Check if your olfactometer is compliant with the new EN 13725. Your accreditation is at risk.

historyTOSeries   As many of you already know, the EN 13725 was published in February 2022. There are many new provisions in the new text that needs to be reviewed in detail, but maybe one of the most impacting in the day-to-day operations of the over 400 laboratories around the world is the one of the minimal recovery rate accepted for olfactometers.

   With the new standard in hand, no olfactometer can be used for odour measurement under the EN 13725 accreditation scheme, unless recovery rates of 70 % or higher has been tested for four test gases: hydrogen sulphide, n-butanol, propanoic acid and dimethyl sulphide. That means that any olfactometer in the world needs to pass this test if an accreditation is needed. And this is no cheap test.

   In fact, the standard mentions that the parts of the olfactometer in contact with the gas should have stainless steel with the technical properties to avoid inadequate recovery (e.g. passivated stainless steel), in particular of H2S and reduced sulphur compounds.

   That is, if your olfactometer is older than, let's say, a 3-4 years, you should probably bring the stainless steel pieces of your device for a coating or plating if you want to make sure that you have a sufficient recovery rate of all the test gases mentioned by the new standard.

   Then either you or the maker of your olfactometer should test with an adequate technique, such as Proton Transfer Reaction Mass Spectrometry (PTR-MS), the recovery rate of these gases. As mentioned before, this is no cheap task, and it is not affordable for everyone.

   That means that hand-made devices or old olfactometers will need to get either tested, or replaced by new ones if a lab wants them to be used under the EN 13725 accreditation scheme.

   Unfortunately if you kept one of those old TO series olfactometers from the eighties that you see on the picture above, you will probably need to replace them ;-)


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Carlos Nietzsche Diaz Jimenez's Avatar

Carlos Nietzsche Diaz Jimenez

Carlos is the editor-chief of and has been in the odour world since 2001. Since then, Carlos has attended over 90 conferences in odour management, both national and international and authored a few papers on the subject. He has also organized a few international meetings and courses. Carlos owns a small company named Ambiente et Odora (AEO). He spends his free time with his wife and his twins, Laura and Daniel, and of course, writing on

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