OTM-7.19	Oil Tanker Manual OTM Ship to Ship Transfer	Doc No.: OTM 7.19 Revision: 01 Date: 15 Oct 2024 Issued by: DPA Approved by: MD

1. APPLICATION

This document applies to the Master and Deck Officers onboard fully managed tank vessels.

2. PURPOSE

To specify standard requirements for ship-to-ship transfer operation. Under the scope of this procedure, bunkering / de-slopping operations are not considered as STS operations.

3. REQUIREMENT

Carriage of STS operation plan written in the working language of the ship is mandatory for oil tankers engaged in STS operation under the following regulations:

• MARPOL Annex –I, Chapter 8 - Prevention of Pollution during Transfer of Oil Cargo between Oil Tankers at Sea
• Regulation 41 & IMO Resolution MEPC.186 (59)
• 33 and 46 CFR (applicable sections) – (For operations in USA)

4. RESPONSIBILITIES

Master:

• To ensure STS operation is carried out in accordance with STS Plan, OCIMF STS transfer guide, Tanker safety guide (chemicals, Liquified gas), Liquified Gas handling principles, ISGINTT, Mooring Equipment guidelines & ISGOTT
• 33 and 46 CFR (applicable sections) – (For operations in USA)
• Notify relevant authorities
• Liaise with mooring master / POAC (Person in Overall Advisory Control)
• Under no circumstances is the master to permit safety or environmental protection to be jeopardized by the orders or actions of the mooring master / POAC, customer representatives or other personnel involved in the lightering operation.
• In all circumstances, the master is solely responsible for safety and proper navigation of his ship and for all aspects of cargo operations.
• Master must ensure integration of the mooring master / POAC into his bridge team, such that a proper navigation watch is always kept, whether anchored, steaming, or drifting. This includes monitoring traffic using all available means.

Chief officer

• Should be familiar with and have an understanding of STS Plan, OCIMF STS transfer guide & ISGOTT
• Coordinate with Master for mooring operation
• Prepare cargo plan
• Comply with STS transfer checklists

Deck officers

• Assist Master & Chief officer during STS operation
• Should be familiar with and have an understanding of STS Plan, OCIMF STS transfer guide & ISGOTT

Mooring master / POAC

• STS operations shall be controlled by a suitably qualified and experienced mooring master / POAC as recommended by the STS transfer guide.
• He would advise and provide guidance on the lightering operation including mooring/unmooring plan, communications, safety advice and transfer advice, to both the master of the SV and the STBL.

Marine Superintendent

• He should screen the proposed vessel and to the minimum following documents should be requested for clearance:
• Expected date of STS operation
• Location of STS Operation
• Details of cargo
• Details of instructions from operators
• Q88, latest class survey status report, STS approval page, P&I Certificate, H&M Certificate, CLC of vessel(s) in question
• On successful clearance of the proposed vessel to advise acceptability to Charterer and vessel.
• Final approval to be given to vessel based on detailed risk assessment and completed STS01- Ship to ship transfer questionnaire.

5. DEFINITION

• Lightering (33CFR156.205): The transfer of cargo of oil or hazardous material in bulk from one vessel to another, including all phases of the operation from the beginning of the mooring operation to the departure of the service vessel from the vessel to be lightered.
• Service Vessel (SV): The manoeuvring of the lightering vessel, which will receive the cargo from the ‘mother vessel’ or ‘ship to be lightered’ (STBL) and transport the cargo to its discharge berth. The mooring master / POAC will always be on board the service vessel.
• Ship to be Lightered (STBL): The ‘mother vessel’ normally a Suezmax, VLCC, or ULCC, that requires lightering offshore.
• Reverse Lightering: Sometimes referred to as ‘topping-off’, a lightering operation in which a loaded service vessel transfers cargo to a part-loaded Ship to be lightered (STBL).

6. GENERAL

6.1 Notification

Any oil tanker that plans STS operations within the territorial sea or the EEZ of a party to MARPOL, shall notify the relevant coastal state party not less than 48 hours in advance of the scheduled STS operations. The notification shall include at least the following:

• Ship's Name, Call Sign, IMO Number
• ETA
• Geographical location at the commencement of the planned STS operations
• Whether STS operations are to be conducted at anchor or underway
• Oil type, quantity
• Duration of operation

6.2 Ship-to-Ship Communication

• A VHF channel shall be agreed upon and guarded for radio communication between the ships and workboat. Portable radios may also be used for communication.
• During transfer operation, medium and high-frequency radio systems shall not be operated. Only intrinsically safe portable communication equipment shall be used on deck.
• If communication breakdown occurs between vessels during an approach manoeuvre, the manoeuvre should be aborted if appropriate and safe to do so.
• If the communication breakdown occurs between vessels during the cargo transfer operations, the emergency signal shall be sounded, and all operations suspended immediately if safe to do so. The operation shall resume only after communication is restored.

6.3 Lightering Rendezvous Locations

• The ship should establish initial communication as early as practicable to plan operation and to confirm the transfer area.
• The lightering rendezvous location may be advised on the charterer’s preference and agreement. Lightering must not be conducted within 1.5 miles of offshore structures or mobile drilling units.
• Operations in the USA should be carried out in the areas recommended in CSR. The master shall take caution not to carry out any ship-to-ship operations in prohibited areas. USCG regulations prohibit lightering within 20 miles of shore without permission of the USCG Captain of the port.

6.4 Anchoring during STS Operations

• Lightering and anchoring over pipelines, fish havens, or historical resources is prohibited.
• The mooring master / POAC and master of each ship should review and agree if anchoring is appropriate considering:
  • Navigational restrictions
  • Traffic in the vicinity
  • Weather and sea state
  • Anchoring location must consider proximity to underwater pipelines, oil rigs/platforms, and traffic schemes.

6.5 Transshipment of Cargo with Barges in Port Limits / Double Banking at Berth

• Normally, transshipment operations in port are carried out after the port carries out pre-approval of barges and the barge will only be able to enter the port if all certificates are valid. Hence, pre-approval of the nominated barges will not be required to be carried out by the Marine department.
• Following procedures should be followed by Masters:
  • Liaise with the charterers/commercial operator on what screening process was employed to ensure the statutory class certificates and insurance documents are valid.
  • Request charterers agents to provide the barge particular questionnaire or Q88 or any document that will provide particulars of the barge.
  • Request charterers agents to provide proof of insurance or any document that will confirm the third-party insurance coverage of the barge.
  • Request certification of inspection (for barges operating in the USA) or any other certificate issued by the barge's flag or class.
• Additionally, Masters should conduct a thorough STS review when the barges are coming alongside each other to check that the number of mooring ropes/wires that will be provided by the barge are in visibly good condition and the fendering equipment available and proposed for transshipment is in good condition.
• Ensure the following checklists are completed:
  • STS Form 01H – Mooring & Unmooring of Barge
  • STS Form 01I – STS in Port Pre-transfer Checklist
  • STS Form 01J – STS in Port During Transfer Checklist

6.6 Electrical Safety

• Earth indicator lights on the main switchboard indicate a faulty circuit. Such faults when detected on board shall be immediately traced and rectified, especially in deck areas where hazardous accumulations of gas may be present.
• To avoid electrical arcing between ships, adequate insulation shall be used between ships (Insulating flange, hose, etc.).
• The conventional hoses, which are in use, are not insulating type, and this may be confirmed with the certificate or by testing them on board.
• In the absence of insulation between ships, electrical potential between them should be reduced as much as possible. If both ships have an impressed current cathodic protection system, this should be left running. If one of the ships has impressed current and the other with sacrificial anode system, then the former should be left running.
• If either ship is without cathodic protection or its impressed system has broken down, then the impressed current system on the other vessel shall be switched off.

6.7 Helicopter Operations

• Helicopter operations must be conducted in compliance with OCIMF and ICS guidelines. Helicopter operations are prohibited during cargo operations.
• Cargo transfer must be stopped during helicopter landing, take-off, and as long as the helicopter engines are operating if it lands on the deck.
• Efficient communication must be established with the helicopter during the operation.

6.8 Work / Rest Hours and Fatigue

• Fatigue is the cause of human error because of its impact on performance. To prevent fatigue during STS operations, all the crew involved in the lightering operations should comply with rest period requirements of relevant ILO, IMO, and national regulations.
• When multiple lightering operations are done, the master shall take the necessary steps to ensure rest hours are efficiently managed on board for safe operations.

6.9 Personnel Transfer

• In general, it is recommended that the transfer of personnel between ships be kept to an absolute minimum.
• Gangways should only be used where there is little or no movement of the ship. If used, gangways should be fitted with rails and complete with a safety net and should be tended to ensure they always remain within safe design operating parameters. The use of open-rung ladders is not permitted.
• Where workboat transfers take place using appropriate pilot ladder/accommodation ladder combinations, due account should be taken of the freeboard. Due consideration should be given to sea conditions, suitability of the workboat, and experience/fitness of transferring personnel.
• Prior to commencing personnel transfer using a Personnel Transfer Basket (PTB), it should be ensured that the PTB is suitable for the task, certified, tested, and inspected, and the associated lifting equipment is suitable for personnel transfer.

Note:

• Refer to STS Form 01F - STS personal transfer by crane and STS transfer guide Section 9.4 & 9.5
• An officer shall attend to the transfer operation.
• Personnel transfer baskets are not to be used for transferring any stores or other heavy materials.

6.10 Safety Drills

Master and ship’s crew should prepare to mitigate emergencies by conducting drills/training prior to conducting STS operations.

6.11 Weather Operating Conditions

The vessel shall obtain weather reports in advance and ascertain if the weather would remain favorable for the planned period of STS operation. Weather should be monitored by all available means.

6.12 Maximum Operating Conditions

• It is impracticable to lay down limiting weather conditions under which STS operations can be carried out because much will depend on the effect of the sea and swell on the fenders or mooring lines and the rolling movements included in the participating ships, considering their relative freeboard and displacement.
• In making the mooring decision, good judgement shall be used by Masters of both vessels considering the advice of the mooring master / POAC in deciding if conditions are acceptable to conduct operations. STS operations in the vicinity of long period swell should be treated with caution.
• USCG regulation (33 CFR 156.320) prohibits lightering operations when the following maximum operating conditions are exceeded:
  • Mooring should not be attempted when the following parameters are in effect:
    • Wind velocity of 56 km/hr (30 knots) or more
    • Wave height of 3 meters (10 feet) or more
    • Swell of short or average length, height of 10 feet or more
  • Cargo transfer operations should be stopped, and hoses drained when the following parameters are in effect:
    • Wind velocity of 82 km/hr (44 knots) or more
    • Wave heights exceed 5 meters (16 feet)
• Ships moored should unmoor if weather and/or sea conditions create unsafe conditions. Examples include increasing danger of ships making contact, hose stretching excessively, rupture of fenders, or breaking of wires securing fenders.
• The transfer operations may be carried out while drifting or slow steaming in the event of slight weather and sea conditions. Transfer at anchor is suitable only in extremely good weather conditions with low wave height. Combined current and weather effects would cause yawing movements and excessive strain on the moorings and anchor.

6.13 Navigational Warnings

• The Master shall ensure that appropriate navigational warnings are sent out as per the applicable local regulations. All the vessels in the vicinity shall be notified of the intended operation.
• For vessels operating in US waters, please refer to CFR 156, 160, etc. for reporting guidelines. The workboat or the vessel shall send the ‘SECURITE’ warning on VHF channel 16 prior to the commencement of operations and cancel the warning upon completion (unmooring).

6.14 Lights and Shapes

• Lights and shapes are to be displayed as per COLREGS.

By Day

• Restricted in ability to manoeuvre shape: ball-diamond-ball (black) hung in a vertical line.

By Night

• Restricted in ability to manoeuvre lights: red-white-red in a vertical line.

6.15 Fenders and Rigging

• Appropriate fenders should be used for all STS operations. The size and specification for the fenders should be as recommended in the STS transfer guide.
• Primary fenders are positioned along the parallel body of the ship to afford the maximum possible protection while alongside.
• Secondary fenders are used to protect the bow and stern plating from inadvertent contact if the ships get out of alignment. The contacts where such contact is likely to occur should be identified and secondary fenders shall be positioned. The position should be changed during the operation and before unmooring due to likely change of contact points due to changes in freeboard.
• The mooring master / POAC shall advise the positioning and rigging procedures for the fenders. The Master shall ensure that the fenders are of the recommended size and number and correctly positioned for the intended purpose.
• If the vessel carries its own fenders, the fenders and accessories shall be maintained as per the planned maintenance system on board.

6.16 Cargo Transfer Hoses

• The cargo transfer hose must be checked for suitability and have a test certificate to prove its reliability for the intended operation. It should not form permanent kinks or separate the internal liner.
• Care must be taken to avoid over-bending or twisting of the hoses. The key to preventing damage is handling with adequate support.

Note:

• For guidance on Cargo transfer hoses refer to STS Transfer guide Section 9.2
• The maximum rate of transfer must be agreed upon between both vessels with the advice of the mooring master / POAC. In any case, the maximum transfer rate/velocities shall not exceed the rated capacity of the hoses.

Note:

• Flow rates for different hose velocity ranges can be calculated using the following formula:
• (𝜋𝑟2𝑣 × 3600 = 𝑐𝑢𝑏𝑖𝑐 𝑚𝑒𝑡𝑟𝑒𝑠 𝑝𝑒𝑟 ℎ𝑜𝑢𝑟) Where ‘r’ is the internal radius in meters and ‘v’ is flow velocity in meters per second.
• Irrespective of the designed maximum flow velocity of the hose, consideration should be given to any flow restrictions posed by other equipment, such as valve linings.
• Hose strings should be of sufficient length to avoid over-stressing and chaffing. Manifold height relative to each ship should be monitored throughout the transfer operation, and each ship should ballast or de-ballast to maintain minimal difference in freeboard.
• Throughout cargo transfer, hoses should be supported by the provided slings and hose saddles using the ship's crane / derrick on both ships.
• Hose should not be lifted from a single flange. When connecting hoses, the hose should not be twisted.
• The hose is supported by ropes at each flange, which should be secured to cruciform bits on the deck of each ship, at the ship's rail to help support the hose and assist in drainage. Hoses in service may not be completely drained of oil and may have residual pressure. Due consideration should be made of the weight of hoses, and flanges should be opened carefully to prevent injury or pollution.
• While making the connection, ship crane / derrick should be used to minimize the movement of the hose. The hose should be laid between the two vessels in a loop without kinks. Offsetting each vessel's manifold while mooring may improve the catenaries of the hoses.

Note:

• A thumb rule for calculating the minimum bending radius (MBR) of a rubber hose is:
• MBR = Nominal Bore of hose x 6
• (For e.g., a hose of 12 inches nominal bore will give a minimum bending radius of approximately 72 inches).

Coution:

• The hoses used for handling LPG / LNG should be specially designed and constructed for the product, maximum pressure and minimum temperature expected.
• Refer to STS Transfer guide Appendix C 9.2 for LPG & Appendix D 9.2 for LNG.
• The hose should be above the fenders and fender securing wires so there is no danger of the hose pinching between the two ships. Blank flanges shall be fitted to hoses when not connected to the manifold. Bolts shall be used in each hole.
• A ship officer shall be at the manifold during hose connecting, disconnecting, and draining. A crew member shall be stationed near the manifold throughout the transfer on each vessel to monitor the hose, connections, and manifold area for leaks.
• Should a leak develop, the cargo transfer must be immediately stopped, and the emergency alarms sounded.
• If the vessel carried and uses its own hoses, the hoses shall be tested every 12 months and tests recorded in CCR33. Hoses should be visually inspected for tears or damage prior to each use.

7 STAGES OF OPERATION

Stage 1 - Prior Arrival

• Ensure STS Form 01A - STS “Pre-Fixture information” is completed by ship operators & managers.

Stage 2 - Arrival

• Ensure compliance with STS Form 01B - STS “Before operations commence.”

Stage 3 - Approach and Mooring

• Ensure compliance with STS Form 01C - STS “Before run in and mooring.”
• The manoeuvring approach and mooring plan shall be discussed and agreed between the mooring master / POAC and master of both vessels.
• Both the SV and STBL shall have a helmsman, with each ship in hand steering during approach and mooring operations.
• Masters should agree regarding acceptable weather conditions before commencement of lightering operations.
• In reverse lightering operations, due consideration should be given to the reduced manoeuvring capability, slower response, and additional forces of a laden tanker. Extra caution should be observed because of the increased mass of the manoeuvring vessel.
• Relative approach speeds (transverse speed) exceeding 0.6 knots could result in excessive force / compression of the fenders, leading to fender failure and subsequent collision of the two ships. The approach should be aborted if these conditions cannot be met.
• All moorings and fender wires must be kept well lubricated and tended throughout the lightering operation.
• Masters should be prepared to abort berthing operations if necessary.
• STS during hours of Darkness.

Double Banking

• This operation involves one or more vessels mooring alongside a ship that is already moored to a jetty.
• Before double banking operations are agreed, the following should be considered:
  • Safe arrival and departure procedures.
  • Integrity of the berth, including fender panels and mooring fittings, with regard to the potential loads involved.
  • Personnel access, including emergency escape provisions for personnel on all involved ships.
  • Management of operational safety.
  • Roles and responsibilities of involved parties.
  • Contingency planning, fire-fighting, and emergency unberthing.
• Master of the ship alongside the terminal should be aware of the total displacement of his ship and vessel berthing alongside. The mooring arrangements should be adequate for the anticipated loads.
• Consideration should be given to line handling support. The ship alongside the terminal may provide crew to receive and secure the line but this should not detract from the safety of any ongoing cargo operations.

Stage 4 - Cargo Transfer

• Ensure compliance with STS Form 01D - STS “Before Cargo Transfer.”
• Cargo transfer operations should be conducted under closed conditions with the cargo tanks on both service vessel (SV) and the ship to be lightered (STBL) inerted if applicable, with due regard to safe tanker practices and in compliance with applicable law and regulations.
• Both SV and STBL must maintain their engines in a state of readiness, throughout the entire lightering operation, so that emergency manoeuvring can be carried out if needed.
• Navigation and deck watch shall restrict unauthorized craft from approaching/coming alongside while engaged in lightering operations.



Note:

• Bridge watch to be maintained when own ship is at anchor. When another ship is at anchor, prior taking over the watch duty officer to ensure another vessel is holding ground.


• Only pre-authorized vessels with spark arrestors on the exhaust shall be permitted alongside during lightering operations.
• No cargo transfer operations may be conducted during electrical storms.
• During cargo operations, each ship shall keep its fire system ready for immediate use.
• Both SV and STBL must maintain a deck watch and watch near their respective manifolds. Should leakage occur, oil observed on the water, hoses become constricted or stretched excessively due to ship movements, or other unplanned events occur that present a threat to oil spill, the cargo transfer operations must stop, and each ship should secure its manifold valves until investigation and mitigation action taken.
• Should either ship find safety precautions are not being observed on either ship, operations shall be suspended until deficiencies are corrected.
• In the event of gas accumulation on deck, cargo transfer operation should be stopped and should not resume until the risk to personnel and vessels has been controlled.
• Masters of both ships should be prepared to un-moor if necessary.
• Should 2 or more mooring lines or tails part in succession, cargo transfer should be stopped, and hoses drained until mooring lines/tails have been replaced and also weather conditions have been reviewed.
• At hose disconnect, the manifold on the ship with the highest freeboard should be closed and the hoses drained into the ship with the lesser freeboard. On hose disconnect, open flanges must be blanked.

Stage 5 - Unmooring

• Ensure compliance with STS Form 01E - STS “Before Unmooring.”
• All cargo systems must be secured. Unmooring plan shall be discussed with the mooring master / POAC.

For personal transfer, refer to STS Form 01F - STS personal transfer by crane. For vapour balancing, refer to STS Form 01G - STS involving vapour balancing.

• For pre-transfer in port, refer to STS Form 01I – STS in Port Pre-transfer checklist.
• For during transfer in port, refer to STS Form 01J – STS in Port during transfer checklist.

Stage 6 - Review of STS Operation by Master

• On completion of STS Operation, once the unmooring operation is over, the Master must do a proper review of the STS operation and report to Officer (MS with VM in copy) with his assessment and feedback on the completed STS operation using the STS Form 01K.

8 REFERENCED FORMS AND CHECKLISTS

• STS Form 01 – Ship to ship transfer questionnaire.
• STS Form 01A – STS pre-fixture information.
• STS Form 01B – STS before operations commence.
• STS Form 01C – STS before run in and mooring.
• STS Form 01D – STS before cargo transfer.
• STS Form 01E – STS before unmooring.
• STS Form 01F – STS personal transfer by crane.
• STS Form 01G – STS involving vapour balancing.
• STS Form 01H – Mooring & Unmooring of Barge.
• STS Form 01I – STS in Port Pre-transfer checklist.
• STS Form 01J – STS in Port during transfer checklist.
• STS Form 01K – Ship to ship Transfer [Feedback/ assessment by Master after operation].