Following a mandate from the European Commission, the European Food Safety Authority has developed a Guidance on Technical Requirements (Guidance on Particle-TR), setting out information requirements for applications in the regulated food and feed product areas, and establishing criteria for assessing the presence of a fraction of small particles. These requirements apply to particles requiring specific assessment at the nanoscale in conventional materials that do not meet the definition of engineered nanomaterial as set out in the Novel Food Regulation (EU) 2015/2283. The guidance outlines appraisal criteria grouped in three sections, to confirm whether or not the conventional risk assessment should be complemented with nanospecific considerations.. The first group addresses solubility and dissolution rate as key physicochemical properties to assess whether consumers will be exposed to particles. The second group establishes the information requirements for assessing whether the conventional material contains a fraction or consists of small particles, and its characterisation. The third group describes the information to be presented for existing safety studies to demonstrate that the fraction of small particles, including particles at the nanoscale, has been properly evaluated. In addition, in order to guide the appraisal of existing safety studies, recommendations for fulfilling the data gaps while minimising the need for conducting new animal studies are provided. This Guidance on Particle-TR complements the Guidance on Nanoscience and Nanotechnology adopted by the EFSA Scientific Committee in 2018. Applicants are advised to consult both guidance documents before conducting new studies.