Section 2 Machinery Installations

201. Engines, shaftings and power transmission gears

1. Internal combustion engines

(1) General construction, safety devices, installation, exhaust arrangements and fuel oil arrangements of internal combustion engines are to be in accordance with the requirements in Pt 5, Ch 2, Sec 2 and Ch 6, Sec 6 and 9 of Rules for the Classification of Steel Ships respectively. However, the requirement in Pt 5, Ch 2, 203. 10 of Rules for the Classification of Steel Ships for alarming devices of lubricating oil supply is only applied for engines for the main source of electrical power and for engines for the power plant of jacking systems.

(2) Internal combustion engines used for the systems essential for the safety of the units are to be

in accordance with the requirements in Pt 5, Ch Steel Ships.

2. Steam turbines

2, Sec 2 of Rules for the Classification of

(1) Steam turbines are to be provided with overspeed protective devices to prevent the design speed from being exceeded by more than 115 %.

(2) Steam turbines used for the systems essential for the safety of the units are to be in accordance with the requirements in Pt 5, Ch 2, Sec 3 of Rules for the Classification of Steel Ships.

3. Gas turbines

Gas turbines are to be in accordance with the requirements in Pt 5, Ch 2, Sec 4 of Rules for the Classification of Steel Ships.

4. Stern bearings and sealings of propeller shafts

Where the units with propulsion machinery are impractical to dock, the units are to be designed to enable the measurement of weardown of the stern bearings and the inspection and repair of bear- ings and sealings in a floating condition.

5. Power transmission gears

All gearing, shafts and couplings used for transmission of power to machinery are to be designed and constructed so that they will withstand the maximum working stresses to which they may be subjected in all service conditions, taking into account the type of engines by which they are driv- en or of which they form part.

202. Boilers and pressure vessels

Boilers and pressure vessels are to be in accordance with the requirements in Pt 5, Ch 5 of

Rules for the Classification of Steel Ships.

203. Auxiliaries and piping arrangements

1. General

(1) Auxiliaries and piping arrangements are to be in accordance with the requirements in this Article as well as those in Pt 5, Ch 6 of Rules for the Classification of Steel Ships.

(2) Pipes are to be arranged inboard of the zone of assumed damage penetration in Ch 7, 104. un-

less special consideration has been taken in the damage stability review.

(3) Where valves of piping systems are arranged for remote control and are power-operated, a sec- ondary means of operating the valves which may be manually controlled, is to be provided.

(4) Piping systems carrying non-hazardous fluids are generally to be separated from piping systems which may contain hazardous fluids. Cross connection of the piping systems may be permitted where means for avoiding possible contamination of the non-hazardous fluid system by the haz- ardous medium are provided.

(5) Piping systems used for the safe operation of the unit are generally to be separate from those

used solely for drilling operations. However, consideration will be taken in the connection of the two piping systems, if necessarily accepted by the Society.

(6) To prevent ignition, exhaust pipe insulation is to be encased in steel sheathing or equivalent

material to be protected against possible oil absorption.

2. Feed water systems and fuel oil burning systems for boilers

For boilers intended to supply steam for other than the systems or the equipment for the safety of the unit and for the propulsion of the unit (only applicable to the unit which has the main pro-

pulsion machinery), only one feed water piping and pump

and fuel

oil burning system for boilers

may be acceptable notwithstanding the requirements in Pt

the Classification of Steel Ships.

5, Ch 6, Sec 5 and 6 of Rules for

3. Arrangements for oil fuel, lubricating oil and other flammable oils

(1) Arrangements

for the storage, distribution and utilization of oil fuel and pressurized lubricating

oil should be such as to ensure the safety of the unit and persons on board.

(2) Arrangements for the storage, distribution and utilization of other flammable oils employed under pressure in power transmission systems, control and activating systems and heat transfer systems

should be such as to ensure the safety of the unit and persons on board.

(3) In machinery spaces pipes, fittings and valves carrying flammable oils should be of a material approved by the Society, having regard to the risk of fire.

(4) Location and arrangement of vent pipes for fuel oil service, settling and lubrication oil tanks should be such that, in the event of a broken vent pipe, the risk of ingress of rainwater or sea-

water is minimized.

(5) Two fuel oil service tanks for each type of fuel used on board necessary for propulsion and vi- tal systems or equivalent arrangements are to be provided with a capacity of at least 8 hours at maximum continuous rating of the propulsion plant and normal operating load at sea of the generating plant and the boiler.

(6) High pressure fuel delivery lines

(A) All external high pressure fuel delivery lines between the high pressure fuel pumps and fuel

injectors should be protected with a jacketed piping system capable of containing fuel from a high pressure line failure. A jacketed pipe incorporates an outer pipe into which the high pressure fuel pipe is placed forming a permanent assembly. The jacketed piping system should include a means for collection of leakages and arrangements should be provided for an alarm to be given of a fuel line failure.

(B) All surfaces with temperatures above 220°C, which may be impinged as a result of a fuel system failure, should be properly insulated.

(C) Oil fuel lines should be screened or otherwise suitably protected to avoid, as far as practi- cable, oil spray or oil leakages onto hot surfaces, into machinery air intakes, or other sour-

ces of ignition. The number of joints in such piping systems should be kept to a minimum.

4. Compressed air systems

(1) In every unit means should be provided to prevent excess pressure in any part of compressed air systems and where water jackets or casings of air compressors and coolers might be sub- jected to dangerous excess pressure due to leakage into them from air pressure parts. Suitable pressure relief arrangements should be provided for all systems.

(2) The starting air arrangements for internal combustion engines should be adequately protected against the effects of backfiring and internal explosions in the starting air pipes.

(3) Starting air pipes from the air receivers to internal combustion engines should be entirely sepa- rate from the compressor discharge pipe system.

(4) Provision should be made to reduce to a minimum the entry of oil into the starting air pressure systems and to drain these systems.

5. Bilge systems

(1) An efficient bilge pumping system should be provided, capable of pumping from and draining

watertight compartments other and for which other efficient whether the unit is upright or

than spaces permanently appropriated for the carriage of liquid means of pumping are provided, under all practical conditions inclined, as specified in 103. Additional suctions should be pro-

vided in large compartments or compartments of unusual form, as deemed necessary by the Society. In addition to bilge piping arrangements required by (12) below, means are to be pro-

vided to detect the presence of water in such compartments which are

adjacent to the sea or

adjacent to tanks containing liquids and in void compartments through which pipes conveying liquids pass. If the Society is satisfied that the safety of the unit is not impaired, the means to detect the presence of water may be dispensed with

(2) Emergency bilge suctions may be dispensed with notwithstanding the requirements in Pt 5, Ch 6, 403. 6 of Rules for the Classification of Steel Ships.

(3) For units subject to the requirements in this Section, the requirements for the direct bilge suc-

tions prescribed in Pt 5, Ch 6, Sec 4 of Rules for the Classification of Steel Ships are only applied for compartments under the load line containing the main source of electric power. Where, however, these compartments are pumped up by exclusive bilge pumps, the direct bilge suctions may be dispensed with.

(4) Notwithstanding the requirements in Pt 5, Ch 6, Sec 4 of Rules for the Classification of Steel Ships, in determination of the internal diameters of the main bilge line and the branch bilge suctions, the following requirements are to be complied:

(A) Branch bilge suction pipes from each compartment are to be of the internal diameter ob- tained from the following formula or the standard pipes of internal diameter nearest to the calculated diameter. In case where the internal diameter of such standard pipes is short of the calculated value by 5 mm or more, standard pipes of one grade higher diameter are to be used. The internal diameter of any bilge line is not to be less than 50 mm .

mm

where :

:

(B) The cross

Internal diameters of the branch bilge suctions (mm ).

Wetted surface of the compartment, excluding stiffening members when the com- partment is half filled with water (m ).

sectional area of the main bilge line is not to be less than the combined areas

of the two largest branch suctions.

(5) The capacity, , of each bilge pumping unit or bilge pump is not to be less than that required by the following formula.

m

where:

= Required internal diameter of main bilge line (mm )

(6) Taking account of purposes and operating mode of the units, the Society may accept one bilge pump notwithstanding the requirements in Pt 5, Ch 6, Sec 4 of Rules for the Classification of Steel Ships.

(7) The following additional provisions are applicable to column-stabilized units:

(A) Chain lockers which, if flooded, could substantially affect the unit’s stability should be pro- vided with a remote means to detect flooding and a permanently installed means of

dewatering. Remote indication of flooding should be provided at the central ballast control

station.

(B) At least one of the pumps referred to in Subparagraph (8) and pump-room bilge suction valves should be capable of both remote and local operation.

(C) Propulsion rooms and pumprooms in lower hulls should be provided with two independent

systems for high bilge water level detection providing an audible and visual alarm at the central ballast control station.

(8) At least two self-priming power pumps connected to each bilge main should be provided.

Sanitary, ballast and general service pumps may be accepted as independent power bilge pumps

if fitted with

the necessary connections to the bilge pumping system. Ejectors and their asso-

ciated pumps

considered as

which power

are so arranged as to bilge pumps according

be capable of discharging bilge to the requirement in Pt 5, Ch

effectively will be

6, Sec 4, 405. 1

(3) of Rules for the Classification of Steel Ships.

(9) Compartments below deck containing essential equipment for operation and safety of the unit are to have a permanently installed bilge or drainage system. These compartments are to be

drained with at least two bilge pumps, or equal.

(10) All distribution boxes and manually operated valves in connection with the bilge pumping ar- rangements are to be in positions which are accessible under normal circumstances. Where such

valves are located in normally unmanned spaces below the assigned load line and not provided with high bilge water level alarms, they are to be operable from outside the spaces.

(11) Chain lockers are to be capable of being drained by a permanently installed bilge or drainage

system or by portable means. Means are to be provided for removal of mud and debris from the bilge or drainage system.

(12) Void compartments adjacent to the sea or to tanks containing liquids, and void compartments

through which piping conveying liquids passes, are to be drained by permanently installed bilge or drainage systems or by portable means. If portable pumps are used, two are to be provided and both pumps and arrangements for pumping are to be readily accessible. Void compartments as defined above which are not provided with bilge or drainage systems in compliance with the above are to be accounted for the stability analysis in the unit.

(13) Drainage of hazardous areas should be given special consideration having regard to the risk of

explosion. Hazardous and non-hazardous areas are to be provided with separate drainage or pumping arrangements.

(14) A means to indicate whether a valve is open or closed is to be provided at each location

from which the valve can be controlled. The indicator is to rely on movement of the valve spindle.

(15) All bilge pipes should be of steel or other suitable material having properties acceptable to the

Administration. Special consideration should be given to the design of bilge lines passing through ballast tanks taking into account effects of corrosion or other deterioration.

(16) The arrangement of the bilge pumping system should be such as to prevent the possibility of

water passing from the sea into dry spaces, or inadvertently from one compartment to another.

6. Ballast systems for column-stabilized units

(1) Units are to be provided with an efficient pumping system capable of ballasting and deballasting any ballast tank under normal operating and transit conditions.

(2) The system is to be capable of raising the unit, starting from a level trim condition at the deepest normal operating draft, to the severe storm draft, or a greater distance as may be speci-

fied by the Society, within three hours.

(3) For column-stabilized units, the ballast systems are to consist of two or more adequate means by way of pumps or other suitable apparatuses, and they are to be capable of ballasting and de-ballasting all compartments even when one of them is out of service. The ballast pumps are to be of the self-priming type or be provided with a separate priming system.

(4) The ballast system should be capable of operating after the damage specified in Ch 4, Sec 5

and have the capability of restoring the unit to a level trim and safe draught condition without

taking on additional ballast, with any one pump inoperable. The Society may permit counter- flooding as an operational procedure. Counter-flooding is not to be considered as a means to improve the suction head available to the ballast pumps when considering the operability of the ballast system after the damage specified in Ch 4, Sec 5.

(5) The ballast system is to be arranged to prevent the inadvertent transfer of ballast water from one quadrant to any other quadrant of the unit. The system is also to be arranged so that the transfer of ballast water from one tank to any other tank through a single valve is not possible except where such a transfer could not adversely affect the stability of the unit.

(6) It is to be possible to supply each ballast pump required by Subparagraph (3) above from the

emergency source of electrical power. The arrangements are to be such that the system is capa- ble of restoring the unit from an inclination specified in 103. to a level trim and safe draught condition after loss of any single component in the power supply system.

(7) All ballast pipes should be of steel or other suitable material having properties acceptable to the Society. Special consideration should be given to the design of ballast lines passing through bal- last tanks, taking into account effects of corrosion or other deterioration.

(8) All valves and valve control systems for their function are to be clearly marked. A means to indicate whether a valve is open or closed is to be provided at each location from which the valve can be controlled. The indicator is to rely on movement of the valve spindle.

(9) Air pipes should be provided on each ballast tank sufficient in number and cross-sectional area to permit the efficient operation of the ballast pumping system under the conditions referred to in Subparagraphs (1) to (8).

(10) Sounding devices of approved type are to be provided in

the ballast tanks in the lower hulls

of the column-stabilized units. However, for the units to be used at both the high and low pre-

determined ballast water levels, the sounding devices may

be substituted by alarming devices

which will alarm at either of these levels.

(11) A central ballast control station should be provided. It should be located above the worst dam- age waterline and in a space not within the assumed extent of damage referred to in Ch 4 and adequately protected from weather. It should be provided with the following control and indicat- ing systems, having appropriate audible and visual alarms, where applicable:

(A) ballast pump control system

(B) ballast pump status-indicating system

(C) ballast valve control system

(D) ballast

valve position-indicating system

(E) tank level indicating system

(F) draught indicating system

(G) heel and trim indicators

(H) power availability indicating system (main and emergency)

(I) ballast system hydraulic/pneumatic pressure-indicating system.

(12) In addition to remote control of the ballast pumps and valves from the central ballast control

station, all ballast pumps and valves should be fitted with independent local control operable in the event of remote control failure. The independent local control of each ballast pump and of its associated ballast tank valves should be in the same location.

(13) The control and indicating systems listed in Subparagraph (11) above should function in- dependently of one another, or have sufficient redundancy, such that a failure in one system does not jeopardize the operation of any of the other systems.

(14) Each power-actuated valve is to fail to the closed position upon loss of control power. Upon

reactivation of control power, each such valve is to remain closed until the reactivation of system is assumed. The Society may accept ballast valve arrangements that do not fail to

closed position upon loss of power provided that the Society is satisfied that the safety of unit is not impaired.

the the

the

(15) The ballast tank level indicating system required by Subparagraph (11) above is to provide means specified in the following (A) and (B).

(A) A means to indicate liquid levels in all ballast tanks. A secondary means of determining

levels in ballast tanks, which may be a sounding pipe, should be provided. Tank level sen- sors should not be situated in the tank suction lines;.

(B) A means to indicate liquid levels in tanks which, in view of the Society, could affect the stability of the unit. Tank level sensors are not to be situated in the tank suction lines.

(16) The draught indicating system required by Subparagraph (11) above is to indicate the draught at each corner of the unit or at representative positions as deemed appropriate by the Society.

(17) Enclosures housing ballast system electrical components, the failure of which would cause un-

safe operation of the ballast system upon liquid entry into the enclosure, should comply with

Ch 6, 203. 21.

(18) A means is to be provided at the central ballast control station to isolate or disconnect the ballast pump control and ballast valve control systems from their sources of electrical, pneumatic

or hydraulic power.

(19) A permanently installed means of communication, independent of the unit’s main source of electrical power, should be provided between the central ballast control station and spaces that

contain ballast pumps or valves, or other spaces that may contain equipment necessary for the

operation of the ballast system.

7. Air pipes and sounding pipes

(1) Air pipe openings and discharge openings of overflow pipes are to be located above the final

calculated

immersion line in the assumed damage condition specified in Ch 7, and are to be

positioned outside the extent of damage, as defined in Ch 7.

(2) Air pipes

and overflow pipes which could cause progressive flooding are to be considered in

the damage stability review.

(3) Where the air pipes or sounding pipes for the ballast tanks in the lower hulls of the col- umn-stabilized units are exposed to sea water under the load water line, these pipes are to have sufficient thickness against corrosion and to be protected from mechanical damage or to have sufficient strength.

(4) One air pipe may be acceptable for certain tanks notwithstanding the requirements in Pt 5, Ch 6, Sec 2 of Rules for the Classification of Steel Ships provided that the Society consid- ered satisfactory taking account of the types and service conditions of the units.

(5) All tanks are to be provided with separate sounding pipes, or approved remote level indicating system. Where a sounding pipe exceeds 20 m in length, the minimum internal diameter is to be at least 50 mm notwithstanding the requirements in Pt 5, Ch 6, 203. 3 (3) of Rules for the Classification of Steel Ships.

Sounding pipes are to be of the minimum internal diameter 38 mm . Where a sounding pipe ex- ceeds 20 m in length, the minimum internal diameter is to be increased to at least 50 mm .

(6) Where a remote level indicating system is used, an additional sounding system is to be pro- vided for tanks which are not always accessible.

(7) Void compartments adjacent to the sea or

tanks containing liquids, and void compartments

through which piping carrying liquids passes are to be fitted with separate sounding pipes, ap- proved tank liquid level indicating apparatus or be fitted with means to determine if the void

tanks contain liquids. Voids as defined above which do not comply with this requirement are to be accounted for in the unit's stability analysis.

8. Ship-side valves

For the units for which the exemption of Docking survey is especially approved by the Society, special considerations are to be given to a prevention of corrosion and marine growth prevention to the valves, cocks and distance pieces fitted to the shell plating under the load water line.

9. Remote operation of sea-water inlet and discharge valves

(1) Each seawater inlet and discharge in spaces below the assigned load line should be provided with a valve operable from an accessible position outside the space on:

(A) all column-stabilized units or

(B) all other units where the space containing the valve is normally unattended and is not pro- vided with high bilge water level detection

(2) Where remote operation is provided by power-actuated valves for sea water inlets and discharges

for operation of propulsion and power generating machinery, power supply failure of the control system is not to result in closing of open valves or in opening of closed valves.

(3) Consideration will be given to accepting bilge alarms in lieu of remote operation for surface

type and self-elevating units specified in (1) (B).

10. Protection against flooding

(1) The control systems and indicators provided in Ch 4, 602. 1 (1) should be operable in both normal conditions and in the event of main power failure. Where stored energy is provided for this purpose, its capacity should be to the satisfaction of the Society.

(2) Nonmetallic expansion joints in piping systems, if located in a system which penetrates the unit’s side and both the penetration and the nonmetallic expansion joint are located below the deepest load waterline, should be inspected as part of the Docking survey in Ch 2, 304. and replaced as necessary, or at an interval recommended by the manufacturer.

11. Tests

Tests for the auxiliary machinery and piping are to be in accordance with the requirements in

109., notwithstanding the requirements in

Steel Ships.

Pt 5, Ch 6, Sec 13 of Rules for the Classification of

204. Jacking systems

The jacking systems are to be complied

Mobile Offshore Unit.

with Ch 10, 105. of Rules for the Classification of

205. Anchoring arrangements for surface and column-stabilized units

1. Anchoring arrangements, where fitted as the sole means for position keeping, should be provided with adequate factors of safety and be designed to maintain the unit on station in all design conditions. The arrangements should be such that a failure of any single component should not cause progressive failure of the remaining anchoring arrangements.

2. The anchors, cables, shackles and other associated connecting equipment should be designed, manu- factured and tested in accordance with an internationally recognized standard for offshore mooring equipment. Documentation of testing, where applicable, should be maintained on board the unit. Provisions should be made on board for the recording of changes to and inspection of the equipment.

3. Anchor cables may be of wire, rope, chain or any combination thereof.

4. Means should be provided to enable the anchor cable to be released from the unit after loss of main power.

5. Fairleads and sheaves should be designed to prevent excessive bending and wear of the anchor cable. The attachments to the hull or structure should be such as to adequately withstand the stresses imposed when an anchor cable is loaded to its breaking strength.

6. Suitable anchor stowage arrangements should be provided to prevent movement of the anchors in a seaway.

7. Each windlass should be provided with two independent power-operated brakes. Each brake should be capable of holding against a static load in the anchor cable of at least 50% of its breaking strength. Where the Society so allows, one of the brakes may be replaced by a manually operated brake.

8. The design of the windlass should provide for adequate dynamic braking capacity to control normal combinations of loads from the anchor, anchor cable and anchor handling vessel during the deploy- ment of the anchors at the maximum design payout speed of the windlass.

9. On loss of power to the windlasses, the power-operated braking system should be automatically ap- plied and be capable of holding against 50% of the total static braking capacity of the windlass.

10. Each windlass should be capable of being controlled from a position which provides a good view of the operation.

11. Means should be provided at the windlass control position to monitor cable tension and windlass power load and to indicate the amount of cable paid out.

12. A manned control station should be provided with means to indicate and automatically record ca- ble tensions and the wind speed and direction.

13. Reliable means should be provided to communicate between locations critical to the anchoring operation.

14. Special consideration should be given to arrangements where the anchoring systems provided are used in conjunction with thrusters to maintain the unit on station.

206. Dynamic positioning systems

Dynamic positioning systems used as a means of position keeping are to comply to the require- ments in Pt 9, Ch 4 of Rules for the Classification of Steel Ships.

207. Automatic and remote control for machinery

1. In cases where the automatic or remote control systems are adopted to the machinery installed in the units, the control devices and measuring instruments are to be such that the safe operation of the units can be made by the planned number of personnel.

2. The control system is to be designed to act, as far as possible, in fail-safe so as not to be in dan- ger of operators or not to damage the system concerned in the event of failure of the equipment or loss of the power source. The safety devices are, if necessary, to be provided independently from control systems.

3. The apparatus belonging to the systems or equipment essential for the safety of the units is to be provided with suitable means to ensure the safe operation of the units even when their automatic or remote control systems are out of service.

4. Machinery installations of the unit which has the periodically unattended machinery spaces are to

comply with the relevant requirements in Pt 9, Ch 3, 206. of Rules for the Classification of Steel Ships as well as the requirements in Ch 9.

208. Spare parts, tools and instruments

1. General

Spare parts, tools and instruments prescribed in this Article are generally to be provided on the units. For the units specially approved by the Society, those may be dispensed with.

2. Spare parts

(1) Spare parts for internal combustion engines, steam turbines and boilers used for the main source of electric power are to be in accordance with the requirements in Pt 5, Ch 1, Sec 4 of Rules for the Classification of Steel Ships.

(2) Spare parts for bilge pumps are to be in accordance with the requirements in Pt 5, Ch 1, Sec

4 of Rules for the Classification of Steel Ships.

(3) Spare parts for ballast pumps prescribed in 104. 7 are to be provided in accordance with the

requirements in Pt 5, Ch 1, Sec 4 of Rules for the Classification of Steel Ships.

(4) Spare parts for starting air compressors of internal combustion engines used for the main source

of electrical power are to be provided in accordance with the requirements in Pt 5, Ch 1, Sec

4 of Rules for the Classification of Steel Ships.

(5) The Society may require to provide spare parts for jacking systems.

3. Tools and instruments

Tools and instruments for boilers used for the main source of electrical are to be provided in accordance with the requirements in Pt 5, Ch 1, Classification of Steel Ships.

4. Spare Parts, tools and instruments for restricted service units

The restricted service units are to be in accordance with the requirements

power and for all boilers

Sec 4 of Rules for the

in Pt 5, Ch 1, Sec 4 of

Rules for the Classification of Steel Ships regarding as ships of restricted service.

209. Tests

1. General

(1) The tests for the machinery are to be in accordance with the requirements in this Article.

(2) The Society may require, where considered necessary, other tests than those prescribed in this Article.

(3) Where machinery has test certificates considered satisfactory by the Society, a part or all of

tests for the machinery may be dispensed with.

(4) As regards machinery manufactured by mass production system or specially controlled system, the Society may adopt test procedures suited to the production method, in place of tests stipu- lated in this rule, for the factory which considered suitable, upon the request of the manufacturer.

(5) The Society may adopt, where considered satisfactory, other test procedures than those stipulated in this Article.

2. Tests

(1) Boilers, pressure vessels belonging to PV -1 and PV -2, pipings and electrical equipment are to be tested in accordance with the relevant requirements in Pt 5 and Pt 6 of Rules for the Classification of Steel Ships. However, for pipings used solely for the operating purpose with the exclusion of those for inflammable or toxic media, tests may be dispensed with. For the ap- paratuses listed in the following (A) to (E), the testing at the manufacturer's works is to be car- ried out, where these apparatuses are used for the systems essential for the safety of the units. However, the high voltage tests considered suitable by the Society are to be carried out for electrical equipment with rated voltage above 3,000 V even where the equipment is not used for the systems or equipment essential for the safety of the units.

(A) Generators and motors

(B) Control gears for motors

(C) Switchboards

(D) Transformers for power and lighting

(E) Semi-conductor rectifiers for power

(2) Engines, shaftings and power transmission gears, pressure vessels belonging to PV-3 and auxil- iary machinery used for the systems or equipment essential for the safety of the units are to be tested in accordance with the relevant requirements in Pt 5 of Rules for the Classification of Steel Ships. However, the tests may be waived depending upon the usage of these installations where approved by the Society.

(3) The systems or equipment essential for the safety of the units are, after installation on board, to be subjected to performance tests.

(4) Remote control systems and automatic control systems for boilers and the systems or equipment

essential for the safety of the units are, after installation on board, to be subjected to perform- ance tests.

(5) Safety devices required by this rule are, after installation on board, to be tested.

(6) Running tests are, after installation on board, to be carried out for the generators stated in Ch 6 201. 6 and other electrical equipment not used for the systems essential for the safety of the units coming under the following (A) or (B).

(A) Where rated voltage exceeds d.c. 1,000 V or a.c. 3,000 V .

(B) Where parallel runnings (including changing over operation) are carried out with the main

source of electrical power.