a portable, handheld, electronic instrument consisting of three components used to detect ionizing radiation

An instrument used to measure radiation, typically radiation exposure dose. The instrument usually consists of an energy compensated Geiger Müller tube and associated circuitry which causes a meter deflection or other readout in the presence of ionizing radiation.

An instrument used for detecting radioactive material or for measuring exposure. Different survey meters include: ZnS(Ag) Scintillator – measures alpha radiation contamination NaI Scintillator – measures gamma radiation exposure Ion Chamber – measures beta/ gamma radiation exposure Geiger-Muller Tube – measures alpha/ beta/ gamma radiation contamination and beta/ gamma radiation exposure Pressurized Ion Chamber - measures gamma radiation exposure

is any portable radiation detection instrument especially adapted for inspecting an area to establish the existence and amount of radioactive material present.