Examples of Radiation

Understanding What Radiation Is (and Is not)

This is the symbol for radioactivity. Radioactive materials emit radiation, but so do many non-radioactive objects.
This is the symbol for radioactivity. Radioactive materials emit radiation, but so do many non-radioactive objects. Yagi Studio, Getty Images

Radiation is the emission and propagation of energy. A substance does not need to be radioactive in order to emit radiation because radiation encompasses all forms of energy, not just those produced by radioactive decay. However, all radioactive materials do emit radiation.

Radiation Examples

Here are some examples of different types of radiation:

  1. ultraviolet light from the sun
  2. heat from a stove burner
  1. visible light from a candle
  2. x-rays from an x-ray machine
  3. alpha particles emitted from the radioactive decay of uranium
  4. sound waves from your stereo
  5. microwaves from a microwave oven
  6. electromagnetic radiation from your cell phone
  7. ultraviolet light from a black light
  8. beta particle radiation from a sample of strontium-90
  9. gamma radiation from a supernova
  10. microwave radiation from your wifi router
  11. radio waves
  12. a laser beam

As you can see, most of the examples on this list are examples from the electromagnetic spectrum, but the energy source doesn't need to be light or magnetism to qualify as radiation. Sound, after all, is a different form of energy. Alpha particles are moving, energetic helium nuclei (particles).

Examples of Things That Are Not Radiation

It's important to realize isotopes are not always radioactive. For example deuterium is an isotope of hydrogen that is not radioactive. A glass of heavy water at room temperature does not emit radiation.

(A warm glass of heavy water emits radiation as heat.)

A more technical example has to do with the definition of radiation. An energy source may be capable of emitting radiation, but if the energy doesn't propagate outward, it's not radiating. Take, for example, a magnetic field. If you hook up a coil of wire to a battery and form an electromagnet, the magnetic field it generates (actually an electromagnetic field) is a form a radiation.

However, the magnetic field surrounding the Earth is not typically considered radiation because it's not "detached" or propagating outward off into space.