Click here to go back to the previous page


2023 Proficiency Test (PT) on Gasoil - ASTM (winter) 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 iis23G06 here: the letter of instructions

Download the instuctions for iis23G06CN here: letter of instructions for Cetane number and DCN

Download the instuctions for iis23G06TC here: letter of instructions for Total Contamination

Download the instuctions for iis23G06OX here: letter of instructions for Oxidation Stability


Summary of this proficiency test:


On 30 August 2023 the proficiency test on Gasoil - ASTM (winter) started with 172 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: API Gravity, Aromatics, Acid Number, Ash content, Cetane Index, Cloud Point, CFPP, Color, Carbon residue, Copper Corrosion at 50°C, Density at 15ºC, Distillation, FAME content, Flash Point PMcc, Kinematic viscosity at 40°C, Lubricity by HFRR, Nitrogen, Pour Point, Sulfur content, Water, Water and Sediment, Cetane Number & DCN, Particulate and Total Contamination and Oxidation Stability. 


The deadline for reporting results is set on 6 October 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