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2023 Proficiency Test (PT) on Base 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 iis23L03 here: the letter of instructions and the report form here


Summary of this proficiency test:


On 19 April 2023 the proficiency test on Base Oil started with 63 participants from 34 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: Total Acid Number, Air-release time at 50°C, Color ASTM, Conradson Carbon Residue, Density at 15°C, Evaporation loss by Noack test, Flash Point C.O.C., Kinematic viscosity at 40°C/100°C, Viscosity Index, Viscosity Stabinger at 40°C/ 100°C, Pour Point Manual/ Automated, Rust Prevention, Sulfur, Water content by KF and Water Separability at 54°C.   


The deadline for reporting results is set on 26 May 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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