Data Review Meeting of the 6th Collaborative Materials Exercise (CMX-6) of the Nuclear Forensics International Technical Working Group (ITWG) was held in Warsaw on June 4-7, 2019. The meeting was organized by the Institute of Nuclear Chemistry and Technology at the request of the chairmen of the ITWG. The ITWG is a forum for collaboration among official nuclear forensics practitioners who share a common interest in preventing illicit trafficking of nuclear and radioactive materials. The group is formed by the institutions from 25 countries around the world as well as the JRC. The INCT joined the ITWG in 2018. The ITWG works to advance the best practices of nuclear forensics largely through participation in a series of collaborative materials exercises (CMX). The CMX-6 was conducted in the 2018/2019 year. 23 countries took part in the CMX-6 and 43 representatives participated in the meeting. The participants of CMX-6 were requested to analyse two pieces of radioactive metals found in a recycled waste and identify any linkages between them. The main purpose of the meeting was present, compare and discuss results obtained by the participants and exchange information on nuclear forensics with other laboratories. CMX-6 will result in furthering the development of two guidance documents.
