The dilution method is a process by which replacement ballast water is filled through the top of the ballast
tank intended for the carriage of ballast water with the simultaneous discharge from the bottom at the same
flow rate and maintaining a constant level in the tank throughout the ballast exchange sequence. Pumping
through three times the volume of each ballast water tank is considered to meet the 95% volumetric exchange.
In some cases, pumping through less than three times the volume of the ballast tank may be acceptable,
provided the vessel can demonstrate that at least 95% volumetric exchange has been met.