Nanomaterials: Which methods are suitable for particle size determination?

Physical-chemical testing is based on the requirements of Annex VII of REACH Regulation (EC) No 1907/2006. In the context of further testing requirements, it is important to know whether your chemicals meet the criteria for "nano or not nano".

The OECD has published the new Test Guideline No. 125: "Nanomaterial Particle Size and Size Distribution of Nanomaterials" on 30.06.2022. In addition, the European Commission has developed a new recommendation for the definition of nanomaterials.

The OECD Test Guideline No. 125 lists seven methods for determining the particle size and size distribution of nearly spherical nanoparticles. Not every method is suitable for every material and for every application. Especially for SMEs it is often difficult to select and correctly apply the appropriate test methods or procedures. For registration under the REACH Regulation, it is necessary to reliably identify, classify and label nanoparticles in your products. The selection of unsuitable measurement methods may lead to a wrongly characterised product, whereby the obligations to fulfil the requirements of e.g. REACH are incorrectly fulfilled. Our digital information day is therefore intended to provide you with basic knowledge about the possibilities and limitations of the methods and to convey and facilitate the correct choice of method.