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2023 Proficiency Test (PT) on Fuel Oil started


The letter of instructions can be downloaded here as a pdf document. To download a document, please click the right mouse button and choose the "save as" option.


Please download the instructions for the PT iis23F03 here: the letter of instructions and the report form here

Download the instuctions for iis23F03M here: letter of instructions for Metalsand the report form here

Download the instuctions for iis23F03Br here: letter of instructions for Bromine No. & P-valueand the report form here

Download the instuctions for iis23F03C here: letter of instructions for Compatibilityand the report form here


Summary of this proficiency test:


On 22 November 2023 the proficiency test on Fuel Oil started with 145 participants from 62 different countries. On that date, the samples were dispatched to the laboratories. Enclosed to the sample is the material safety data sheet (MSDS).

Please confirm sample receipt as soon as you have received and checked the contents of the sample package via Please enter the date of receipt and press the "save date" button.


The samples can be analyzed on: Acid Number, API Gravity, Ash Content, Asphaltenes, Calculated Carbon Aromaticity Index, Carbon Residue, Density at 15°C, Flash Point PMcc, Heat of Combustion, Kinematic viscosity at 50°C/100°C, Viscosity Stabinger at 50°C/ 100°C, Nitrogen content, Pour Point, Sediment by extraction, Total sediment, Total Sulfur Content, Water by distillation, Water and Sediment, Distillation performed at 10 mm Hg, CHN-Analysis, Metals, Bromine Number, P-value (SMS1600), P-ratio (D7060), P-value (D7112), Separability Number (D7061) and Compatibility Rating. 


The deadline for reporting results is set on 29 December 2023. A laboratory that reports test results after the deadline will definitely not get direct feedback in case any of its results are suspect! So be in good time to get the most out of this proficiency test.

The test results should be reported via our internet based results reporting platform A login and a password can be requested via email to





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