Polimaster's PM1604A and PM1604B models are miniature energy-compensated personal dosimeters that measure personal dose equivalent Hp(10) and personal dose equivalent rate Hp(10) of both gamma and X-ray radiation. Recommended for use by professionals who work with or around the radioactive materials. The PM1604A and PM1604B perform the following functions: * Monitoring and measurement of the ambient dose equivalent and ambient dose equivalent rate across wide energy range: from the natural background level up to 5-10 Sv/h (500-1000 R/h); * Alerting the user through an audible alarm when the preset dose and/or dose rate thresholds are exceeded; * Recording and storing data for up to 1000 events in their non-volatile memory; * Transmitting all recorded data via an infrared channel to a PC for further processing and analysis.