gas production and storage, accommodation and other support functions and which generally operate within the territorial waters of a Coastal State Authority but excluding the ship types defined in Part 4 of the Rules and Regulations for the Classification of Ships.

1.1.2 An offshore unit may be assigned one of the two following class notations:

OI

This notation is applicable to floating offshore installations that operate at a fixed geographic location for their entire service life, see Pt 1, Ch 2, 1.2 Floating offshore installations at a fixed location.

The following asset types are covered by the OI notation:
  • column-stabilised semi-submersible floating production units (FPU);
  • self-elevating (jack-up) production units;
  • jack up accommodation
  • crude oil floating production, storage and offloading ship and barge type units;
  • crude oil floating storage and offloading ship and barge type units;
  • liquefied gas floating production and storage ship and barge type units;
  • liquefied gas floating storage ship and barge type units;
  • tension leg units;
  • deep draught caisson units;
  • buoys;
  • floating offshore sea-water desalination units.

OU

This notation is applicable to mobile offshore units that operate at and transit between different locations, see Pt 1, Ch 2, 1.3 Mobile offshore units.

The following asset types are covered by the OU notation:
  • column-stabilised semi-submersible units (mobile offshore drilling units, heavy lift vessels, pipe-laying units, accommodation units and diving support vessels);
  • self-elevating (jack-up) mobile offshore drilling units;
  • surface type units (drill ships, twin-hull heavy lift vessels and pipe-laying units);
  • wind turbine installation vessels;
  • tender barge.
1.1.3 The following Parts, Chapters and Sections are only applicable to mobile offshore units:
1.1.4 The basic Lloyd’s Register (LR) class notation for an installation would normally include:
  • Description of the installation, facilities provided and field location.
  • Structure and marine systems.
  • Positional mooring system.
  • Propulsion (where applicable).

1.1.5 The notation PPF (Process Plant Facility) can be assigned to process facilities on production and oil storage units – see Pt 1, Ch 2, 2.4 Class notations (hull/structure) 2.4.13. These process facilities will be installed on a unit with a LR classed hull, classed marine systems and a classed mooring system.

1.1.6 If the process facilities are not requested to be classed (no PPF notation), classification of the unit will be subject to alternative applicable international Codes and Standards considered by LR as an equivalent level of safety to Rule requirements. These process facilities will be installed on a unit with a LR classed hull, classed marine systems and a classed mooring system.

1.1.7 Whether the PPF notation is assigned or not, the process facilities will require to be surveyed or verified throughout the unit’s service life to maintain classification.
  1. The process plant facilities include the equipment, supporting structure and systems used for oil and gas production.
1.1.8 As an option, the Owner may request that LR consider performance standards determined by risk assessment as the basis for design, construction, and inspection/ maintenance. Guidelines for classification of an offshore installation using risk assessment to determine performance standards are provided in Pt 1, Ch 5 Guidelines for Classification using Risk Assessment Techniques to Determine Performance Standards. Definitions of risk assessment terms are also given in Chapter 5. Performance standards determined by risk assessment may be accepted by LR as the alternative basis for classification, provided that:

Where a Formal Safety Assessment or Safety Case is prepared as a requirement of a National Administration or of the Owner, the Owner may request that LR consider the results as a basis for determining the performance standards to be used for classification. In such cases, the Formal Safety Assessment or Safety Case will be reviewed by LR to confirm that it considers all hazards to the safety and integrity of the installation which are relevant to classification. The Guidelines in Pt 1, Ch 5 Guidelines for Classification using Risk Assessment Techniques to Determine Performance Standards will then apply.

1.1.9 For units which are outside the scope of application of the 2009 MODU Code - Code for the Construction and Equipment of Mobile Offshore Drilling Units, 2009 – Resolution A.1023(26) and/or the international conventions referred to in Pt 1, Ch 2, 1.4 General 1.4.10, compliance with any prescribed standards of the applicable Coastal State Authority is to be demonstrated by the issue of appropriate certification by that Coastal State Authority or LR where so authorised.

1.2 Floating offshore installations at a fixed location

1.2.1 Floating offshore installations at a fixed location will be assigned the class notation OI.

1.2.2 LR classed tankers being converted for service as a floating offshore installation at a fixed location in accordance with the requirements of these Rules will be eligible for class notation OI. Special consideration will be given to the class notation assigned when the tanker to be converted is not classed with LR, see also Pt 10 Ship Units.

1.3 Mobile offshore units

1.3.1 Mobile offshore units will be assigned the class notation OU.

1.3.2 The adequacy of sea bed conditions with respect to bearing capacity, resistance to possible sliding and anchor holding capacity is not covered by classification. In particular, for self-elevating units, it is the responsibility of the Owner to be satisfied that the sea bed conditions are suitable to allow the legs to be safely and adequately preloaded.

1.3.3 It is the Owner’s responsibility to comply with any applicable regulations of the Coastal State Authorities in the areas of operation. Compliance with the prescribed standards of the applicable National Administration is to be demonstrated by the issue of appropriate certification by the National Administration or LR where so authorised. See also Pt 1, Ch 2, 1.4 General 1.4.11.

1.3.4 to operate for prolonged periods adjacent to other offshore installations which are being used for hydrocarbon exploration or production, it is the Owner’s responsibility to comply with the requirements of the appropriate National Administration and LR is to be advised at the approval stage so that classification aspects relating to safety are taken into account, see Pt 7 Safety Systems, Hazardous Areas and Fire. Special consideration will be given to existing units with regard to class.

1.4 General

1.4.1 Offshore units built in accordance with LR’s Rules and Regulations, or in accordance with requirements equivalent thereto, will be assigned a class on the Class Direct website and will continue to be classed so long as they are found, upon examination at the prescribed surveys, to be maintained in accordance with the requirements of the Rules. Classification will be conditional upon compliance with LR’s requirements for materials, structure, machinery, equipment and other safety considerations.

1.4.2 Units designed and constructed to standards other than the Rule requirements will be considered for classification, subject to the alternative standards being considered by LR to give an equivalent level of safety to the Rule requirements. It is essential that in such cases LR is informed of the Owner’s proposals at an early stage, in order that a basis for acceptance of the standards may be agreed.

1.4.3 The Classification Committee, in addition to requiring compliance with LR’s Rules, or other agreed performance standards, may require to be satisfied that units are suitable for geographical or other limits or conditions of the service contemplated.

1.4.4 Although the specified design environmental criteria on which classification is based are the responsibility of the Owner, assessment by LR of a unit’s suitability for service at a particular offshore location will be undertaken and agreed before approval.

1.4.5 Loading conditions and other preparations required to permit a unit (whether self-propelled or not) with a notation specifying some service limitation to undertake a sea-going voyage, either from port of building to service area or from one service area to another, are to be in accordance with arrangements agreed by LR prior to the voyage.

1.4.6 Any damage, defect, breakdown or grounding, serious deficiency, detention or arrest, or refusal of access which could invalidate the conditions for which class has been assigned is to be reported to LR without delay.

1.4.7 The Owner is solely responsible for the operation of the unit. The Rules are framed on the understanding that the unit will be properly loaded and operated, and the environmental conditions are no more severe than those agreed for the design basis and approval, without prior agreement of LR.

1.4.8 When longitudinal strength calculations are required for ship units and other surface type units, loading guidance information is to be supplied to the Master by means of a Loading Manual and in addition, when required, by means of a loading instrument, see also Pt 1, Ch 2, 1.4 General 1.4.9. Loading Manuals and loading instruments for surface type units are to be in accordance with Pt 4, Ch 4, 8 Transport and handling of hazardous and noxious liquid substances in bulk of the Rules for Ships.

1.4.9 It will be the responsibility of the Owner to provide instructions and set down limits for the operation of the unit to ensure that the loading and environmental conditions on which classification is based will not be exceeded. These instructions and limitations are to be contained in the Operations Manual (or a Loading Manual for ship units and other surface type units) which is to be retained on board the unit. The Owner should ensure that the Manual is kept up to date and contains appropriate data required by the relevant National Administration.

The Classification Committee requires the applicable Convention and Code Certificates to be issued by authorities as follows:
  • Cargo Ship Radio Certificates, Safety Management Certificates, International Ship Security Certificates and Maritime Labour Certificates, if required, must have been issued by a recognised organisation authorised by the National Administration with which the unit is registered.
  • All other mandatory statutory certificates must have been issued by LR or by a National Administration or by an IACS Member when so authorised by the National Administration with which the unit is registered.

In the case of dual-classed units, Convention Certificates may be issued by the other Classification Society with which the unit is classed, provided this is recognised in a formal Dual Class Agreement with LR and provided the other Classification Society is also authorised by the National Administration.

In the event of a National Administration withdrawing any unit’s Convention Certificate (referred to in this Section), then the Classification Committee may suspend the unit’s class. If a unit is removed from the National Administration’s Registry for the non-compliance with the Conventions or Classification Requirements referred to herein, then the Classification Committee will suspend the unit’s class. In the event of ISM Code certification being withdrawn from a unit or Operator, then the Classification Committee will suspend the unit’s class.

1.4.11 Where the National Administration has no prescribed standards for units which are outside the scope of application of the 2009 MODU Code - Code for the Construction and Equipment of Mobile Offshore Drilling Units, 2009 – Resolution A.1023(26) and/or the International Conventions referred to in Pt 1, Ch 2, 1.4 General 1.4.10 or their standards are not considered acceptable for classification purposes, LR will apply the relevant parts of the 2009 MODU Code - Code for the Construction and Equipment of Mobile Offshore Drilling Units, 2009 – Resolution A.1023(26)/Convention Regulations and other recognised Standards as applicable to the intended use of the unit as a prerequisite to classification.

1.4.12 Where an onboard computer system having longitudinal strength computation capability, which is required by the Rules, is provided on a new unit or newly installed on an existing unit, then the system is to be certified in respect of longitudinal strength in accordance with LR’s Approval of Longitudinal Strength and Stability Calculation Programs.

1.4.13 Where an onboard computer system having stability computation capability is provided on a new unit, the system is to be certified in respect of stability aspects, in accordance with LR’s Approval of Longitudinal Strength and Stability Calculation Programs. When provided, an onboard computer system having stability computation capability is to carry out the calculations and checks necessary to assess compliance with all the stability requirements applicable to the unit on which it is installed.

1.4.14 When a unit, fitted with a conventional rudder, is to operate for a prolonged period at a fixed location, it is the Owner’s responsibility to ensure that suitable arrangements are provided to prevent damage to the steering gear. Special consideration will be given to the requirements for the steering gear and propelling machinery, see Pt 4, Ch 10 Steering and Control Systems, and Pt 5, Ch 6 Main Propulsion Shafting and Pt 5, Ch 19 Steering Gear.

1.4.15 Where a unit has been detained by Port State Control, the Owner is to advise LR immediately, in order to arrange the attendance of a Surveyor.

1.5 Interpretation of the Rules

1.5.1 The interpretation of the Rules is the sole responsibility, and is at the sole discretion, of LR. Any uncertainty in the meaning of the Rules is to be referred to LR for clarification.

1.5.2 In many instances, these Rules require that particular components, systems and equipment, etc., must also comply with applicable Sections of the Rules for Ships. Every effort has been made to avoid potential conflicting requirements; however, where such a conflict becomes apparent, the requirements of these Rules shall take precedence.

1.6 Advisory services

1.6.1 The Rules do not cover certain technical characteristics, such as stability, hull vibration, etc., but advice may be given on such matters without any assumption of responsibility for such advice.

1.7 Legislative verification

1.7.1 LR has been authorised by a number of National Administrations to carry out verification of offshore units and installations in accordance with statutory Regulations. Full details will be supplied to Owners and other interested parties on request. See also Pt 1, Ch 2, 2.8 Class notation (Verification Schemes) and Pt 1, Ch 4 Verification in Accordance with National Regulations for Offshore Installations.

1.7.2 LR has also been authorised on behalf of National Administrations of a large number of nations to issue certain statutory, safety and other certificates. LR is willing to act, when requested, in respect of such certification.

1.7.3 When machinery and equipment are to comply with EC Directives, LR as a notified body can issue EC Type Certification in accordance with LR’s appointment. Full details will be supplied to manufacturers and other interested parties on request.


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