645 - 07/09 - Risks associated with fuel switching - Worldwide


The Association would like to highlight the risks encountered when switching over between residual and distillate fuels to satisfy emission regulations.

As a larger number of areas bring in restrictions on emissions from merchant ships the practice of switching over from residual fuels like HFO to distillate fuels like MDO will become a more regular event. Following on from the introduction of emission restrictions in the state of California (Bulletin 638 - 5/09) the American Petroleum Institute (API) set up a marine engine technical issues working group to look at the hazards associated with switching between fuels.

The major concern is that the process of fuel switching could cause a lack of propulsion through a shut down of the main or auxiliary engines. The working group mentioned above, has compiled a report on the technical considerations when switching over fuel which can be accessed below.

Technical Considerations of Fuel Switching Practices

The report states that this shut down could occur from a number of technical reasons as well as a result of fuel incompatibility. Technical issues can be resolved onboard by following a proven procedure for switching between fuels. The issues relating to fuel compatibility are harder to control onboard but the industry is working towards regulating fuel quality and bunker handling through tighter controls.

The Association would advise that engine manufacturers are consulted, fuel selection is monitored, an in-depth fuel switching procedure is developed and utilised, maintain all related equipment to a high standard, conduct appropriate crew training and carry out all switching operations well offshore before entering restricted waters.

Additionally members should circulate the above report to engineers, superintendents, operators, technical managers and others who may benefit from its content.

Source of information:

United States Coastguard



Staff Author