IEC 62755:2012+A1:2020 provides a uniform format for data to be output from radiation measurement instruments for use in detection of illicit trafficking of radioactive materials. This enables interpretation of data without reference to manufacturer's documentation. This standard specifies the data format used for both required and optional data available at the output of radiation measurement instruments that are used for the detection of illicit trafficking of radioactive materials. The performance requirements for these types of radiation measurement instruments are described in other standards such as IEC 62401, IEC 62533, IEC 62694, IEC 62244, IEC 62327, IEC 62484, and IEC 62618. THIS CONSOLIDATED VERSION CONSISTS OF THE FIRST EDITION (2012) AND ITS AMENDMENT 1 (2020). THEREFORE, NO NEED TO ORDER AMENDMENT IN ADDITION TO THIS PUBLICATION.