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2021 Proficiency Test (PT) on Engine Oil (fresh) 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 iis21L07 here: the letter of instructions and the report form here


Summary of this proficiency test:


On 12 May 2021 the proficiency test on Engine Oil (fresh) started with 76 participants from 43 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, Base Number, Color, Conrad Carbon Residue, Ramsbottom Carbon Residue, Carbon Residue, Density at 15°C, Evaporation loss by Noack, Flash Point COC and PMcc, Foaming Tendency & Foam Stability, Kinematic Viscosity at 40°C /at 100°C, Viscosity Stabinger at 40°C /at 100°C , Viscosity Index, Viscosity HTHS, Nitrogen, Pour Point, Sulfated ash, Sulfur, Water, Ca, P and Zn. 


The deadline for reporting results is set on 18 June 2021. 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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