- Squat of the ship due to Shallow water effect and the necessity to Reduce Speed to decrease its effect
- The vessels Heeling (due to Wind or Turning) and Pitching movement
- Reliability of Charted Depth Data
- Predicted Tidal Levels including if any expected Negative Surge
- Areas of Mobile Bottom (Silting / Sand-waves)
- Any change in Water Density in passage (and its effect on draft)
- Accuracy of Actual Draft
- Reduced depths over Pipelines and other Obstructions
In the rare instance when a vessel is required to enter the port with UKC of less than 10%, the Master is to notify the managing office prior transit. He should also do so if he is in any doubt that sufficient clearance can be maintained throughout the voyage.
Special UKC policy for VLCC & Deep Draught vessels Transiting through Malacca straits & Singapore straits (Shall be complied in addition to above):
