The table below demonstrates the electromagnetic spectrum.
|Type of wave||Typical source||Example of detector||Approximate wavelength||Typical users||Dangers of over exposure|
|Radio: LW, MW and VHF||electronic circuits||aerial||1km, 100m and 1m||communications, radio, TV||safe (unless very concentrated)|
|Microwaves||electronic circuits||aerial||1cm||communications satellites, telephony, heating water and food||burning, if concentrated|
|Infra red (IR)||electronic devices, warm objects, sun||electronic detectors, heat-sensitive papers, black-bulb thermometer||0.1mm||detector in security lighting, remote controls (e.g. TV)||burning, if concentrated|
|Light; Red, Orange, Yellow, Green, Blue, Indigo, Violet||electronic devices (eg LED), sun||eye, photographic film, electronic components (eg LDR)||0.001mm||seeing, photography, communication (eg in optical fibres), laser surgery||burning, blindness if concentrated|
|Ultraviolet (UV)||sun, gas discharge, lamps||causes fluorescence (glowing) in some objects, film||0.00001mm||sun-tan lamp, making ions, making vitamin D, killing bacteria in water treatment plants||sunburn, skin cancer, retinal damage|
|X-rays||very fast electrons hitting a metal target||photographic film||imaging breaks/defects in bones, hidden devices||cell destruction, cell mutation, cancer|
|Gamma rays ( )||radioactive nuclei decaying||photographic film, GM tube||medical tracers, killing cancerous cells, sterilisation of surgical equipment||cell destruction, cell mutation, cancer|
The electromagnetic spectrum ranges from long wavelength, low frequency waves (like radio waves which can be used for communication) to short wavelength, high frequency waves (like gamma rays which can be used for medical treatment).
In the electromagnetic spectrum, waves with higher frequency have greater energy than lower frequency waves.