|Proficiency Test on Gasoline
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 11 January 2012, the proficiency test on Gasoline cfr EN228 specification (iis11B05EN) was finished. It started on 5 October 2011 (see message “Proficiency Test on Gasoline started” on this website) when the samples were distributed.
In this interlaboratory study 111 participants in 51 different countries have participated.
The participants were requested to determine API Gravity, Aromatics by FIA, Aromatics by GC, (%V/V and %M/M), Appearance, Benzene, Copper Strip Corrosion, Doctor Test, Density @ 15°C, Distillation (automated and manual), Existent gum, Lead, Manganese, Olefins by FIA, Olefins by GC (%V/V and %M/M), DIPE, Ethanol, ETBE, MTBE, Iso-Butanol, TAME, t-Butanol, Ethers >C5, Methanol, Oxygen, Oxidation Stability, Sulphur, RON and MON (before and after correction), Air Saturated Vapour Pressure (ASVP) and Dry Vapour Pressure Equivalent (DVPE).
The proficiency test report summarises per test, the test results, the analytical methods reported by the participants and the z-scores calculated 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. EN, ISO, ASTM...).