Oil and Regulations

The simple term of "oil" the oil pollution regulations, suggests that the regulations are precise. Actually, they are not, because the term oil lacks specificity.

In the oil pollution regulations, discharge of treated bilge water from machinery spaces is authorized, as long as the effluent quality is better than 5 or 15ppm oil content limit. That suggests something pretty specific, but is it?

Let us first look at "oil", what are we talking about? On a ship we are talking of fuel oil, lube oil, hydraulic oil, etc.

• In fuel oil we have a wide range of hydrocarbon chains, as it is generally a blend of residual with various cutter stocks;
• Lube oil is a complex blend of hydrocarbons plus detergents and additives, required for the job;
• And on goes the list with synthetic oils, bio oils, etc

All this to say that oil is not something defined, it is a summary expression for a range of hydrocarbon chains, meaning from the light fractions all the way to the heavy fractions in the refining process, singularly or in combination.

The absence of specificity on the term oil is not really the problem, the problem comes when attempting applying scientific limits to the determination of the oil content.

To be continued...