Why changeover timing matters
Before a ship enters an Emission Control Area it must be burning fuel that meets the 0.10% sulphur limit, unless an approved scrubber is in use. The settling tank, service tank, heaters, purifiers and pipework still hold the previous grade. That volume has to be consumed or isolated before the ECA line. Starting too late leaves high-sulphur fuel in the line at the boundary.
How this calculator works
Flush time = Remaining system fuel ÷ Consumption rate. A safety margin is then added. If an ECA entry time is entered, the tool subtracts flush time plus margin to show when changeover should start. Remaining fuel should include tanks still lined up plus an estimate of pipe and heater volume from the company’s changeover plan. Viscosity and temperature must also be managed during the change.
Who should use it
Useful for the chief engineer planning an ECA approach. Record the actual start and finish times in the official changeover log. This page is a timing aid only.