Iranian Classification Society Rules

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Section 3 Surveys

301. General

1. Units classed with the Society are to be subjected to the following surveys to maintain the classification.

(1) Special Surveys

(2) Intermediate Surveys

(3) Annual Surveys

(4) Docking Surveys

(5) Surveys of Propeller Shaft and Stern Tube Shaft, Etc.

(6) Boiler Surveys

(7) Continuous Surveys

(8) Alteration Survey

(9) Occasional Surveys

2. Damage, failure and repair

(1) Examination

Damage, failure, deterioration or repair to the unit or its elements which affects or may affects classification is to be submitted by the Owners or their representatives for examination by the Surveyor.

(2) Repairs

Where repairs to the unit or its elements which may affect classification are planned in ad- vance, a complete repair procedure, including the extent of the proposed repair and the need for the Surveyor's attendance, is to be submitted to and agreed upon by the Surveyor reasonably in

advance. Failure to notify the Society in advance of the repairs may result in suspension of the unit's classification until such time as the repair is redone or evidence is submitted to satisfy the Surveyor that the repair was properly carried out.

Note : The above applies also to repairs during voyage or on site.

The above is not intended to include maintenance and overhaul to hull, machinery and equip- ment in accordance with manufacturer's recommended procedures and established marine practice and which does not require the approval of the Society. However, any repairs as a result of such maintenance and overhauls which affects or may affect classification is to be noted in the unit's log and submitted to the Surveyors for use in determining further survey requirements as required by (1) above. All repairs found necessary by the Surveyor are to be completed to the Surveyor's satisfaction.

3. Continuous Surveys

(1) At the

system carried

request of the Owner and upon the Society's approval of the proposed arrangements, a of Continuous Surveys may be undertaken whereby the Special Survey requirements are out in regular rotation to complete all of the requirements of the particular Special

Survey within a 5-year period. Each part(item) surveyed becomes due again for survey approx- imately five(5) years from the date of survey. The due parts(items) are generally to be com-

pleted each year. Continuous items that are three(3) months or more overdue at the time of Annual Survey attendance will be basis for the Annual Survey not to be credited and for non-endorsement of the Certificate of Classification. Consideration may be given by the Society

to an extension to complete survey items. If any defects are found during the survey, they are to be dealt with to the satisfaction of the Surveyor.

(2) Docking Survey or equivalent In-water Survey, as required by 304., may be performed at any

time within the five-year Special Survey period, provided that all requirements of 305. are met and thickness measurements are taken when the unit is surveyed.

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4. Lay-up and reactivation

(1) The Society is to be notified by the Owner that a unit has been laid-up. The surveys falling due during lay-up may then be held in abeyance until the unit reactivates. Lay-up procedures and arrangements for maintenance of conditions during lay-up may be submitted to the Society for review and verification by survey.

(2) The requirements for surveys on reactivation are to be specially considered in each case, with

due regard given to the status of surveys at the time of the commencement of the lay-up peri- od, the length of the period and the conditions under which the unit has been maintained dur- ing that period.

(3) Units returning to active service, regardless of whether the Society has been informed previously that the unit has been in lay-up, will require a Reactivation Survey.

5. Survey Reports File

All survey reports and records of all abnormalities found are to be compiled into the Survey Report File that is to be kept onboard the unit at all times for reference during any survey. The records to be kept include, but are not limited to, the following:

(1) Survey and Inspection Plan

(2) The updated status records of all class surveys

(3) The records of all abnormalities found that are to include all videos and photographic records

(4) The

records of all repairs performed on any abnormalities found and any further repetitive ab-

normalities found subsequent to the repairs

(5) Records of all corrosion prevention system maintenance, including records of all cathodic poten- tial readings taken, records of depletion of all sacrificial anodes, impressed current maintenance

records, such as voltage and current demands of the system, coating breaks and the monitoring records of the steel material wastage in way of the coating break areas

(6) All classification survey reports pertaining to the unit

(7) All records of any findings of abnormalities by the crew personnel onboard, including all lea- kages in bulkheads and piping

(8) Reports of thickness measurements of the unit

(9) Reports of all NDE performed

6. Surveys using risk-based techniques

A properly conducted Risk-Based Inspection Plan or Reliability Centered Maintenance Plan may be credited as satisfying requirements of surveys for maintenance of class for the corresponding unit. The application of this requirements does not cover any statutory survey requirements that may ap- ply to the unit being considered. Although the Society is authorized to perform statutory surveys on behalf of some authorities, the Society is not in a position to alter or waive them. The Owner is

to ensure that in developing the inspection plan applicable requirements external to the Society.

or maintenance plan, due consideration is given to

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302. Annual Survey

1. Due range

Annual Survey is to be carried out within 3 months before or after each anniversary date.

2. Hull and equipment

(1) All units(ship type)

For ship type units, at each Annual Survey, the weather decks, hull plating and their closing

appliances

cable and

together with watertight penetrations are to be generally examined as far as practi-

placed in satisfactory condition. The following documents, as applicable, are to be

available onboard during Annual Surveys:

(a) General Arrangement

(b) Capacity Plan

(d) List of Electrical Equipment

(e) Operations Manual

(f) Construction Portfolio

(g) Survey Reports File, as required by 301. 5

The survey is to include the following, as applicable:

(A) Protection of openings

(a) Hatchways, manholes and scuttles in freeboard and superstructure decks

(b) Machinery casings, fiddley covers, funnel annular spaces, skylights, companionways and deckhouses protecting openings in freeboard or enclosed superstructure decks

(c) Portlights together with deadcovers, cargo ports, bow or stern access, chutes and similar openings in unit's sides or ends below the freeboard deck or in way of enclosed super- structures

(d) Ventilators including closing devices where fitted, air pipes together with flame screens and weld connections to deck plating. All air pipe closure devices installed on the ex- posed decks are to be externally examined, randomly opened out and their condition verified. Scuppers, inlets and overboard discharges are to be externally examined as ac- cessible including their attachment to shell and valves.

(e) Watertight bulkheads, bulkhead penetrations, end bulkheads of enclosed superstructures and the operation of any doors in same

(f) Weathertight doors and closing appliances for all of the above including stiffening, dogs,

hinges and gaskets. Proper operation of weathertight doors and closing appliances to be confirmed.

(B) Freeing ports

Freeing ports, together with bars, shutters and hinges

Guard rails, lifelines, gangways and deck houses accommodating crew

(D) Loading and stability information

Confirmation of loading manual, stability data and damage control plans, as applicable. Loading instruments installed to supplement the trim and stability booklet are to be con- firmed in working order by use of the approved check conditions, as applicable. The user's instruction manual for the loading instrument is to be confirmed onboard.

(E) Load line

Confirmation that no alterations have been made to the hull or superstructures which would affect the calculation determining the position of the load lines. Record of conditions of as- signment of load lines is to be available onboard for reference. The load line marks are to be sighted, found plainly visible, and remarked and/or painted, as required.

(F) Mooring systems

(a) Spread mooring systems

The spread mooring system is to be generally examined so far as can be seen and placed in satisfactory condition as necessary. In addition, the following above water items are to be examined, placed in satisfactory condition and reported upon, where ap- plicable:

(i) The anchor chain stopper structural arrangements are to be visually examined, in- cluding the structural foundations of all of the stoppers or holders. Tensioning equip- ment is to be generally examined.

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(ii) The anchor chain's catenary angles are to be measured to verify that the anchor chain tensions are within the design allowable tolerances. Where anchor cables are used, their tensions are to be verified to be within the allowable tensions.

(iii)The anchor chains or anchor cables above the water are to be visually examined for wear and tear.

(b) Single point mooring(SPM) systems

The single point mooring system is to be generally examined so far as can be seen above water and placed in satisfactory condition as necessary. In addition, the following above water items are to be examined, placed in satisfactory condition and reported upon, where applicable:

(i) The anchor chain stopper structural arrangements are to be visually examined, in- cluding the structural foundations of all of the stoppers.

(ii) The anchor chain's catenary angles are to be measured to verify that the anchor chain tensions are within the allowable design tolerances. Where anchor cables are

used, their tensions are to be verified to be within the allowable tensions.

(iii)The anchor chains or anchor cables above the water are to be visually examined for wear and tear.

(iv) The condition of the bearings is to be verified for continued effectiveness of the

lubrication system.

(v) The entire assembly of the single point mooring structure above water is to be gen- erally examined for damage, coating breaks and excessive signs of corrosion. This

survey is to include all turret wall structures, accessible turret well structures, moor- ing arms, all structures supporting the disconnectable operations of the mooring sys-

tem, etc., whichever are applicable.

(G) Structural fire protection

Verification that no significant changes have been made to the arrangement of structural fire protection, verification of the operation of manual and/or automatic fire doors, if fitted, and verification that the means for escape from the accommodations, machinery spaces and other

spaces are satisfactory.

(H) Suspect areas

Suspect areas of the hull are to be overall examined, including an Overall and Close-up

Survey

stantial Where

of those suspect areas which were identified at the previous surveys. Areas of sub-

corrosion identified at previous surveys are to have thickness measurements taken. extensive areas of corrosion are found or when considered necessary by the

Surveyor, thickness measurements are to be carried out and renewals and/or repairs made

when wastage exceeds the allowable margin. Where substantial corrosion is found, additional thickness measurements in accordance with Pt 1, Ch 2, Table 1.2.5 of Rules for the Classification of Steel Ships are to be taken to confirm the extent of substantial corrosion. These extended thickness measurements are to be carried out before the survey is credited as completed. Where reduced scantlings on the basis of effective corrosion pre- vention system have been adopted, the results of any measurements are to be evaluated based on the scantlings before reduction.

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(I) Ballast tanks and combined cargo/ballast tanks

5 years < age ≤ 15 years

15 years < age

1. Ballast tanks and combined cargo/ballast tanks other than double bottom tanks, where the following conditions have been identified at previous surveys.

- A hard protective coating was found in POOR con- dition, or

- A soft coating or semi-hard coating has been ap- plied, or

- A hard protective coating has not been applied from the time of construction

2. Double bottom ballast tanks, where substantial corro- sion was found within the tank, and the following conditions have been identified at previous surveys

- A hard protective coating was found in POOR con- dition, or

- A soft coating or semi-hard coating has been ap- plied, or

- A hard protective coating has not been applied from the time of construction

1. Ballast tanks and combined cargo/ballast tanks other than double bottom tanks, where the following con- ditions have been identified at previous surveys.

- A hard protective coating was found in POOR con- dition, or

- A soft coating or semi-hard coating has been ap- plied, or

- A hard protective coating has not been applied from the time of construction

2. Double bottom ballast tanks, where substantial corro- sion was found within the tank, and the following conditions have been identified at previous surveys

- A hard protective coating was found in POOR con- dition, or

- A soft coating or semi-hard coating has been ap- plied, or

- A hard protective coating has not been applied from the time of construction

3. Ballast tanks and combined cargo/ballast tanks other than double bottom tanks in way of spaces designated for the carriage of cargo, where FAIR coating con- ditions were identified at previous surveys, a mini- mum of three (3) so identified tanks, i.e., one (1) forward, one (1) midship and one (1) aft.

4. Peak tanks, where FAIR coating conditions were iden- tified at previous surveys.

(NOTES)

1) Where extensive areas of corrosion are found or when considered necessary by the Surveyor, thickness measurements are to be carried out and renewals and/or repairs made when wastage exceeds the allowable margin. Where substantial corrosion is found, additional thickness measurements in accordance with Pt 1, Ch 2, Table 1.2.5 of Rules for the Classification of Steel Ships are to be taken to confirm the extent of substantial corrosion. These extended thickness measurements are to be carried out before the survey is credited as completed. Where reduced scantlings on the basis of effective corrosion prevention system have been adopted, the results of any measurements are to be evaluated based on the scantlings before reduction.

(J) Helicopter deck

Where areas of the unit are designated for helicopter supporting structure, deck surface, deck drainage, tie

operations, the helicopter deck, deck downs, markings, lighting, wind in-

dicator, securing arrangements, where fitted safety netting or equivalent, access arrangements

including emergency escape, and access for fire fighting and rescue personnel, are to be examined.

(K) Units in lightering service

The external examination of hull structures, where fenders for lightering operation were lo- cated, is to be carried out. Where extensive areas of wastage are found, or when considered necessary by the Surveyor, thickness measurements and internal examination, including Close- up Survey, may be required.

(2) Column-stabilized units

For column-stabilized units, the exposed parts of the hull, the deck, deck houses, structures at- tached to the deck, derrick substructure, including supporting structure, accessible internal spaces

and the

isfactory

applicable parts listed as follows are to be generally examined and placed in sat-

condition, as found necessary:

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(A) Hatchways, manholes, and other openings in freeboard deck(bulkhead deck) and enclosed su- perstructure decks

(B) Machinery casings and covers, companionways and deck houses protecting openings in free-

board or enclosed superstructure decks

(C) Portlights together with deadcovers, cargo ports, bow or stern access, chutes and similar openings in hull sides or ends below the freeboard deck or in way of enclosed super- structures

(D) Ventilators, tank vent pipes together with flame screens and overboard discharges from en- closed spaces on or below the freeboard deck

(E) Watertight bulkheads and end bulkheads of enclosed superstructures

(F) Closing appliances for all of the above, including hatch covers, doors, check valves

(G) Protection of the crew, guard rails, lifelines, gangways and deckhouses accommodating crew

(H) Columns, diagonals and other parts of the upper hull supporting structure as accessible above the waterline

(I) The Surveyors are to confirm that no alterations have been made to the hull, structural ar-

rangements, subdivision, superstructure, fittings and closing appliances upon which the load line assignment is based.

3. Fire protection and fire fighting systems

Following systems are to be verified to confirm no significant changes have been made to any of the systems and that they remain in satisfactory condition.

(1) Fire protection systems, including the following items are to be generally examined and function tested as necessary:

(A) Examination of structural fire protection of accommodation spaces, service spaces and con- trol stations, as accessible

(B) Examination and function testing of fire doors

(D) Examination and testing of ventilation system closures and stoppage of power ventilation

(E) Examination and testing of shutters or water curtains

(2) Fixed fire extinguishing systems, including the following items are to be generally examined and function tested as necessary:

(A) Examination of all items shown on the fire control plan, and confirmation that no alteration

has been made to the Society endorsed plan

(B) Examination and testing of all fire pumps. Other pumps used for active fire protection are also to be examined. This is to include confirmatory testing of the fire pump capacity, and

where installed, testing of relief valves of the fixed fire main system.

(D) Examination necessary

of all hydrants, hoses, nozzles, and shore connections, and testing of these as

(E) Examination and testing of the gas smothering system, including confirmatory examination of the storage of the gas medium, gas alarms, and examination and testing of manual controls

(F) Examination of the high or low expansion foam systems

(G) Examination and function testing of fixed water spraying systems

(H) Protection of helicopter decks with or without refueling capacity

(I) Examination of paint and flammable liquid lockers

(3) All portable and semi-portable extinguishers are to be examined.

(4) The firefighter’s outfit are to be tested and examined, as necessary.

(5) Fire detection and alarm systems are to be examined and tested as necessary.

(6) Gas detection and alarm systems are to be examined and tested as necessary.

(7) Means of escape, including the following items, are to be examined and tested as necessary:

(A) All escape routes from accommodation spaces, service spaces and control stations, from Category ‘A’ machinery spaces, from other machinery spaces, deckhouses

(B) Lighting and gratings in way of all escape routes

(D) Contact makers for general alarm system, communication system installed in all emergency control stations

(8) Emergency shutdown systems

(A) Emergency shutdown arrangements simultaneously, of the electrical

provided to disconnect or shutdown, either selectively or equipment as outlined in the floating production in-

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Ch 2 Classification and Surveys Ch 2

stallation’s operating manual, are to be examined and tested.

(B) Services such as the emergency lighting, general alarm system, public address system, dis- tress and safety radio system, that are required to be operable after an emergency shutdown of the installation, are to be verified for their proper operation.

(C) All equipment in exterior locations which is capable of operation after an emergency shut- down is to be verified as being suitable for installation in Zone 2 locations.

4. Machinery and electrical equipment

(1) Annual Survey of machinery and electrical systems is mandatory for all types of units.

(2) Survey items not specified in this Paragraph are to be in accordance with the followings.

(A) Surveys for ship type units are to comply with applicable requirements of Pt 1, Ch 2, 203.

of Rules for the Classification of Steel Ships.

(B) Surveys for column-stabilized installations are to comply with applicable requirements of Ch 2, 302. of Rules for the Classification of Mobile Offshore Drilling Units.

(3) Non self propelled unit

Machinery items installed consistent with the services of the installation are subject to a general examination and are to be placed in satisfactory condition.

(4) Self propelled unit

(A) Surveys of self propelled installations is to comply with applicable requirements of Pt 1, Ch 2, 203. of Rules for the Classification of Steel Ships.

(B) Thruster surveys, where installed, are to comply with the requirements of Pt 1, Annex 1-9

of Guidance relating to the Rules for the Classification of Steel Ships.

(5) Surveys of machinery that has been accepted for surveys based on preventative maintenance

techniques are to comply with the requirements of Pt 1, Annex 1-8 of Guidance relating to the Rules for the Classification of Steel Ships.

(6) Enclosed hazardous areas, including ventilation, electric lighting, electric fixtures and in-

strumentation is to be examined.

(7) The integrity of explosion-proof equipment is to be verified.

(8) Corrosion protection systems are to be examined.

(9) Remote shutdown arrangements for fuel and ventilation equipment are to be examined and tested.

(10) Emergency control stations are to be examined and tested.

(11) Safety relief valves are to be externally examined and tested.

(12)

All machinery, pumps and pumping arrangements, including valves, cocks and pipes are to be

externally examined during operation.

(13) Preventative maintenance records are to be examined.

(14) Structure, piping, electrical systems and machinery foundations are to be generally examined for damage or deterioration.

(15) Cargo Tanks

Pressure/vacuum relief valves, flame arrestors and flame screens, tank vent protective devices are to be examined externally for proper assembly and installation, damage, deterioration or traces of carryover at the outlet. Where deemed suspect, the tank protective device is to be opened for examination.

(16) Cargo Pump Room

(A) Examination of pump room bulkheads for signs of leakage or fractures and, in particular, the sealing arrangement of all penetrations of bulkheads.

(B) Confirmation that there are no potential sources of ignition in or near the cargo pump room and cargo area and that pump room access ladders are in good condition.

5. Dynamic positioning systems (if relevant notations are assigned)

Surveys of dynamic positioning systems are to comply with the requirements of Pt 9, Ch 4 of

Rules for the Classification of Steel Ships.

6. Production systems (if relevant notations are assigned)

(1) Maintenance records are to be kept and made available for review by the Surveyor. The main- tenance records will be reviewed to establish the scope and content of the required Annual and Special Periodical Surveys. During the service life of the facilities, maintenance records are to be updated on a continuing basis. The operator is to inform the Society of any changes to the maintenance procedures and frequencies, as may be caused, for example, by changes or addi-

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tions to the original equipment.

(2) Enclosed hazardous areas, including ventilation, electric lighting, electric fixtures and in- strumentation is to be examined.

(3) The integrity of explosion-proof equipment is to be verified.

(4) Corrosion protection system is to be examined.

(5) Remote shutdown arrangements for fuel and ventilation equipment is to be examined and tested.

(6) Emergency control stations are to be examined and tested.

(7) Safety relief valves are to be externally examined and tested.

(8) All machinery, pumps and pumping arrangements, including valves, cocks and pipes are to be externally examined during operation.

(9) Structure, piping, electrical systems and machinery foundations are to be generally examined for damage or deterioration.

7. Import and export systems (if relevant notations are assigned)

The import and export systems are to be examined as far as can be seen and placed in satisfactory condition. In addition, the following items are to be examined:

(1) A general examination is to be performed on all electrical and fluid swivels, flexible risers,

floating hoses, cargo piping and valves associated with the import and export systems, expansion joints, seals, etc.

(2) The fluid swivels are to be examined for signs of leaks through their “tell-tale” apertures.

(3) Records of maintenance are to be reviewed.

(4) Navigational aids for all floating hoses are to be examined and functionally tested.

(5) Riser tensioning arrangements are to be examined for proper functioning order.

(6) All electrical equipment, fitted in hazardous location is to be examined for integrity and suit- ability for the continued service.

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303. Intermediate Surveys

1. Due range

Intermediate Surveys are to be carried out either at the second or third Annual Survey or between these surveys.

2. Hull and equipment

(1) Ship type units

At the Intermediate Survey, in addition to all the requirements for Annual Survey, the follow- ing items are to be surveyed.

(A) Survey planning meeting

A survey planning meeting is to be held prior to the commencement of the survey.

(B) Ballast tanks

5 years < age ≤ 10 years

10 years < age

1. Overall Survey of a minimum three(3) representative ballast tanks selected by the Surveyor1)

1. Overall Survey of all ballast tanks

(NOTES)

1) Where a hard protective coating is found in POOR condition, where soft coating or semi-hard coating has been applied or where a hard protective coating has not been applied from time of construction, the examina- tion is to be extended to other ballast tanks of the same type.

2) If such Overall Survey reveals no visible structural defects, the examination may be limited to verification that the corrosion prevention system remains effective.

3) Where provided, the condition of corrosion prevention system of ballast tanks and combined cargo/ballast tanks other than double bottom ballast tanks is to be examined. Ballast tanks and combined cargo/ballast tanks other than double bottom ballast tanks, where a hard protective coating is found in POOR condition and Owners or their representatives elect not to restore the coating, where a soft coating or semi-hard coating has been applied or where a hard protective coating has not been applied from the time of construction, the tanks in question are to be internally examined at each subsequent Annual Survey. Thickness measurements are to be carried out as considered necessary by the Surveyor.

4) Double bottom ballast tanks, where a hard protective coating is found in POOR condition and owners or their representatives elect not to restore the coating, where a soft coating or semi-hard coating has been applied or where a hard protective coating has not been applied from the time of construction, the tanks in question may be internally examined at each subsequent Annual Survey where substantial corrosion is documented. Thickness measurements are to be carried out as considered necessary by the Surveyor.

At each Intermediate Survey after Special Survey No. 2, at least three (3) cargo tanks of integral type(one(1) center, one(1) port wing and one(1) starboard wing tank) are to be ex- amined internally.

(D) Thickness measurements

Where extensive areas of corrosion are found or when considered necessary by the Surveyor, thickness measurements are to be carried out and renewals and/or repairs made when wastage exceeds the allowable margin. Where reduced scantlings on the basis of ef- fective corrosion prevention system have been adopted, the results of any measurements are

to be evaluated based on the scantlings before reduction.

(E) Tank pressure testing

Pressure testing of cargo and ballast tanks is not required unless deemed necessary by the Surveyor.

(F) Units in lightering service

The external examination and internal Close-up Survey of hull structures, including thickness measurements, where fenders for lightering operation were located, are to be carried out.

(2) Column-stabilized units

Intermediate Surveys are not required for column-stabilized units.

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3. Fire protection and fire fighting systems

At each Intermediate Survey, all the requirements of Annual Survey are to be

4. Machinery and electrical equipment

At each Intermediate Survey, all the requirements of Annual Survey are to be

5. Dynamic positioning systems (if relevant notations are assigned)

At each Intermediate Survey, all the requirements of Annual Survey are to be

6. Production systems (if relevant notations are assigned)

At each Intermediate Survey, all the requirements of Annual Survey are to be

7. Import and export systems (if relevant notations are assigned)

At each Intermediate Survey, all the requirements of Annual Survey are to be

complied with. complied with. complied with. complied with.

complied with.

304. Special Surveys

1. Due range

(1) A Special Survey is to be completed within five(5) years after the date of build or after the crediting date of the previous Special Survey. The fifth Annual Survey must be credited as a requirement of the Special Survey. The interval between Special Survey may be reduced by the Society if it considered necessary.

(2) Special Survey may be commenced at the fourth Annual Survey and be continued with com- pletion by the fifth anniversary date. Where the Special Survey is commenced prematurely, the entire survey is normally to be completed within 15 months if such work is to be credited to the Special Survey.

(3) Special consideration may be given to Special Survey requirements in the case of units of un- usual design, in lay-up or in unusual circumstances. Consideration may be given for extensions of rule-required Special Surveys under exceptional circumstances.

2. Hull and equipment

Special Survey is to include compliance with the Annual Survey and Docking Survey requirements and, in addition, the following requirements as listed below are to be performed, as applicable, the parts examined, placed in satisfactory condition and reported upon.

(1) Ship type units

In addition to the requirements of the Annual Survey, the Special Survey is to include suffi- cient examination, tests and checks carried out by the Surveyors to satisfy themselves that the

hull, equipment and related piping are in or are placed in satisfactory condition and are fit for

the intended purpose for the new period of class of five(5) years to be assigned,

proper maintenance and operation and to periodical surveys being carried out at the Special Survey is to include the following:

(A) Survey planning meeting

subject to due dates.

A survey planning meeting is to be held prior to the commencement of the survey.

(B) Docking Survey

Docking surveys are to be carried out in accordance with 305.

When the steering gear is maintained operational the rudder is to be examined and, when

considered necessary by the Surveyor, lifted and the gudgeons rebushed. The condition of rudder carrier and steadiment/rudder stock bearings and the effectiveness of stuffing boxes are to be ascertained when the rudder is lifted.

(D) Mooring systems

Since it is impractical to cover all types of mooring systems, the following are provided as guidance to show the basic intent of the survey requirements. Operators and designers may submit alternative survey requirements based either on service experience or manufacturer' recommendations. If considered acceptable by the Society, these alternative survey proce- dures will form the basis for the Special Survey of the mooring system. The Special Survey is to include all items listed under the Annual Survey and, in addition, the following are to be performed, where applicable:

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(a) A Docking Survey out. This survey is

or equivalent In-water Survey of the SPM system is to be carried to include examination of the entire structure of the SPM, the pro-

(b)

tective coating, cathodic protection system, the chain stoppers and their locking devices.

Any suspect areas where substantial corrosion is evident are to be thickness gauged. Gaugings to the extent considered necessary by the Surveyor are to be taken on the structures of the SPM when it has undergone service for 15 years or more.

An examination is to be made on all anchor chains for substantial corrosion and wastage. In particular, the areas to be specially examined are the areas having the most relative movement between the chain links. These areas are normally located in way of the seabed touchdown sections of the catenary part of the chains. The chains are to be inspected for looses studs and link elongations. Sufficient representative locations are to

(c)

be gauged for wear and wastage. Areas susceptible to corrosion, wind-and- water areas, are to be specially gauged, if considered necessary ing

Surveyor.

A close examination is to be carried out on all mooring components

structural members that carry the mooring loads. These structures include

such as the by the attend-

and accessible the chain stop-

(d)

(e)

(f)

pers or cable holders, the structures in way of the chain stoppers or cable holders,

structural bearing housing and turret/structural well annulus areas. These structures are to be thoroughly cleaned and examined and any suspect areas are to be nondestructively tested.

A general inspection is also to be carried out on the degree of scour or exposure in way of the anchor or anchor piles to ascertain that these components are not overexposed.

An examination is to be carried out on the main bearing of the SPM system. This ex-

amination is to include visual inspection of bearing, if accessible, for water ingress into the structural housing, corrosion, pitting and substantial wear. If the bearing is in- accessible, at least the weardown is to be ascertained and the condition of the bearing seals verified. If disassembled, the bearing rollers and the racer housings are to be examined.

For inaccessible structures, special alternative inspection procedures for inspection of these areas are to be submitted for approval.

(g) The chain tensions are to be checked and where found not in compliance with the spec- ifications are to be readjusted accordingly. Excessive loss of chain or tendon tensions

are to be investigated.

(h)

Representative areas of the chains are to be examined and checked for substantial wastage. In particular, areas in way of the chain stoppers and the seabed touchdown areas are to be specially examined and measured for substantial wear.

(i) For disconnectable type mooring systems, the disconnect and connect system for the

mooring system is to be tested as considered necessary by the Surveyor. Alternatively, records of disconnect/connect operations between the credit date of the last Special Survey and the current due date of same may be reviewed, and if found satisfactory, it may be considered to have been in compliance with this requirement.

(E) Shell openings and their closures

All openings in the shell including overboard discharges are to be examined.

(F) Decks, bulkheads and shell plating

All decks, watertight bulkheads, and internal and external surfaces of shell plating are to be examined. Plating in way of side shell or superstructure portlights is to be especially

examined.

(G) Overall Survey requirement

(a) Spaces

(i) An Overall Survey of all spaces including cargo holds and their tween decks, where fitted; double bottom, deep, ballast, peak and cargo tanks; pumprooms, pipe tunnels,

duct keels, machinery spaces, dry spaces, cofferdams and voids, including the plating and framing, bilges and drain wells, sounding, venting, pumping and drainage

arrangements.

(ii) Internal examination of fuel oil, lube oil and fresh water tanks is to be carried out in accordance with (d) below.

(iii)Where sounding pipes are fitted, the Surveyor is to confirm that a striking pad is

securely fixed below the sounding pipe.

18 Guidance for Floating Production Units 2015

Ch 2 Classification and Surveys Ch 2

(iv)Electrical bonding arrangements, including bonding straps where fitted, for the pip- ing systems located within cargo tanks, pipe tunnels, cofferdams and void spaces bounding cargo tanks are also to be examined.

(v) This examination is to be supplemented by thickness measurement and testing as re-

quired in this Guidance to

ensure that the structural integrity remains effective. The

aim of the examination is to discover substantial corrosion, significant deformation,

fractures, damages or other

(b) Engine room spaces

structural deterioration, that may be present.

Engine room structure is to be examined. Particular attention is to be given to tank tops, shell plating in way of tank tops, brackets connecting side shell frames and tank tops, and engine room bulkheads in way of tank top and bilge wells. Particular atten- tion is to be given to the sea suction, seawater cooling pipes and overboard discharge

valves and their connections to the side shell plating. Where wastage is evident or sus-

pect, thickness measurements are to be carried out, and renewals and/or repairs made

where wastage exceeds allowable limits.

(i) Where provided, the condition of corrosion prevention system of ballast tanks and combined cargo/ballast tanks is to be examined.

(ii) Ballast tanks and combined cargo/ballast tanks other than double bottom ballast tanks, where a hard protective coating is found in POOR condition and Owners or

their representatives elect not to restore the coating, where soft coating or semi-hard coating has been applied or where a hard protective coating has not been applied

from the time of construction, the tanks in question are to be internally examined at

each subsequent Annual Survey. Thickness measurements are deemed necessary by the Surveyor.

(iii) When such breakdown of hard protective coating is found in

tanks and owners or their representatives elect not to restore

to be carried out as

double bottom ballast the coating, where a

soft coating or semi-hard coating has been applied, or where a hard protective coat-

ing has not been applied from the time of construction, the tanks in question are to be internally examined at each subsequent Annual Survey where substantial corrosion is documented. Thickness measurements are to be carried out as considered neces- sary by the Surveyor.

(d) Fuel oil, lubrication oil, fresh water and permanent ballast tanks

(i) Internal examination requirements will be specially considered for tanks used ex-

(ii)

clusively for permanent ballast which are fitted with an effective means of control.

Where tanks of integral structural type, except for peak tanks, are used

for heavy fuel oil or exclusively for light oils or fresh water, the internal

corrosion

primarily examina-

tion may be specially considered, provided a general external examination and the

following internal examinations are carried out if considered necessary by the Surveyor.

(iii) Independent oil tanks in machinery spaces are to be externally examined and, if

considered necessary by the Surveyor, tested under a head of liquid to the highest point that liquid will rise under service conditions.

(iv) Minimum requirements for internal examination of fuel oil, lubrication oil and fresh

water tanks at Special Surveys are as follows.

Guidance for Floating Production Units 2015 19

Ch 2 Classification and Surveys Ch 2

No. of Special Survey Tanks	Special No. 1	Survey	Special No. 2	Survey	Special No. 3	Survey	Special Survey No. 4 and Subsequent
Fuel oil tank	Engine room	-	-		1		1
	Cargo length area	-	12)		23)		Half, minimum 24)
Lubrication oil tank	-		-		-		1
Fresh water tank	-		1		○		○
(NOTES) 1) If a selection of tanks is accepted for examination, then different tanks are to be examined at each Special Survey on a rotational basis. 2) For units without a defined cargo area a minimum of one(1) fuel oil tank. 3) For units without a defined cargo area a minimum of two(2) fuel oil tanks. One(1) deep tank for fuel oil is to be included, if fitted. 4) For units without a defined cargo area, half of all fuel oil tanks, a minimum of two(2). One(1) deep tank for fuel oil is to be included, if fitted.

(H) Protection of other

(a) Tank protective

openings devices

(i) All tank protective devices, where fitted, are to be examined externally for proper assembly and installation, damage, deterioration or traces of carryover at the outlets.

(ii) All pressure-vacuum valves and pressure relief valves are to be opened out, pressure

and vacuum valve discs checked for good contact with their respective seats and/or proved by testing.

(b) Air pipes

All air pipes are to be opened out and closing arrangements and flame screens, if fit- ted, are to be examined both externally and internally. For designs where the inner parts cannot be properly examined from outside, this is to include removal of the head from the air pipe. Particular attention is to be paid to the condition of the zinc coating in heads constructed from galvanized steel.

Watertight bulkheads, bulkhead penetrations, end bulkheads of enclosed superstructures are to be examined. In addition, watertight doors are to be operationally tested and ef- fectiveness to maintain tightness is to be confirmed.

(I) Close-up Survey requirements

The requirements for Close-up Survey and thickness measurement in accordance with Pt 1, Ch 3, Sec 3 or Sec 5 of Rules for the Classification of Steel Ships will be applied to ship type and barge type units in the following cases:

(a) The ballast tanks are uncoated

(b) Tank coatings are in FAIR or Poor condition

(d) Substantial corrosion is present

20 Guidance for Floating Production Units 2015

Ch 2 Classification and Surveys Ch 2

(J) Thickness measurements requirements

Minimum requirements for thickness measurements are as follows. These requirements do not apply to independent cargo tanks.

Special Survey No. 1

Special Survey No. 2

Special Survey No. 3

Special Survey No. 4 and Subsequent

1. Suspect areas throughout the unit

2. All main deck plates within the amidships 0.5L or cargo tank section, whichever is longer

3. One(1) transverse section within the amidships 0.5L

4. Shell plates in wind-and-water strakes outside the amidships 0.5L

5. All complete transverse web frame rings in a ballast wing tank or ballast double hull tank, if any

6. One(1) deck transverse in each of the remaining ballast tanks, if any

7. Both transverse bulkheads including girder system in a ballast wing tank or ballast double hull tank, if any, or a cargo wing tank used primarily for water ballast

8. Lower part of transverse bulkhead including girder system in each remaining ballast tank, one(1) cargo wing tank and two(2) cargo center tanks

9. Internals in forepeak tank and afterpeak tank

1. Suspect areas throughout the unit

2. All main deck plates within the amidships 0.5L or cargo tank, whichever is longer

3. Two (2) transverse sections within the amidships 0.5L

4. Shell plates in wind-and-water strakes outside the amidships 0.5L

5. All complete transverse web frame rings in all ballast tanks and in a cargo wing tank

6. A minimum of 30% of all complete transverse web frame rings in each remaining cargo wing tank (In calculating the 30% minimum, the number of web frame rings is to be rounded up to the next whole integer)

7. A minimum of 30% of deck and bottom transverse in each cargo center tank (In calculating the 30% minimum, the number of transverses is to be rounded up to the next whole integer)

8. All transverse bulkheads including girder and stiffener systems in all cargo tanks and ballast tanks

9. Additional complete transverse web frame rings as considered necessary by the Surveyor

10. Internals in forepeak tank and afterpeak tank including plating and stiffeners of forepeak tank and afterpeak tank bulkheads

1. Suspect areas throughout the unit

2. All exposed main deck plates, full length. Also, exposed first-tier superstructure deck plates(poop bridge and forecastle decks)

3. All keel plates full length.

Also, additional bottom plates in way of cofferdams, machinery space and aft ends of tanks

4. A minimum of three (3) transverse sections within the amidships 0.5L

5. All complete transverse web frame rings in all ballast tanks and in a cargo wing tank

7. A minimum of 30% of deck and bottom transverse in each cargo center tank (In calculating the 30% minimum, the number of transverses is to be rounded up to the next whole integer)

8. All transverse bulkheads including girder and stiffener systems in all cargo tanks and ballast tanks

9. Additional complete transverse web frame rings as considered necessary by the Surveyor

10. Any additional tanks and structure as considered necessary by the Surveyor

11. Internals in forepeak tank and afterpeak tank including plating and stiffeners of forepeak tank and afterpeak tank bulkheads

12. All plates in wind-and-water strakes, full length

13. Plating of sea chests. Shell plating in way of overboard discharges as considered necessary by the Surveyor

(NOTES)

1) Thickness measurement locations are to be selected to provide the best representative sampling of areas likely to be most exposed to corrosion, considering cargo and ballast history and arrangement and condition of protective coatings.

Guidance for Floating Production Units 2015 21

Ch 2 Classification and Surveys Ch 2

(K) Tank testing

(a) Boundaries of double bottom, deep, ballast, peak and other tanks, including holds adapt- ed for the carriage of water ballast if fitted, are to be tested with a head of liquid to the top of air pipes or to near the top of hatches for ballast/cargo holds, except that cargo tanks on ship type units of both single and double hull construction may be test- ed to the highest point that liquid will rise under service condition. Boundaries of fuel oil, lube oil and fresh water tanks may be tested with a head of liquid to the highest point that liquid will rise under service condition. Tank testing of fuel oil, lube oil and fresh water tanks may be specially considered based on a satisfactory external examina- tion of the tank boundaries, and a confirmation from the Master stating that the pressure testing has been carried out according to the requirements with satisfactory results, pro- vided that representative tanks for fuel oil, lube oil and fresh water are tested.

(b) The testing of double bottoms and other spaces not designed for the carriage

of liquid

may be omitted, provided a satisfactory internal examination together with an examina- tion of the tanktop is carried out.

(d) The Surveyor may require further tank testing, as deemed necessary.

(L) Units in lightering service

The external examination and internal Close-up Survey of hull structures, including measurements, where fenders for lightering operation were located are to be carried

(2) Column-stabilized units

thickness out.

For column-stabilized units, the following are to be performed, as applicable, the parts exam- ined, placed in satisfactory condition and reported upon:

(A) The hull or platform structure, including tanks, watertight bulkheads and decks, cofferdams,

void spaces, sponsons, chain locker, deck, keels, helicopter pad, machinery spaces, peak spaces, steering gear spaces and all other internal spaces are to be examined externally and internally for damage, fractures or excessive wastage.

(B) All tanks, compartments and free-flooding spaces throughout the unit are to be examined ex- ternally and internally. Internal examinations of lower hull are to be specially considered. Watertight integrity of tanks, bulkheads, hull, bulkhead deck and other compartments are to be verified by visual inspection. Suspect areas may be required to be tested for tightness, nondestructively tested or thickness gauged. Tanks and other normally closed compartments are to be ventilated, gas-freed and cleaned, as necessary, to expose damage and allow for a meaningful examination for substantial wastage. Internal examination and testing of void

spaces, compartments filled with foam or corrosion inhibitors and tanks used only for

oil, light fuel oil, diesel oil or other non-corrosive products may be waived, provided

lube

that,

upon general examination, the Surveyor considers their condition to be satisfactory. External thickness gauging may be required to confirm corrosion control.

way of selective anchor line fairlead support structures are to be cleaned and nondestructive examinations performed. Internal support structures in way of these foundations are to be closely examined.

(D) Applicable structures, such as pipe racks, process support structures, deck houses, super- structures, helicopter landing areas and their respective attachments to the deck or hull.

(E) Foundations and supporting headers, brackets and stiffeners for process related apparatus, where attached to hull, deck, superstructure or deck house.

(F) Survey of parts of the unit that are underwater and inaccessible to the Surveyor may be ac- cepted on the basis of an examination by a qualified diver, conducted in the presence of

the Surveyor. Video or photo records, nondestructive testing and thickness gauging may be

required in addition to the diver's report.

(G) At each Special Survey, thickness gaugings are to be performed where wastage is evident or suspected. Special attention should be paid to the splash zones on hulls, columns and ballast

tanks, free-flooded spaces and the bottom hulls.

(H) Where inspection of underwater parts is required, the in-water visibility and the cleanliness are to be clear enough to permit a meaningful examination which allows the Surveyor and

diver to determine the condition of underwater parts.

(I) Connections of columns and diagonals to upper hull or platform and lower hull or pontoons.

Joints of sets and

supporting structure, including diagonals, braces and horizontals, together with gus- brackets. Internal continuation or back-up structure for the above. Nondestructive

22 Guidance for Floating Production Units 2015

Ch 2 Classification and Surveys Ch 2

examination may be required at suspect areas.

3. Fire protection and fire fighting systems

Special Survey is to include compliance with the Annual Survey requirements and, in addition, the following requirements as listed below are to be performed, as applicable, the parts examined, placed in satisfactory condition and reported upon. Following systems are to be verified to confirm no significant changes have been made to any of the systems and that they remain in satisfactory condition.

(1) Fire protection systems, including the following items are to be tested:

(A) Function testing of all fire doors

(B) Function testing of all ventilation fire-dampers

(D) Function testing of all shutters or water curtains

(2) Fixed fire extinguishing systems, including the following items are to be tested:

(A) Function testing of all fire pumps. This is to include confirmatory testing of the fire pump capacity and testing of relief valves of the fixed fire main system.

(B) Hydrostatic testing of the fire main system

(3) Fire detection and alarm systems are to be tested.

(4) Gas detection and alarm systems are to be tested.

(5) Means of escape, including the following items are to be tested:

(A) Lighting and grating in way of all escape routes

(B) Contact makers for general alarm system, communication system installed in all emergency control stations

(6) Emergency shutdown systems

(A) Emergency shutdown arrangements provided to disconnect or shutdown, either selectively or simultaneously, of the electrical equipment as outlined in the unit’s operating manual, are to be tested.

(B) Services such as the emergency lighting, general alarm system, public address system, dis-

tress and safety radio system, that are required to be operable after an emergency shutdown of the installation, are to be verified for their proper operation.

4. Machinery and electrical equipment

(1) Correlation with Special Survey of hull

(A) Main and auxiliary engines of all types of installations are to undergo Special Periodical Survey at intervals similar to those for Special Survey of hull in order that both may be re- corded at approximately the same time.

(B) In cases where damage has involved extensive repairs and examination, the survey thereon

may be considered as equivalent to a Special Survey.

(2) Machinery Parts to be Examined

(A) All openings to the sea, including sanitary and other overboard discharges together with the

cocks and valves connected therewith, are to be examined internally and externally while the installation is in drydock or at the time of underwater examination in lieu of drydocking, and the fastenings to the shell plating are to be renewed when considered necessary by the Surveyor.

(B) Pumps and pumping arrangements, including valves, cocks, pipes, and strainers, are to be examined.

(C) Nonmetallic flexible expansion pieces in the main salt-water circulating system are to be ex- amined internally and externally.

(D) The Surveyor is to be satisfied with the operation of the bilge and ballast systems. Other

systems are to be tested as considered necessary.

(E) The foundations of machinery are to be examined.

(F) Heat exchangers and other unfired pressure vessels with design pressures over 0.7 MPa are to be examined, opened out or thickness gauged and pressure tested as considered necessary, and associated relief valves proven operable.

(3) Electrical Parts to be Examined

(A) Fittings and connections on main switchboards and distribution panels are to be examined.

Guidance for Floating Production Units 2015 23

Ch 2 Classification and Surveys Ch 2

(B) Cables are to be examined as far as practicable without undue disturbance of fixtures.

(C) All generators are to be run under load, either separately or in parallel; switches and circuit breakers are to be tested.

(D) All equipment and circuits are to be inspected for possible development of physical changes or deterioration. The insulation resistance of the circuits is to be measured between con-

ductors and between conductors and ground and these values compared with those pre-

viously measured. Any large and abrupt decrease in insulation resistance is to be further in- vestigated and either restored to normal or renewed as indicated by the conditions found.

(F) The specified electrical auxiliaries for vital purposes, generators and motors are to be exam-

ined and their prime movers opened for inspection. The insulation resistance of each gen- erator and motor is to be measured.

(G) The accumulator batteries are to be examined, including their maintenance schedule and the

society reviewed procedure of maintenance.

(H) Bilge alarm system, if fitted, is to be tested and proven satisfactory.

(I) Non-explosion proof electric motors are to be examined, including automatic power dis- connect to motors that are arranged to shut down in case of loss of ventilation.

(4) Surveys of machinery that has been accepted for surveys based on preventative maintenance techniques are to comply with the requirements of Pt 1, Annex 1-8 of Guidance relating to

the Rules for the Classification of Steel Ships.

(5) On self-propelled installations, in addition to the requirements for Annual Survey and the appli- cable requirements of above (2), the main and auxiliary machinery are to be surveyed in ac- cordance with the requirements of Pt of Guidance relating to the Rules for the

Classification of Steel Ships as applicable to self-propelled vessels.

5. Inert Gas Systems

Surveys of dynamic positioning systems are to comply with the requirements of Pt 1, Ch 2, Sec 5-1, Par 1 of Rules for the Classification of Steel Ships.

6. Dynamic positioning systems (if relevant notations are assigned)

Surveys of dynamic positioning systems are to comply with the requirements of Pt 9, Ch 4 of

Rules for the Classification of Steel Ships.

7. Production systems (if relevant notations are assigned)

(2) Internal examination of pressure vessels, pumps, compressors, and safety relief valves

(3) Random thickness gauging of process piping, as considered necessary

(4) Hydrostatic testing of process related piping systems to 1.25 times the maximum allowable working pressure as considered necessary.

(5) Lube oil examination record review

(6) Measurement of the insulation resistance of generators and motors ix) Running of generators of under load, separately and in parallel

(7) Examination of cable runs, bus ducts, insulators, etc.

(8) Testing of circuit breakers, relays, etc.

(9) Examination of electrical equipment and circuits for possible damage or deterioration

(10) Vibration checks of rotating machinery

(11) Internal examination of steam and gas turbines, as considered necessary

(12) Testing of protective devices for engines, turbines, and gas compressors

(13)

Internal examination of diesel engines and gas engines rated 1000 hp output and above, as

considered necessary

(14) Operational check of process control equipment.

8. Import and export systems (if relevant notations are assigned)

Special Survey is to include all items listed under the Annual Survey and, in addition, the follow- ing are to be performed. However, survey items may modified according to types of import and export systems. Operators and designers may submit alternative survey requirements based either on

24 Guidance for Floating Production Units 2015

Ch 2 Classification and Surveys Ch 2

service experience or manufacturer’s recommendations. Upon review, these alternative survey proce- dures may accepted by the Society.

(1) Fluid and electrical swivels are to be disassembled, if considered necessary, and examined for

wear and tear. The seals are to be examined. Upon completion of the reconditioning, the fluid swivels are to be hydrostatically tested. Similarly, the electrical swivels are to be insulation test- ed upon reassembly.

(2) During underwater inspection of the SPM system, flexible risers are to be examined, including all arch support buoyancy tanks. Risers are to be inspected for damage in high stress areas, such as areas in way of the end flanges, areas in way of the arch support clamps and the bot- tom of all looped areas. Spreader bars, if fitted to separate one riser string from another, are to be inspected for wear and tear. Hydrostatic tests may be required to be conducted on the risers, as deemed necessary by the Surveyor.

(3) For deep sea applications, riser suspension or support systems are to be examined for deterio- ration and loss of tension. Support areas in way of the riser are to be closely examined for fretting corrosion, wear, kinks, creases, etc.

(4) Floating export hoses are to be examined for kinks, surface cracks, chafing damages, etc.

Hydrostatic and vacuum tests may be required to be conducted on the floating hose string, as deemed necessary by the Surveyor.

(5) All piping systems are to be opened up for examination. Nondestructive and hydrostatic tests may be required, where considered necessary by the attending Surveyor.

(6) For disconnectable type mooring systems, the disconnect and connect arrangements for the im-

port and export systems are to be tested, as considered necessary by the Surveyor. Alternatively, records of disconnect/connect operations between the credit date of the last SPS and the current due date of same may be reviewed, and if found satisfactory, it may be considered to have complied with this requirement.

(7) Hoses designed and manufactured based on OCIMF standards are to be tested in accordance with the "OCIMF Guide for the Handling, Storage, Inspection, and Testing of Hoses in the

Field".

305. Docking Survey

The underwater parts of a unit are to be examined at certain intervals. This examination may be conducted by In-water Survey in lieu of drydocking or, if necessary, a survey on drydock. During this survey, the Surveyors are to survey the unit, its structural condition, corrosion protection sys- tem, mooring system and(if classed) the import and export systems.

1. Due range

(1) There is to be a minimum of two Docking Survey during each five-year Special Survey period.

One such Docking Survey is to be carried out in conjunction with the Special Survey. In all cases the interval between any two such Docking Surveys is not to exceed 36 months.

(2) Consideration may be given for extensions of rule-required Docking Survey under exceptional

circumstances. An In-water Survey may be required for such extensions.

2. Requirements of survey

(1) For ship type and barge type units, the following items are to be examined, as applicable: The keel, stem, stern frame, rudder, propeller, and outside of side and bottom plating are to be cleaned as necessary and examined, together with bilge keels, thrusters, exposed parts of the stern bearing and seal assembly, sea chest, rudder pintles and gudgeons, together with their re- spective securing arrangements. All sea connections and overboard discharge valves and cocks, including their attachments to the hull or sea chests, are to be externally examined. All non- metallic expansion pieces in the sea-water cooling and circulating systems are to be examined both externally and internally. The stern bearing clearance or weardown and rudder bearing clearances are to be ascertained and reported on.

(2) For column-stabilized units, the following are to be examined:

(A) External surfaces of the upper hull or platform, footings, pontoons or lower hulls, under- water areas of columns, bracing and their connections, as applicable, are to be selectively cleaned and examined. These areas include joints of critical structural members, areas sus-

ceptible to damage from offshore support vessels, anchor chains, dropped equipment, corro-

sion and erosion from loss of coating, or sand scouring and areas of progressed and accu- mulated wear-and-tear.

Guidance for Floating Production Units 2015 25

Ch 2 Classification and Surveys Ch 2

(B) Nondestructive testing may be required of areas found to be suspect. Joints of different con- figurations of major structural members are to be selected, cleaned and magnetic particle inspected. The selection of these joints are to be such that all joints underwater are to be inspected every five years.

(D) External portions of propulsion units are to be examined, if applicable.

(E) The type, location and extent of corrosion control(coatings, cathodic protection systems, etc.), as well as effectiveness, and repairs or renewals to same should be reported in each survey. Particular attention is to be given to corrosion control systems in ballast tanks, free-flooding

areas and

(F) All tanks gas freed

other locations subjected to sea water from both sides.

and voids that are to be internally examined are to be thoroughly ventilated and prior to being entered and are to be carefully monitored for pocketing or emis-

sions of hazardous gases during examination.

(G) In conjunction with Docking Surveys(or equivalent In-water Surveys), the following ballast tanks are to be internally examined, and the effectiveness of coatings or corrosion control arrangements are to be verified either visual inspection or by thickness gauging(as consid- ered necessary), placed in satisfactory condition, as found necessary, and reported upon:

(a) Representative ballast tanks in footings, lower hulls or free-flooding compartments, as ac- cessible

(b) At least two ballast tanks in columns or upper hull, if applicable

(3) Corrosion prevention system - underwater body

In addition to the above (1) and (2) requirements, the following are to be to be performed dur- ing all of the Docking Surveys(or equivalent In-water Surveys):

(A) Cathodic potential readings are to be taken from representative positions on the entire under-

water body and evaluated to confirm that the cathodic protection system is operating within design limits.

(B) Sacrificial anodes are to be examined for depletion and placed in satisfactory condition, as

considered necessary.

(C) Impressed current system anodes and cathodes are to be checked for damage, fouling by marine growth and carbonate deposits. The current and voltage demands of the system are to also be checked to ensure the system is functioning properly.

(D) Additional examinations are to be performed on the wind and water areas of the structures

where coating breaks are evident. Thickness measurements in these areas may be required if found necessary by the attending Surveyor.

(4) Mooring system

For mooring systems, the following are to be cleaned and examined, where applicable:

(A) The mooring anchor chain or cable tensions are to be measured and the end connections of these components are to be examined. All mooring chains are to be generally examined for their entire lengths.

(B) Anchors, cables and their respective handling means are to be examined.

(D) Chain and stopper assemblies are to be cleaned, examined and NDE performed, as consid- ered necessary by the Surveyor.

(E) Areas of high stress or low fatigue life are to be preselected, cleaned and NDE performed, if considered necessary.

(F) Scour in way of anchors or anchor piles is to be examined.

(G) Cathodic potential readings are to be taken from representative positions on the entire un- derwater structure of the mooring system to confirm that the cathodic protection system is operating within design limits.

(H) Highly stressed, high wear and tear areas of the mooring chain are to be closely examined and nondestructively tested, if considered necessary by the Surveyor. These include areas in way of the stoppers and sea bed touchdown areas.

(5) Import and export systems (if relevant notations are assigned)

(A) For import systems, the following are to be cleaned and examined, where applicable:

(a) The entire riser system.

(b) The arch support buoyancy tanks, their structures and the clamping devices.

(d) Hoses designed and manufactured based on OCIMF standards are to be tested in accord- ance with the "OCIMF Guide for the Handling, Storage, Inspection, and Testing of

26 Guidance for Floating Production Units 2015

Hoses in the Field".

(B) For export systems, the following are to be cleaned and examined, where applicable:

(a) The entire export flexible system is to be examined for damage due to chafing and fa- tigue fractures.

(b) Hoses designed and manufactured based on OCIMF standards are to be tested in accord-

ance with the "OCIMF Guide for the Handling, Storage, Inspection, and Testing of Hoses in the Field".

3. In-water Survey

(1) For units with IWS notation in accordance with relevant requirements specified in Pt 1, Ch 2, 604. of Rule for the Classification of Steel Ships, an approved In-water Survey by a diver may be considered equivalent to a Docking Survey, up to and including Special Survey No. 4. The In-water Survey Procedures in accordance with Ch 2, Sec 3, 309. of Rules for the Classification of Mobile Offshore Drilling Units are to be submitted for review and approval in advance of the survey.

This approved procedure is to be made available onboard. In addition, the inspection procedures

are

to also consist of the following:

(A) Scope of inspection

(B)

(C)

Procedure for divers to identify the exact location at which they are conducting their in-

spection

Procedure for cleaning the marine growth for inspection purposes that is to include the ex- tent and location of the underwater cleaning

(D) Procedure and extent for measuring the cathodic potential readings in way of the structures

(E)

Procedure and extent for taking thickness measurements of the structures and NDE of crit- ical joints

(F) Qualifications of all divers conducting the inspection, NDE and thickness measurements

(G) The type of underwater video and photography, including means of communication, monitor- ing and recording

(H) For In-water Surveys in lieu of Docking Surveys associated with Special Survey, means are to be provided to permit the opening up of all sea valves and overboard discharges for in-

ternal examination. In addition, all Special Survey items related to the underwater portion of

the hull or structure, including the thickness measurement requirements are to be dealt with during the In-water Survey.

(2) For each In-water Survey in lieu of Docking Survey after Special Survey No. 4, requests to

conduct an In-water Survey are to be submitted for consideration well in advance of the pro- posed survey. Approvals to conduct the In-water Survey in lieu of Docking Survey after Special Survey No. 4 are to be made available onboard for the Surveyor's reference.

306. Tail Shaft and Tube Shaft Surveys

For Tail Shaft Surveys of self-propelled units, applicable requirements of Pt 1, Ch 2, Sec 7 of Rule for the Classification of Steel Ships are to be complied with. However, due to low run- ning hours on tail shafts of units, the interval between tail shaft surveys may be extended based on the following being performed to the satisfaction of the Surveyor:

(1) Diver’s external examination of stern bearing and outboard seal area, including weardown check as far as is possible.

(2) Examination of the shaft area (inboard seals) in propulsion rooms.

(3) Confirmation of lubricating oil records (satisfactory oil loss rate, no evidence of unacceptable contamination).

(4) Shaft seal elements are to be examined/replaced in accordance recommendations.

with seal manufacturer’s

307. Boiler Surveys

Boiler Surveys are to comply with the requirements of

Classification of Steel Ships.

Pt 1, Ch 2, Sec

8 of

Rule for the

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