There are still no commonly agreed definitions of the terms “nanotechnologies” and “nanomaterials”. The European Commission has suggested a definition of nanomaterials in 2011:
"'Nanomaterial’ means a natural, incidental or manufactured material containing particles, in an unbound state or as an aggregate or as an agglomerate and where, for 50 % or more of the particles in the number size distribution, one or more external dimensions is in the size range 1 nm-100 nm"
The OECD made also a suggestion for a definition (definition of the OECD Working Party on Manufactured Nanomaterials).
- European Commission 2011: Commission Recommendation of 18 October 2011 on the definition of nanomaterial (Official Journal of the European Union, 2011/696/EU)
- ISO/TS Norm 80004-1:2015 (fee-based)