1.3 - Definitions
For the purpose of this Code, unless expressly provided otherwise, the terms used therein have the meanings defined in the following paragraphs.
1.3.1Mobile offshore drilling unit or unit is a vessel capable of engaging in drilling operations for the exploration for or exploitation of resources beneath the sea-bed such as liquid or gaseous: hydrocarbons, sulphur or salt.
1.3.2Surface unit is a unit with a ship or barge-type displacement hull of single or multiple hull construction intended for operation in the floating condition.
1.3.3Self-elevating unit is a unit with moveable legs capable of raising its hull above the surface of the sea.
1.3.4Column stabilized unit is a unit with the main deck connected to the underwater hull or footings by columns or caissons.
- Administration means the Government of the State whose flag the unit is entitled to fly.
- Coastal State means the Government of the State exercising administrative control over the drilling operations of the unit.
1.3.6Organization means the Inter-Governmental Maritime Consultative Organization (IMCO).
1.3.7Certificate means Mobile Offshore Drilling Unit Safety Certificate.
1.3.81974 SOLAS Convention means the International Convention for the Safety of Life at Sea, 1974.
1.3.91966 Load Line Convention means the International Convention on Load Lines, 1966.
1.3.10Mode of operation means a condition or manner in which a unit may operate or function while on location or in transit. The modes of operation of a unit include the following :
- Operating conditions - conditions wherein a unit is on location for the purpose of conducting drilling operations, and combined environmental and operational loadings
are within the appropriate design limits established for such operations. The unit may be either afloat or supported on the sea-bed, as applicable.
- Severe storm conditions - conditions wherein a unit may be subjected to the most severe environmental loadings for which the unit is designed. Drilling 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.
- Transit conditions - conditions wherein a unit is moving from one geographical location to another.
1.3.11Freeboard is the distance measured vertically downwards amidships from the upper edge of the deck line to the upper edge of the related load line.
1.3.12Length (L) means 96 per cent of the total length on a waterline at 85 per cent of the least moulded depth measured from the top of the keel, or the length from the foreside of the stem to the axis of the rudder stock on that waterline, if that be greater. In units designed with a rake of keel the waterline on which this length is measured should be parallel to the designed waterline.
1.3.13Weathertight means that in any sea conditions water will not penetrate into the unit.
1.3.14Normal operational and habitable conditions means:
- conditions under which the unit as a whole, its machinery, services, means and aids ensuring safe navigation when underway, safety when in the industrial mode, fire and flooding safety, internal and external communications and signals, means of escape and winches for rescue boats, as well as the minimum comfortable conditions of habitability are in working order and functioning normally; and
- drilling operations.
1.3.15Gas-tight door is a solid, close-fitting door designed to resist the passage of gas under normal atmospheric conditions.
1.3.16Main source of electrical power is a source intended to supply electrical power for all services necessary for maintaining the unit in normal operational and habitable conditions.
1.3.17Dead ship condition is the condition under which the main propulsion plant, boilers and auxiliaries are not in operation due to the absence of power.
1.3.18Main switchboard is a switchboard directly supplied by the main source of electrical power and intended to distribute electrical energy to the unit's services.
1.3.19Emergency switchboard is a switchboard which in the event of failure of the main system of electrical power supply is directly supplied by the emergency source of electrical power and/or the transitional source of emergency power and intended to distribute electrical energy to the emergency services.
1.3.20Emergency source of electrical power is a source of electrical power intended to supply the necessary services in the event of failure of the main source of electrical power.
1.3.21Main steering gear is the machinery, the steering gear power units, if any, and ancillary equipment and the means of applying torque to the rudder stock, e.g. tiller or quadrant, necessary for effecting movement of the rudder for the purpose of steering the unit under normal service conditions.
1.3.22Auxiliary steering gear is that equipment which is provided for effecting movement of the rudder for the purpose of steering the unit in the event of failure of the main steering gear.
1.3.23Steering gear power unit means, in the case of:
- electric steering gear, an electric motor and its associated electrical equipment:
- electrohydraulic steering gear, an electric motor and its associated electrical equipment and connected pump;
- other hydraulic gear, a driving engine and connected pump.
1.3.24Maximum ahead service speed is the greatest speed which the units is designed to maintain service at sea at its deepest seagoing draught.
1.3.25Maximum astern speed is the speed which it is estimated the unit can attain at the designed maximum astern power at its deepest seagoing draught.
1.3.26Machinery spaces of Category A are all spaces which contain internal combustion type machinery used either:
- for main propulsion; or
- for other purposes where such machinery has in the aggregate a total power of not less than 375 kilowatts, or which contain any oil-fired boiler or oil fuel unit; and trunks to such spaces.
1.3.27Machinery spaces are all machinery spaces of Category A and all other spaces containing propelling machinery, boilers and ocher fired processes, oil fuel units, steam and internal combustion engines, generators and major electrical machinery, oil filling stations, refrigerating, stabilizing, ventilation and air-conditioning machinery and similar spaces; and trunks to such spaces.
1.3.28Control stations are those spaces in which the unit's radio or main navigating equipment or the emergency source of power is located or where the fire recording or fire control equipment or the dynamical positioning control system is centralized. However, in the application of Chapter 9 the space where the emergency source of power is located is not considered as being control station.
1.3.29Hazardous areas are all those areas where, due to the possible presence of a flammable atmosphere arising from the drilling operations, the use without proper consideration of machinery or electrical equipment may lead to fire hazard or explosion.
- Enclosed spaces are spaces delineated by floors, bulkheads and/or decks which may have doors and/or windows.
- Semi-enclosedlocations are locations where natural conditions of ventilation are notably different from those on open decks due to the presence of structures such as roofs, windbreaks and bulkheads and which are so arranged that dispersion of gas may not occur.
1.3.31Industrial machinery and components are the machinery and components which are used in connexion with the drilling operation.
- Non-combustible material means a material which neither burns nor gives off flammable vapours in sufficient quantity for self-ignition when heated to approximately 750°C this being determined to the satisfaction of the Administration by an established test procedure. Any other material is a combustible material.
- A Standard Fire Test is a test as defined in Regulation 3(b) of Chapter II-2 of the 1974 SOLAS Convention.
- "A" Class Divisions are those divisions as defined in Regulation 3(b) of Chapter 11-2 of the 1974 SOLAS Convention.
- "B" Class Divisions are those divisions as defined in Regulation 3(b) of Chapter 11-2 of the 1974 SOLAS Convention.
- "C" Class Divisions are those divisions constructed of non-combustible materials approved by the Administration. They need meet no requirements relative to the passage of smoke and flame or to the limiting of temperature rise.
- Steel or other equivalent material means steel or any material which, by itself or due to insulation provided, has structural and integrity properties equivalent to steel at the end of the applicable fire exposure to the standard fire test (e.g. aluminium alloy with appropriate insulation) .
1.3.33Working spaces are those open or enclosed spaces containing equipment and processes, associated with drilling operations, which are not included in 1.3.27.
1.3.34Accommodation spaces are those used for public spaces, corridors, lavatories, cabins, offices, hospitals. cinemas. games and hobbies rooms, pantries containing no cooking appliances and similar spaces. Public spaces are those portions of the accommodation which are used for halls, dining rooms, lounges and similar permanently enclosed spaces.
1.3.35Service spaces are those used for galleys, pantries containing cooking appliances lockers and store-rooms, workshops other than those forming part of the machinery spaces, and similar spaces and trunks to such spaces.
1.3.36Fuel oil unit is the equipment used for the preparation of oil fuel for delivery to an oil-fired boiler, or equipment used for the preparation for delivery of heated oil to an internal combustion engine, and includes any oil pressure pumps, filters and heaters dealing with oil at a pressure more than 0.18 newtons per square millimetre.
1.3.37Survival craft are craft capable of removing persons from a unit to be abandoned and capable of sustaining persons until retrieval is completed.
1.3.38Rescue boat is an easily manoeuvred power boat capable of rapid launching and adequate for quick recovery of a man overboard and towing a liferaft away from immediate danger.
1.3.39Diving system is the plant and equipment necessary for the safe conduct of diving operations from a mobile offshore drilling unit.