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ISO 18363 specifies a procedure for the simultaneous determination of 2-MCPD esters (bound 2-MCPD), 3‐MCPD esters (bound 3‐MCPD) and glycidyl esters (bound glycidol) in a single assay, based on acid catalysed ester cleavage and derivatization of cleaved (free) analytes with phenylboronic acid (PBA) prior to GC/MS analysis. ISO 18363-3 is applicable to solid and liquid fats and oils. For all three analytes the limit of quantification (LOQ) is 0,1 mg/kg and the limit of detection (LOD) is 0,03 mg/kg.

This document specifies a method to identify and compare the compositional characteristics of oil samples. Specifically, it describes the detailed analytical and data processing methods for identifying the characteristics of spill samples and establishing their correlation to suspected source oils. 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 still helps to constrain the possible source(s). This methodology is restricted to petroleum related products containing a significant proportion of hydrocarbon-components 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 are perhaps not appropriate for lower boiling oils (e.g. kerosene, jet fuel, or gasoline), the general concepts described in this methodology, i.e. statistical comparison of weathering-resistant diagnostic ratios, are applicable in spills involving these kinds of oils. Paraffin based products (e.g. waxes, etc.) are outside the scope of this method because too many compounds are removed during the production process [37]. However, the method can be used to identify the type of product involved. Although not directly intended for identifying oil recovered from groundwater, vegetation, wildlife/tissues, soil, or sediment matrices, they are not precluded. However, caution is needed as extractable compounds can be present in these matrices that alter and/or contribute additional compounds compared to the source sample. If unrecognized, the contribution from the matrix can lead to false “non-matches”. It is therefore advisable to analyse background sample(s) of the matrix that appear unoiled. When analysing “non-oil” matrices additional sample preparation (e.g. clean-up) is often required prior to analysis and the extent to which the matrix affects the correlation achieved is to be considered. Whether the method is applicable for a specific matrix depends upon the oil concentration compared to the “matrix concentration”. In matrices containing high concentrations of oil, a positive match can still be concluded. In matrices containing lower concentrations of oil, a false “non-match” or an “inconclusive match” can result from matrix effects. Evaluation of possible matrix effects is beyond the scope of this document.

This document specifies a test method for the determination of the oxidation stability of fuels for diesel engines at 110 °C, by means of measuring the induction period of the fuel up to 48 h. The method is applicable to fatty acid methyl esters (FAME) intended for the use as pure biofuel or as a blending component for diesel fuels, and to blends of FAME with diesel fuel containing 2 % (V/V) of FAME at minimum. The precision of the test method has been developed for conventional diesel. This test method is applicable for paraffinic diesel fuels as specified in EN 15940, however a separate precision statement for paraffinic diesel is not available. NOTE 1 EN 14112 [1] describes a similar test method for the determination of the oxidation stability of pure fatty acid methyl esters (see the Introduction to this document). Additionally, EN 16568 [3] describes a similar test method for the determination of the oxidation stability of fuels for diesel engines at 120 °C, by means of measuring the induction period of the fuel up to 20 h. This method is applicable to blends of FAME with diesel fuel containing 2 % (V/V) of FAME at minimum. Other alternative test methods for the determination of the oxidation stability of distillate fuels are described in CEN/TR 17225 [4]. NOTE 2 For induction periods higher than 48 h the precision is not covered by the precision statement of this method. The limit values of the relevant fuel standards are well within the scope of this test method. NOTE 3 The presence of cetane improver can reduce the oxidation stability determined by this test method. Limited studies with EHN (2-ethyl hexyl nitrate) indicated, however, that the stability is reduced to an extent which is within the reproducibility of the test method. NOTE 4 For the purposes of this document, the term "% (V/V)" is used to represent the volume fraction (φ) of a material.