1. Dosimeter Radiation Detector: FNIRSI GC01 Geiger counter nuclear radiation detector with builtin GM sensor, fast response time and high accuracy, can detect gamma, beta and Xrays. Cumulative equivalent dose: 0.00uSv 500.0mSv Energy range: 48KeV 1.5MeV ≤ ± 30% (for 137Cs) 2. Intelligent alarm: Select the alarm setting option to set the current dose alarm value and cumulative dose alarm value. Regardless of whether the screen of the portable dosimeter is at rest or in operation, the radiation monitor automatically sounds an alarm when the detected radiation dose exceeds the alarm limit. Light/vibration/sound. There are 3 combined alarm modes to choose from. 3. Multifunctional Geiger Counter Our Geiger counter has various settings, such as alarm setting, system clock setting, unit setting and voice switching. You can work in English (default) or Chinese. Easy onehanded operation. 4. Working Principle: This nuclear radiation tester is used to determine the intensity of ionizing radiation (beta particles, gamma rays and Xrays). FNIRSI GC01 uses a Geiger Miller counter. A gas pipe or a small chamber is used as a probe. When the voltage applied to the probe reaches a certain range, each time the radiation in the tube is ionized to create an ion pair, it can be amplified to produce an electrical pulse of the same size.