Measurement of Ionizing Radiation

Radiation detection differs totally from the analysis of chemical molecules and biology. Generally, ionizing radiation is the result of radioactivity of matter and is emitted by a radioactive atomic nucleus in consequence of a nuclear decay or other particular nuclear reactions. Furthermore, ionizing radiation can be produced in man-made nuclear accelerators and reactors. Humans do not have any sense organs to detect ionizing radiation – we cannot see, taste, smell, hear, or feel it. Certainly this is a main reason why radioactivity and ionizing radiation is often regarded with skepticism by the general public, at least in most Western countries. Although ionizing radiation has been present in nature (naturally occurring radioactive materials and cosmic radiation) throughout man's history, it remained unnoticed until less than 120 years ago, when W.C. Röntgen discovered X-ray radiation (1895) and A.H. Becquerel (1896) discovered the radioactivity of matter. These discoveries initiated the development of the first coarse radiation meters. Especially, the nuclear weapons program, starting in the 1940s, later the civil nuclear power industry, and last but not least the safeguard efforts of the International Atomic Energy Agency (IAEA) boosted the development of a wide variety of radiation detectors and radioactivity measuring systems for many different kinds of measuring tasks in the different nuclear and radiological scenarios.