4. Ionizing radiation

We can speak of radiation when there is an energy transfer through indirect (electromagnetic radiation with a wave character) or direct (particle radiation) contact. If this radiation issufficiently energetic to remove an electron from the outer shell of an atom, this atom gets positively charged and an ion is created. Examples of

  • indirect ionizing radiation: gamma-rays (wavelength <0,01 nm), X-rays (wavelength about 0.01 to 100 nm) and ultraviolet light (wave length about 100 to 400 nm)
  • direct ionizing radiation: alpha radiation, beta radiation (distinguishable between electrons and positrons), neutrons and protons.

The ionizing radiation can be both of artificial (radioactive substances in hospitals such as iodine, technetium, cobalt, iridium, cesium,...or electrical equipment such as X-ray machines and cyclotrons) or natural (radioactive substances in the nature such as uranium and its decay products thorium, radium and radon or cosmic radiation as natural beta and gamma radiation) origin. Some occupationally exposed groups include workers of nuclear power stations, in the industrial quality assurance, radiological and certain medical andscientific personnel and airline cabin crew. The health effects can be probability-bound (stochastic such as cancer) or non-probability bound (deterministic such as skin burns,haematopoietic and gastrointestinal disorders and teratogenic effects for pregnant women).



  • CEN/TR 14715:2004 Safety of machinery - Ionizing radiation emitted by machinery - Guidance for the application of technical standards in the design of machinery in order to comply with legislative requirements
  • NBN EN 421:2010 Protective gloves against ionizing radiation and radioactive contamination
  • NBN EN ISO 11137:2006 (-1 to -3) Sterilization of health care products - Radiation
  • NBN EN 60325:2005 Radiation protection instrumentation - Alpha, beta and alpha/beta (beta energy > 60 keV) contamination meters and monitors
  • NBN EN 60846:2006 Radiation protection instrumentation - Ambient and/or directional dose equivalent (rate) meters and/or monitors for beta, X and gamma radiation
  • NBN EN 61005:2006 Radiation protection instrumentation - Neutron ambient dose equivalent (rate) meters
  • NBN EN 61331(-1 to -3):1999 to 2002, Protective devices against diagnostic medical X-radiation
  • NBN EN 61526:2007 Radiation protection instrumentation - Measurement of personal dose equivalents Hp(10) and Hp(0,07) for X, gamma, neutron and beta radiations - Direct reading personal dose equivalent meters and monitors
  • NBN EN 62022:2007 Installed monitors for the control and detection of gamma radiations contained in recyclable or non-recyclable materials transported by vehicles
  • NBN EN 62387:2012 Radiation protection instrumentation - Passive integrating dosimetry systems for environmental and personal monitoring
  • more information on http://www.nbn.be/