Ship To Ship (STS) transfer operations plan

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With reference to new IMO RESOLUTION MEPC.186(59), adopted on 17 July 2009, a new STS PLAN will be mandatory for all oil tankers above 150 GT. Emphasis is given on the follow up and retained records on board a fact which constitutes a due diligence scheme for effective and safe STS operations.

Oceanic Technologies can produce STS Plans customised to meet the specifications and operating characteristics of every vessel in accordance with the latest international standards and regulations.

We have a respectable experience in STS procedures and policies as well as the Due diligence implementation. We undertake to deliver the STS plan approved by the administration or RO’s (subject to prior confirmation and acceptance from the owners) along with outlined instructions for implementation and associated software.

The STS plan produced will be supported with an online web page that will focus on the requirements of International Regulations as well providing useful assistance to those participating in STS operations via an online monitoring system. Our STS Plan has the advantage that is accompanied with a free subscription at the ONLINE STS web site for all our customers.

The web site will offer a free subscription as well as a fee subscription subject to the requested services from the owners. Please find outlined below the benefits and services from the web site:

1. You will be able to read STS associated updated information (free).
2. You will be able to see the updated rules and restrictions from coastal authorities (free).
3. You will be able to create/ monitor and inform all associated parties with each individual STS operation (free).
4. You will be able to see information related to STS operators, Response organizations, STS equipment (free).
5. You will be able to download STS plan upgrades by simply using the IMO number of each vessel (free).
6. You will be able to perform Screening analysis as well as risk assessment for STS operations (under a fee)

If you are interested, please use the contact button, fill in the form and we will get in touch with you.

Ship To Ship (STS) transfer operations, general information.

Transshipment of oil or gas between seagoing tankers (Ship To Ship transfer or STS) is a common practice. It was widely used in the 60s with the introduction of lightering operations, when the dimensions and particularly the draft, of the new and large tanker vessels (the so called super tankers) did not allow them to approach ports in fully laden condition. Nowadays however, this practice is more often used during the transshipment and distribution of liquid cargo (Oil and associated products) for optimization purposes.

The term Ship To Ship transfer applies to all cargo transfer operations between two seagoing ships and includes the lightering process, which takes place when large tankers are discharging their load into smaller and more flexible tankers. Normally in a typical STS operation the cargo transshipment occurs from a big loaded tanker to a smaller and empty tanker. Nevertheless, sometimes the process is carried out reversely (Reverse STS operation), from a fully loaded small tanker to a bigger partially loaded tanker.

The parties involved in STS operations are:

• The two ships and their masters
• The ship owners,
• The charterers,
• The cargo owners
• The STS operator company, which will normally provide the mooring master and the necessary equipment (i.e. fenders, hoses, etc.). However in some cases one of the two captains can act as mooring master.

The mooring master assists the approach and mooring of the two ships, using the equipment provided by the STS operator company. The final responsibility is taken by the masters, as always, however all parties involved must do their best to ensure the safety of life and environment.
STS of oil or natural gas, is a high-risk undertaking and includes risks with large-scale financial and ecological consequences. This stems mainly from the nature of oil and gas, but also from the fact that the involved ships are exposed to weather conditions while having limited maneuverability.
Furthermore, other involved parameters, such as the required specialized equipment, the compatibility of participating ships, and the experience of the crew and mooring master will play a decisive role.
For the safe conduct of STS operations precautions must be taken, including personnel training, careful selection of the area where STS will take place and the continuous observation of weather conditions (ICS / OCIMF, 2005; ICS / OCIMF, 1995).
The management of the above mentioned parameters, as well as the STS operation itself is a critical task.

What is the STS PLAN?

The STS Plan is documentation which has to be on board each oil tanker and incorporates information associated with the following:

• Personnel resources, drills and familiarization,
• Vessel characteristics and STS associated gear.
• STS operations guidelines
• Emergency preparedness plan and procedures
• STS checklists and filling documentation
• Assessment and reporting procedures.

The STS Plan has to be prepared and submitted to the administration for approval no later than the first annual survey from 01/01/2011.

General Principles

All Ship To Ship Transfer Operations (STS) must be exercised in accordance with good seamanship practices, the latest safety standards and relevant regulations/guidelines issued by the International Organisations (IMO, ICS, OCIMF, etc.) Additionally all the personnel involved must be skilled and properly trained. In conclusion the general principles of the STS plan are:

1. Description of STS Operation and general safety issues
2. The role of the person in overall advisory control of STS operations
3. The role of the participants in STS operations
4. Emergency preparedness Plan.


The STS plan incorporates step by step guidelines for the conduction of STS operation customized to the match the particulars of each vessel. An organization chart assigns the necessary positions and prescribes personnel duties. General principles are customized to match the available equipment and personnel and where applicable, safety standards are interpreted to specific limits. A brief analysis is as follows:

1. Personnel Recourses. Organization Chart and Training.
2. Equipment. Availability and inspection.
3. The role of the STS operator and Masters Responsibility.
4. Procedures for STS Operations
a. Communication
b. Approaching
c. Mooring
d. Procedures alongside
e. Unmooring
f. Safety and Emergencies.
5. Procedures and Policies for STS Operations
a. STS Location (Coastal State, Weather conditions, Restrictions)
b. STS Equipment (Mooring lines, Fenders, Hoses)
c. Quantity of transferred cargo (STS operation duration)
6. Contingency Plan

STS documentation

According to IMO resolution MEPC 186(59) and the recommendations of INTERTANCO and OCIMF, records of the undertaken STS operations should be maintained. This documentation should be incorporated, or at least be compatible with the ISM and SMS of the ship.

a. Checklist for Equipment testing and verification.
a. Notification of Coastal state. (SOPEP Annex 2)
b. Procedures prior the STS operation
c. Procedures during the STS operation
d. Procedures after the STS operation
e. Evaluation of the STS operation
a. STS Assessment checklist
b. Risk Assessment