Click here to go back to the previous page


2023 Proficiency Test (PT) on Vacuum Gasoil 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 iis23G08 here: the letter of instructions and the report form here

Download the instuctions for iis23G08M here: letter of instructions for M and the report form here


Summary of this proficiency test:


On 8 November 2023 the proficiency test on Vacuum Gasoil started with 57 participants from 26 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, Aniline Point, Asphaltenes, Carbon Residue, Density at 15°C, Flash Point PMcc, Kinematic viscosity at 50°C, Kinematic viscosity at 100°C, Nitrogen, Pour Point, Total Sulfur, Al, Si, As, Ca, Cu, Fe, Ni, Na, V, Simulated distillation and Distillation performed at 10 mmHg. 


The deadline for reporting results is set on 15 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





©1996-2023 Institute for Interlaboratory Studies