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2023 Proficiency Test (PT) on Crude 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 iis23R01 here: the letter of instructions and the report form here

Download the instuctions for iis23R01Hg here: letter of instructions for Hg and the report form here


Summary of this proficiency test:


On 18 October 2023 the proficiency test on Crude Oil started with 159 participants from 69 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: TAN, API Gravity, BSW, Density at 15°C, Viscosity at 40°C, Light ends, Molecular Mass average, Pour Point, Salt, Sediment, Total Sulfur, Water, Total Mercury and Simulated Distillation. 


The deadline for reporting results is set on 24 November 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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