3.10 CLARIFICATION OF CHARTERER'S INSTRUCTIONS

The master is responsible for properly and carefully loading, handling, stowing, carrying, keeping, caring for and discharging the cargo. He and the chief officer must carefully study the cargo orders received and ensure that their cargo care procedures do not depart from the letter or intent of those instructions. If there is any doubt that the proposed loading meets the requirements of the cargo orders, then clarification must be requested.
The exchange of information during the pre-loading conference may disclose a discrepancy between the loading orders held by the vessel and the intentions of the shore terminal. If the instructions of the loading terminal fall outside the quantity, quality, or specification indications of the charterer's loading orders, loading must be deferred until the difference can be resolved.
The master should immediately advise owners of the difference, indicating the contents and date of the latest orders received by the vessel, and the contents and date of the latest instructions to the shore terminal. This inquiry should be copied to the charterers. The vessel must then wait until confirmation by charterer's before loading.
Charterer's sometimes require the slops to be spread evenly around the vessel's tanks before loading. See section 2.19 for recommendations for responding to such a request, or similar requests to depart from the standard load-on-top procedures.
If the cargo is to consist of two or more 'parcels' of different crude oils and LOT procedures are followed, then the largest parcel should be loaded on top of any retained slops.

3.10.1 Blending (or 'spiking') on board
Cargo orders will occasionally call for the cargo to be loaded in parts at one or more berths and blended on board. This can be done, provided:
- The loading plan is prepared which provides acceptable stress, trim and transverse and damage stability at all times.
- The heavier cargo is loaded first.
- Cargo vapour pressure will at all times be within the capability of the tank and venting systems.
- No guarantee is offered by the vessel owner or managers of a homogeneous cargo outturn.

3.10.2 Commingling
When a vessel receives advice that two grades of cargo may be commingled, either on loading or at discharge, the master must request confirmation in writing from the charterer/shipper/receiver before accepting or discharging the cargo on a commingled basis.