This document describes a method to firstly identify the specific nature of oils spilled in the environment and secondly compare the chemical composition of spilled oil or oily samples with that of suspected sources. Specifically, the document describes the detailed analytical methods and data processing specifications for identifying the specific nature of oil spills and establishing their correlation to suspected sources. Even when samples or data from suspected sources are not available for comparison, establishing the specific nature (e.g. refined petroleum, crude oil, waste oil, etc.) of the spilled oil may still help constrain the possible source(s) of the spilled oil.
This methodology is restricted to petroleum related products containing a significant proportion of hydrocarboncomponents with a boiling point above 150°C. Examples are: crude oils, higher boiling condensates, diesel oils, residual bunker or heavy fuel oils, lubricants, and mixtures of bilge and sludge samples, as well as distillate fuels and blends. While the specific analytical methods may not be appropriate for lower boiling oils (e.g. kerosenes, jet fuels, or gasoline), the general concepts described in this methodology, i.e. statistical comparison of weatheringresistant diagnostic ratios, may have applicability in spills involving lower boiling oils.
Paraffin as petroleum product (for candles, etc.) is outside the scope of this method, because too many compounds have been removed during the production process. Still the method can be used to analyse the type of product involved.