The objective of the RENAAME project (Release of Nano-objects, their Aggregates and Agglomerates (NOAA) from Masks), supported for 3 years by ANSES and coordinated by LNE in partnership with INRS and SCIENSANO (Belgian public laboratory) is to develop a recognized and validated testing methodology for identifying the presence of nanomaterials declared or involved in the manufacture of masks and for evaluating the release of nanoparticles in the aerosol phase. This communication details the results of the first phase of the project, which aims to develop and validate a “screening” method for identifying the presence of Ti and Ag elements in masks.