Tanker operation : Preparation for discharge




Oil tanker at sea


Preparation of the Cargo Plan

• The Chief Officer shall prepare a detailed cargo oil discharge plan prior to arrival discharge port. The discharge plan shall be posted in the CCR at a conspicuous location, and distributed to all personnel directly involved in the discharge operation.
The discharge plan should be signed to confirm that personnel have read and fully understood the plan.




• The Chief Officer shall also prepare a watch schedule and Person in-Charge list for oil transfer operations for the discharge operation.

• Prior to commencement of discharge operation the Chief Officer shall conduct a “Pre transfer cargo safety meeting” with all the concerned crew and shall have a duty officer read aloud such discharge plan to all the attending officers and crew.
Special details, port requirements and special precautions or procedures should be discussed with all personnel involved in the discharge operation.

Preparation for Cargo Equipment

Cargo oil transfer pumps and IGS should be well prepared for use prior to arrival at discharge port terminal.

Cargo Oil Transfer Check Lists

The Chief officer shall complete the following check lists prior to, during and upon completion of cargo oil transfer operations.
The Chief Officer, after confirmation, shall affix his signature on the related checklist. The Master, shall then sign on the completed “Tanker Discharging Checklist”.

If there is to be a multi-port discharge, the pre-arrival tests, as listed herein, can be completed before the arrival at the first port.
• “Crude Oil Washing Checklist” .
• “Ship / Shore Safety Checklist”
• “Double Hull Operation/COT (Cargo Oil Tank) Monitoring Record”
• “Ship to Ship Transfer Checklist” , as required.

Display of Warning Notices and Signs
Should be taken into account

Hose Connection

The chief Officer or deck duty officer must be in attendance during connection of cargo oil transfer arms/hoses.

Cargo Oil Transfer Meetings with Terminal representative

The Master, Chief Engineer and Chief Officer must attend and carry out a “pre-transfer cargo safety meeting” with the shore facility representative to ensure full agreement with the cargo oil discharge plan, and to agree on method of communication during emergencies.

The “Ship/Shore Safety Check List” or relevant “Ship to Ship Transfer Check List” must be completed and signed for in agreement by both parties after successful completion of safety checks and confirmation and prior to starting of operations.

Ullage measurement and Cargo Quantity Calculation

Ullage and Temperature measurement, Water measurement, and Sampling are carried out by the terminal side or surveyors.

Normally, one watch Officer shall attend the measurement and assist to calculate the cargo quantity. Ensure that all ullage ports (vapor locks) and other openings have been Closed after the measurement and prior to start of operations.

Lining up Pipelines and Valves

Prepare the lines between tanks and pumps after the completion of ullage measurement. Tanks not to be discharged are to be suitably marked and protected from accidental miss-operation. Carry out the filling of the separator with utmost caution, taking care to avoid ”Liquid Hammer”. Ensure through passage of vapor so as to fill separator evenly.

Prior to commencing discharge the cargo tank line and pump room valves to be set as per the plan for start of discharge. Use the ship specific ‘Valve Checklist” prudently.

Valves not in use should be secured and lashed shut.

Line / Valve settings are to be supervised and checked by the Watch-Officer and re-confirmed by the Chief Mate.

The order for opening of manifold valve shall be under the chief officer’s permission. On opening of the manifold valves, the manifold pressure shall be monitored regularly. Operate major valves as per the terminal representative’s order.



Personnel arrangement at beginning of operations


In principle, for the start up of operations, all deck crew shall be in attendance and distributed as per chief officer’s instruction.

Onboard announcement

Have the crew know the beginning of operations to call their attention to smoking, use of fire, designated passage and other matters.



Related articles:

Pumproom entry precation Learn basic procedure for pumproom management




Other Info Pages
Home Our home page
Site Map Page listing for this site.
Site Use and Privacy - Read our privacy policy and site use information.
Contact us

Copyright © 2009 Ships business.com All rights reserved.








Crude oil washing for tankers

General guidances for tank cleaning

General precautions for ballasting procedure

Tanker operation in a laden voyage

General precautions for oil cargo discharging

Personnel arragement for oil tankers