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01.07.2019 - Cosmetics

Preservative Efficacy Test for Cosmetics – Consideration of Measurement Uncertainties

Like all results of microbiological testing, those of the preservative efficacy test are subject to a certain analytical measurement uncertainty. This should be considered when interpreting the results of a preservative efficacy test.

For example, in DIN EN ISO 11930, a deviation of up to 0.5 log levels is not defined as a deviation. One of the few interlaboratory comparisons carried out on this topic dates back to 2012. In addition to the BAV Institute, a number of other laboratories participated in this study.

It was found that the results are always subject to measurement uncertainty. This can be reduced through appropriate standardization, such as test strains, media, etc. However, it will always remain and must be considered when interpreting the results.

Further information on this ring test can be retrieved at www.goech.at.

Do you have questions about the measurement uncertainty of the PET or other microbiological methods? Contact us, we will be happy to help you and provide support in interpreting the results.