Provided is a nuclear radiation monitor which has a surface on which are located separate, visible indicia, such as LEDs or an LCD array, with the indicia being distributed around an imaginary closed loop, preferably of circular configuration. The monitor includes a radiation-sensitive apparatus, including a radiation sensor, and the apparatus is adapted to create a discharge every time a particle or pulse of radiation strikes the sensor window with sufficient intensity. The device incorporates electrical circuitry for causing sequential discharges to energize the visible indicia in a similar sequence, such that the indicia are perceived to be in motion around the loop, with a rotational speed substantially proportional to the frequency of occurrence of the discharges. Included on the surface is a central area depicting an atom with at least 3 indicia, such as LEDs or an LCD array, which flash when a preset threshold is exceeded by the radiation rate. Also included in the unit is an audible alarm that cycles in sympathy with the flashing indicia.