This standard describes design and performance requirements along with testing methods for evaluating radiation detection instruments that are pocket-sized and worn on the body for the purpose of rapid detection and identification of radioactive materials. The performance requirements contained in this standard are meant to provide a means for verifying the capability of these instruments to reliably detect changes above background levels of radiation, notify the user to these changes, and provide a means to determine if the alarm was caused by a radionuclide of interest that may require further evaluation. These devices are not primarily intended to provide a measurement of dose-equivalent rate. However, their indication can provide an approximate value of exposure rate that should be reasonably accurate. They are also not meant to provide radionuclide identification at the same level as radionuclide identification detectors defined in ANSI N42.34.1 Successful completion of the tests described in this standard should not be construed as an ability to identify all radionuclides in all environments.