The validation of the draft European CEN standard for dynamic olfactometry by an interlaboratory comparison on n-butanol

A draft European odour standard has been prepared by the CEN working group CEN/TC264/WG2 'Odours'. As a final step in the preparation of the standard a validation of its quality criteria was required. To achieve this validation an Interlaboratory Comparison for Olfactometry (ICO) was organised with 19 laboratories from five European countries participating. The test substance was n-butanol in a concentration range from 15 to 400 ppm/v. From the qualified laboratories 36% fulfilled the criteria on both accuracy (< 0.217) and repeatability (< 0.477), calculated from the logarithms of test results expressed as threshold in ppb. This result was discussed in the working group and it was decided that the criteria were attainable. The draft CEN standard will be issued in November 1997 for public enquiry among the members of the CEN organisation followed by voting in 1998.