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Download the report (iis08L01unused-X) on the Unused Lubricating Oil

Download the report (iis08L01used-X) on the Used Lubricating Oil

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Summary of this proficiency test:

On 30 June 2008, the report on the Used Lubricating Oil (samples #0835 and #0836) was finished and on 16 July 2008, the report on the Unused Lubricating Oil (sample #0834). The proficiency test started on 9 April 2008 (see message “Proficiency Test on Lubricating Oil started” on this website) when the samples were distributed.

In this international interlaboratory study 92 participants in 48 different countries have participated.

The participants were requested to perform the following tests: Total Base Number, Total Acid Number, Colour, CRC, Density @15°C, Flash Point COC and PMcc, Kinematic Viscosity @40°C and @100°C, Nitrogen, Sulfur, Sulphated Ash, Pour Point and Water and 16 elements (wear metals and additives: Ag, Al, Ba, Ca, Cr, Cu, Fe, Li, Mg, Mn, Na, Ni, P, Pb, Sn, Si, Ti, V and Zn).  

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.