Section 5 Load lines

5.1.1 Any unit to which a load line is required to be assigned under the applicable terms of the Load Line Convention is to be subject to compliance with the Convention, see Pt 4, Ch 7, 1.1 Application 1.1.2. For semi-submersible and self-elevating units, see also Pt 4, Ch 7, 5.2 Column-stabilised units and tension-leg units and Pt 4, Ch 7, 5.3 Self-elevating units respectively.

5.1.2 The requirements of the Load Line Convention, with respect to weathertightness and watertightness of decks, superstructures, deckhouses, doors, hatchway covers, other openings, ventilators, air pipes, scuppers, inlets and discharges, etc. are taken as a basis for all units in the afloat conditions.

5.1.3 The requirements for hatchways, doors and ventilators are dependent upon the position on the unit as defined in Pt 4, Ch 7, 2.5 Position 1 and Position 2.

5.1.4 Units which cannot have freeboard computed by normal methods laid down by the Load Line Convention will have the permissible draughts determined on the basis of meeting the applicable intact stability, damage stability and structural requirements for transit and operating conditions while afloat. In no case is the draught to exceed that permitted by the Load Line Convention, where applicable.

5.1.5 All units are to have load line marks which designate the maximum permissible draught when the unit is in the afloat condition. Such markings are to be placed at suitable visible locations on the structure, to the satisfaction of LR. These marks, where practicable, are to be visible to the person in charge of mooring, lowering or otherwise operating the unit.

5.2.2 The conditions of assignment are to be based on the requirements of the Load Line Convention. The Regulations of the relevant National Administration are also to be complied with, see Pt 4, Ch 7, 1.1 Application 1.1.2.

5.2.3 In general, the heights of hatch and ventilator coamings, air pipes, door sills, etc. in exposed positions and all closing appliances are to be determined by consideration of both intact and damage stability requirements.

5.2.4 The freeboard deck and reference deck from which the air gap is measured, is normally taken as the lowest continuous deck exposed to weather and sea, and which has permanent means of closing and below which all openings are watertight and permanently closed at sea.

5.2.5 Side scuttles and windows, including those of non-opening type, or other similar openings, are not to be fitted below the freeboard deck, as defined inPt 4, Ch 7, 5.2 Column-stabilised units and tension-leg units 5.2.4.

5.2.6 In addition to the stability requirements in Pt 4, Ch 7, 4.7 Weathertight integrity related to stability, the upper deck and the boundaries of the enclosed upper hull structure between the upper deck and the freeboard deck are to be made weathertight.

5.2.7 Special consideration will be given to the position of openings which cannot be closed in emergencies, such as air intakes for emergency generators.

5.3.1 Load lines and conditions of assignment for self-elevating units when afloat in transit conditions will be subject to the applicable terms of the Load Line Convention. A load line, where assigned, is not applicable to self-elevating units when resting on the sea bed, or when lowering to or raising from such position. The Regulations of the relevant National Administration are also to be complied with, see Pt 4, Ch 7, 1.1 Application 1.1.2.

5.3.2 Special consideration is to be given to the freeboard of units with moonpools or drilling wells extending through the main hull structure.

5.3.3 In general, the heights of hatch and ventilator coamings, air pipes, door sills, etc. in exposed positions and all closing appliances are also to be determined by consideration of both intact and damage stability requirements.

5.4.1 Ship units and surface type units are to comply with the requirements of Pt 4, Ch 7, 5.1 General 5.1.1. Special consideration is to be given to the freeboard of units with moonpools or drilling wells extending through the main hull structure.

5.5.1 When afloat in transit conditions, sea bed-stabilised units are to comply with the requirements of Pt 4, Ch 7, 5.2 Column-stabilised units and tension-leg units and Pt 4, Ch 7, 5.3 Self-elevating units as applicable.

5.6.1 The weathertight integrity of units which are not subject to the requirements of the Load Line Convention will be specially considered on the basis of Pt 4, Ch 7, 5.7 Weathertight integrity and the requirements for both intact and damage stability. See also Pt 4, Ch 7, 1.1 Application.

5.7.1 Closing arrangements for shell, deck and bulkhead openings and the requirements for ventilators, air pipes and overboard discharges, etc. are to comply with Pt 4, Ch 7, 6 Miscellaneous openings to Pt 4, Ch 7, 10 Scuppers and sanitary discharges.

5.7.2 The requirements of this Chapter conform, where relevant, with those of the Load Line Convention. Reference should also be made to any additional requirements of the National Authority of the country in which the unit is to be registered and to the appropriate Regulations of the Coastal State Authority in the area where the unit is to operate.

5.7.3 The closing appliances are, in general, to have a strength at least corresponding to the required strength of that part of the hull in which they are fitted.

5.7.4 The requirements for closing appliances of hatches, doors, ventilators, air pipes, etc. and their associated coamings, situated at such a height as will not constitute a danger to the weathertightness of the unit, will be specially considered.

5.7.5 In all areas where mechanical damage is likely, all air and sounding pipes, scuppers and discharges, including their valves, controls and indicators, are to be well protected. This protection is to be of steel or other equivalent material.