Nuclear radiation dose alarm built-in high sensitivity Geiger technology tube as a detector, mainly used for monitoring all kinds of radioactive workplace X, y and hard beta radiation, with fast response, wide measurement range. It can display the current dose rate and accumulated dose rate of the workplace, and when the battery is replaced, the calendar, time and accumulated data can be saved permanently. Widely used in nuclear power plants, gas pedals, steel, chemical industry, isotope application, industrial X-y, radioactive stone, radiological medical treatment, cobalt source treatment, y radiation, iodine 131, radiological laboratories, environmental monitoring around the nuclear facilities and other fields of workers for personal safety protection monitoring and radioactivity alert.