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2024 Proficiency Test (PT) on Benzene 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 iis24C01 here: the letter of instructions and the report form here


Summary of this proficiency test:


On 14 February 2024 the proficiency test on Benzene started with 50 participants from 25 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 wash color, Acidity, Appearance, Bromine Index, Color, Density at 20°C, Distillation, Purity, Nitrogen, Methylcyclohexane, Toluene, Nonaromatics, 1.4-Dioxane, Total Impurities, Solidification Point, Sulfur, Thiophene Water, Total Chlorides and Organic Chlorides. 


The deadline for reporting results is set on 22 March 2024. 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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