Section 1 General

1.1.1 The requirements of this Chapter apply to mobile offshore units fitted with cranes intended for heavy-lift operations and are additional to those applicable in other Parts of the Rules. Crane unit operations include the loading and offloading at quayside, the transportation at sea and the installation and removal offshore of jackets, connecting bridges, topsides, foundations, moorings,transformer substations and other structures. This Chapter is also applicable to crane units equipped to install wind turbines offshore with modified cranes or dedicated handling equipment. Heavy lift cranes are defined in Ch 4, 1.2 Lifting appliances and crane types 1.2.1.(k) of the Code for Lifting Appliances in a Marine Environment, July 2022.

1.1.3 Crane barges and ships may be optionally classed as mobile offshore units, in which case they are to comply with the relevant Parts of these Rules. Alternatively, crane barges and ships may be classed entirely with the Rules and Regulations for the Classification of Ships, July 2022, in which case they are not eligible for the OU and OIWS class notations. The Rules and Regulations for the Classification of Offshore Units, July 2022 provide a higher basis of design for the hull (50-year return period loads and 25-year minimum fatigue life, see Pt 4, Ch 3, 4.1 General 4.1.4.(a) and Pt 4, Ch 5, 5.2 Fatigue life assessment 5.2.3) compared to the Rules and Regulations for the Classification of Ships, July 2022 (20-year return period loads and no required fatigue assessment).

1.1.4 All lifting appliances which form an essential feature of the vessel, are to be classed in accordance with LR’s Code for Lifting Appliances in a Marine Environment, July 2022. Non-essential lifting appliances may be optionally classed (see Table 1.1.1 Special features class notations associated with lifting appliances LR’s Code for Lifting Appliances in a Marine Environment, July 2022). The forces on the lifting appliances due to inclinations and motions of the unit are to be determined by calculation considering all lifting and non-lifting modes of operation. The lifting appliances are to be designed to the most critical loadings and motions.

1.1.5 Pedestal structure which is not part of the hull and not part of the main support structure of the pedestal is to be classed in accordance with LR’s Code for Lifting Appliances in a Marine Environment, July 2022 (see Ch 4, 5 Pedestals and foundations).

1.1.6 Classification of the crane unit will cease to be valid if a significant alteration is made to the classed lifting appliances which form an essential feature or the arrangements on board without the written approval of LR.

1.1.7 Crane units which have a diving complex on board are to have the diving installation approved in accordance with LR’s Rules and Regulations for the Construction & Classification of Submersibles & Diving Systems, July 2022 or a recognised standard acceptable to LR.

1.1.8 Requirements additional to those of this Chapter may be imposed by the National Authority/Coastal State Authority in the country in which the crane unit is registered and/or is to operate, e.g. crane units may require compliance with 2008 SPS Code – Code of Safety for Special Purpose Ships, 2008 – Resolution MSC.266(84) supplemented by the stability requirements of the 2009 MODU Code - Code for the Construction and Equipment of Mobile Offshore Drilling Units, 2009 – Resolution A.1023(26).

1.2.1 Mobile offshore units complying with the requirements of this Chapter and the relevant Parts of these Rules will be eligible for the assignment of the Crane unit class type notation and the special feature class notation LA.

1.2.2 Crane units equipped to install wind turbines offshore which comply with the requirements of this Chapter will be eligible for the assignment of the class type notation MainWIND.

1.2.3 Other special features class notations associated with lifting appliances may be assigned, see Pt 3, Ch 11 Lifting Appliances and Support Arrangements.

1.2.4 Crane units may be assigned additional class type notations when appropriate, see Pt 3, Ch 4, 1.2 Class notations.

1.2.5 Crane units are to have preventive measures to protect personnel from the hazards of dropped objects in accordance with Pt 3, Ch 1, 8 Risks to personnel from dropped objects and are eligible for the class notation DROPS.

1.2.6 Dynamic positioning systems for crane units are to comply with the requirements of Pt 3, Ch 9 Dynamic Positioning Systems and will be eligible for the DP(AA) or DP(AAA) class notation.

1.2.7 Crane units with an oxy-acetylene welding and cutting plant that has been constructed, installed and tested under LR’s Special Survey in accordance with Pt 3, Ch 17, 6 Oxy-acetylene plants for welding and cutting and Pt 1, Ch 3, 22 Oxy-acetylene Welding and Cutting Plants will be eligible for the assignment of the class notation OXY. An oxy-acetylene welding and cutting plant that has not been constructed, installed and tested under LR’s Special Survey is to be certified by LR.

For the purposes of the IMO CSS Code, the objects and equipment carried on decks or in holds by crane units are generally to be considered as cargo.

1.3.3 The hull structure in way of fixed cargo securing fittings is to comply with Pt 3, Ch 14, 4 Ship structure.

1.3.4 Project-specific cargo securing arrangements for crane units are to comply with Pt 3, Ch 18, 1.6 Appraisal of project-specific operations for crane units in service 1.6.1.

1.4.1 In principle, crane units are to be divided into main functional areas to ensure that the following areas are separated and

1.4.2 Attention is to be given to the relevant Statutory Regulations for fire safety of the National Administration in the country of registration and the areas of operation as applicable, see Pt 1, Ch 2, 1 Conditions for classification and Pt 7, Ch 3 Fire Safety.

1.4.3 Areas for crane unit operations are to be located with sufficient access to allow safe cargo securing and handling during installation/connection of equipment, e.g. shackles, lift tools and spreader bars/frames.

1.4.4 Living quarters, lifeboats and other evacuation equipment are to be located in non-hazardous areas and be protected and separated from the areas for crane unit operations. Consideration is to be given to credible accidents resulting from crane unit operations including dropped objects, fire and explosion, spillage and hazardous materials as applicable. See also Pt 4, Ch 3, 4.16 Accidental loads.

1.4.5 Areas where ignition sources may be present, e.g. hot work to weld sea fastenings, are to be located away from areas where flammable vapours may be present, e.g. in the vicinity of fuel tanks.

1.4.6 Additional requirements for safety systems and hazardous areas are given in Pt 7 Safety Systems, Hazardous Areas and Fire.

1.5.1 Plans, calculations and data are to be submitted as required by the relevant Parts of the Rules and LR's Code for Lifting Appliances in a Marine Environment, July 2022 together with the additional plans and information listed in this Chapter.

1.5.2 Details of all intended lifting and non-lifting modes of operation are to be submitted and for each mode of operation to be approved, the operations manual is to include the information required by Pt 3, Ch 1, 3 Operations manual.

1.5.3 Details of pile hammers, pile drills, their power arrangements and any other equipment pertinent to the function of the crane unit are to be submitted.

1.6.1 Project-specific operations for crane units in service, e.g. heavy lifts and cargo securing, should normally be the subject of an engineered assessment by the Owner and be reviewed by a marine warranty surveyor and need not be submitted to LR for approval. However, where it is anticipated that the design limits specified in the operations manual may be exceededor a significant alteration is proposed to be made e.g. to the fixed cargo securing fittings or the cargo securing arrangements, the project-specific assessment is to be submitted to LR for review and the proposed strengthening arrangements, alterations and/or mitigating measures for approval.

1.6.2 Where crane units are deployed in decommissioning, records of hazardous materials brought on board and their subsequent removal are to be kept and made available to the Surveyor.

1.7.1 The minimum design temperature of the crane unit is to be taken in accordance with Pt 3, Ch 1, 4.4 Minimum design temperature. However, the minimum design temperature of the lifting appliances is to be taken in accordance with Code for Lifting Appliances in a Marine Environment, July 2022 Ch 4, 2.25 Materials.