|Proficiency Test on Benzene and Toluene finished
The full report can be downloaded (as .pdf-file). To download the report, please click the right mouse button and choose the "save as" option.
Summary of this proficiency test:
On 15 June 2010, the proficiency test on Benzene and Toluene (iis10C04) was finished. It started on 7 April 2010 (see message “Proficiency Test on Benzene and Toluene started” on this website) when the samples were distributed.
In this international interlaboratory study 43 participants in 18 different countries have participated on Benzene.
In this international interlaboratory study 37 participants in 20 different countries have participated on Toluene.
The participants were requested to determine for Benzene : Acid wash color, Acidity, Appearance, Bromine index, Colour, Density @ 20 oC, Distillation, Total Chlorine, Total Nitrogen, Solidification point, Methylcyclohexane, Toluene, Nonaromatics and Purity. The participants were requested to determine for Toluene :Acid wash color, Appearance, Colour, Density @ 20 oC, Distillation, Purity, Copper Corrosion, Non aromatics hydrocarbons, Benzene and Styrene.
The proficiency test report summarises per test, the test results, the analytical methods reported by the participants and the z-scores calculated by i.i.s. for each participant are tabulated. Also, for each test, the calculated summary (e.g. mean, standard deviation and reproducibility) is given.
In the report also an evaluation of the test results is given. Problems encountered in the analyses are mentioned and - where possible - suggestions for quality improvement are formulated. For each test a comparison is made between the results of the group of participants and the requirements given by the relevant standard (e.g. ISO, DIN, ASTM).
Interested parties can order a hard copy of the report; the price for non-participants is Euro 35.