The International Organization for Standardization (ISO) has published a technical report that sets forth a methodology to classify and categorize nanomaterials.  

The report, ISO/TR 11360, describes a method of classifying nanomaterials according to their size, chemical nature, properties, and characteristics. According to the August 17, 2010, report, the approach will be used in forthcoming documents that will provide internationally agreed-to definitions of nanomaterials. The classification system, called the “nanotree,” places nanotechnology concepts into a logical context by depicting their relationships as a branched-out tree with the most basic elements defined as the main trunk.