Radiation damage is the effect of ionizing radiation on physical objects including non-living structural materials. It can be either detrimental or beneficial for materials. Radiobiology is the study of the action of ionizing radiation on living things, including the health effects of radiation in humans. High doses of ionizing radiation can cause damage to living tissue such as radiation burning and harmful mutations such as causing cells to become cancerous, and can lead to health problems such as radiation poisoning. Causes This radiation may take several forms: Cosmic rays and subsequent energetic particles caused by their collision with the atmosphere and other materials. Radioactive daughter products (radioisotopes) caused by the collision of cosmic rays with the atmosphere and other materials, including living tissues. Energetic particle beams from a particle accelerator. Energetic particles or electro-magnetic radiation (X-rays) released from collisions of such particles with a target, as in an X ray machine or incidentally in the use of a particle accelerator. Particles or various types of rays released by radioactive decay of elements, which may be naturally occurring, created by accelerator collisions, or created in a nuclear reactor. They may be manufactured for therapeutic or industrial use or be released accidentally by nuclear accident, or released sententially by a dirty bomb, or released into the atmosphere, ground, or ocean incidental to the explosion of a nuclear weapon for warfare or nuclear testing. Effects on materials and devices Radiation may affect materials and devices in deleterious and beneficial ways: By causing the materials to become radioactive (mainly by neutron activation, or in presence of high-energy gamma radiation by photodisintegration). By nuclear transmutation of the elements within the material including, for example, the production of Hydrogen and Helium which can in turn alter the mechanical properties of the materials and cause swelling and embrittlement. By radiolysis (breaking chemical bonds) within the material, which can weaken it, cause it to swell, polymerize, promote corrosion, cause belittlements, promote cracking or otherwise change its desirable mechanical, optical, or electronic properties. On the other hand, radiolysis can also be used to induce crosslinking of polymers, which can harden them or make them more resistant to watering. By formation of reactive compounds, affecting other materials (e.g. ozone cracking by ozone formed by ionization of air). By ionization, causing electrical breakdown, particularly in semiconductors employed in electronic equipment, with subsequent currents introducing operation errors or even permanently damaging the