EZ type radioactive calibration standards

EZ type standards are standards with a radioactive substance in a layer of paint evenly spread on a large duralumin plate. The paint layer has a surface density of less than 1 mg/cm2, the surface activity of surfaces larger than 15 cm2 does not differ from average surface activity by more than 10%. EZ standards serve to control the efficiency and stability of instruments for measuring contaminated surfaces and persons by α, β, γ sources of different energy. The manufacturer UVVVR Prague provides a warranty for the given values of surface activity and total standard error. (M.D.)