Click here to go back to the previous page


2021 Proficiency Test (PT) on Hydraulic 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 iis21L09 here: the letter of instructions


Summary of this proficiency test:


On 6 October the proficiency test on Hydraulic Oil (fresh) started with 39 participants from 30 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, Copper Strip 3hrs at 50°C, Density at 15°C, Flash Point PMcc, Foaming Characteristics, Kinematic viscosity at 40°C / 100°C, Viscosity Index, Viscosity Stabinger at 40°C / 100°C, Pour Point, Sulfur, Water, Water Separability, Ca, P and Zn. 


The deadline for reporting results is set on 12 November 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





©1996-2020 Institute for Interlaboratory Studies