Gamma rays are produced from radioactive decay, in nuclear reactions, and in fission. Gamma rays are dangerous because they have great penetrating ability. Several millimeters of lead are needed to stop g rays. Illustration used by permission of the Uranium Information Centre, Melbourne, Australia Radiation is measured in two units - rads and rems. It is significant because not all radiation has the same biological effect.
X rays have the same characteristics as gamma ways, but they are produced differently.
In 1895 Wilhelm Roentgen observed that when high-speed electrons hit metals, the electrons stopped and released an electromagnetic wave. He named this energy wave an x ray. Neutrons are released during the nuclear fission process and during certain nuclear reactions. Neutrons trigger the nuclear chain reaction. Neutrons do not carry an electrical charge.