Electromagnetic radiation (or "extreme") ultraviolet. UV, with X-ray and gamma radiation, are referred to as ionizing radiation due to the ability of photons of this radiation to produce ions and free radicals in materials (including living tissue). Since such radiation can severely damage life at energy levels that produce little heating, it is considered far more dangerous (in terms of damage-produced per unit of energy, or power) than the rest of the electromagnetic spectrum. The heat ray is an application of EMR that makes use of microwave frequencies to create an unpleasant heating effect in the upper layer of the skin. A
All About Radiation who has made a special study of radiation and its effects. He said that Hubbard's knowledge of radiation, as displayed by his writings in "All About Radiation", was the 'sort of knowledge that perhaps a boy who has read Intermediate Physics might, with a lot of misapprehensions and lack of understanding, demonstrate'... From this witness's evidence it is apparent that Hubbard is completely incompetent to deal with the subject of radiation and that his knowledge of nuclear physics is distorted, inaccurate, mistaken and negligible. No evidence was called which disputed in any way these conclusions." All About Radiation All About