Section 2 Definitions

201. Application

The definitions of terms and symbols which appear in the Rules are to be as specified in this Section, unless otherwise specified, and definitions of terms and symbols not specified in the Rules are to be as specified in Rules for the Classification of Steel Ships and Rules for the Classification of Steel Barges.

202. Length( )

1. For self-elevating units and line, between the insides of

barge type units, length is the distance in metres on the summer load shell platings at the fore and after end.

2. For

column-stabilized units,

length is the maximum distance in metres between the fore and after

end of the primary hull structure which is projected to the centre line of the unit.

3. For

ship type units, length is the distance in metres on the summer load line, from the fore side

of the stem to the centre of the rudder stock, or 96 % of the length on the summer load line, whichever is the greater.

203. Breadth( )

1. For column-stabilized units, breadth is the horizontal distance in metres measured perpendicularly to the longitudinal centre line at the broadest part of the primary hull structure.

2. For self-elevating units, ship type units and barge type units, breadth is the horizontal distance in metres between outside of frames at the broadest part of hull.

Ch 1 General Ch 1

204. Depth( )

1. For column-stabilized units, depth is the vertical distance in metres from the top of bottom plating of the lower hull or footing to the top of beam of the uppermost continuous deck at side measured at the middle of .

2. For self-elevating units, ship type units and barge type units, depth is the vertical distance in me- tres from the top of bottom plating to the top of beam of the uppermost continuous deck at side measured at the middle of .

205. Design water depth

Design water depth is the vertical distance in metres from the sea bed to the mean low water level plus the height of astronomical and storm tides.

206. Light ship weight

Light ship weight is the weight of the complete unit in tons with all its permanently installed ma- chinery, equipment and outfit, including permanent ballast, spare parts normally retained on board, and liquids in machinery and piping to their normal working levels, but does not include cargo, liquid in storage or reserve supply tanks, items of consumable or variable loads, any allowance for stores, or crew and their effects.

207. Modes of operation

A mode of operation is a condition or manner in which a unit may operate or function while on location or in transit. In the application of the Rules, the approved modes of operation of a unit are defined as follows.

(1) Operating condition : Operating condition is a condition wherein a unit is on location for the purposes of operations, and combined environmental and operational loadings are within the ap- propriate design limits established for such operations. The unit may be either afloat or sup- ported on the sea bed, as applicable.

(2) Severe storm condition : Severe storm condition is a condition during which a unit may be subjected to the severest environmental loadings for which the unit is designed. Operations are assumed to have been discontinued due to the severity of the environmental loadings. The unit may be either afloat or supported on the sea bed, as applicable.

(3) Transit condition : Transit condition is a condition wherein a unit is moving from graphical location to another without any operation of its purpose.

(4) Temporary mooring condition : Temporary mooring condition is a condition wherein

temporarily moored in the afloat condition.

one geo- a unit is

208. Non-self-propelled unit

Non-self-propelled unit is the unit which has no propulsion machinery or designed to be towed or pushed by other ships when the unit voyages through the ocean normally even if the unit has pro- pulsion machinery.

209. Self-propelled unit

Self-propelled unit is the unit other than non-self-propelled unit.

210. Working area

Working spaces are those open or enclosed spaces containing equipment and processes, associated with drilling operations, which are not included in hazardous areas and machinery spaces.

211. Control station

Control stations are those spaces in which the ships radio equipment, main navigation equipment or emergency source of power is located and control panels for posture or position control equipment, leg elevation control equipment, central ballast control devices, central fire detection central fire alarm devices are installed.

212. Down flooding

Down flooding means any flooding of the interior or any part of the buoyant structure of a unit through openings which cannot be closed weathertight, watertight or which are required for opera- tional reasons to be left open in all weather conditions, as appropriate for the intact and damage stability criteria.

213. Weathertight

Weathertight means that in any sea conditions water will not penetrate into the unit.

214. Watertight

Watertight means that capability of preventing the passage of water through structure in any direc- tion under the head of water for which the surrounding structure is designed.

215. Moulded draught

The moulded draught is the vertical distance in metres measured from the moulded base line to the assigned load line. Certain components of a unit's structure, machinery or equipment may extend below the moulded base line.

216. Moulded base line

The moulded base line is a horizontal line extending through the upper surface of the bottom plating.

217. Drilling system

Drilling systems are entire machinery and systems used in drilling well and producing petroleum.