What is radiation?
All matters are made up of tiny units called atoms. As radiation is mainly released from atoms, the first step to understand radiation is to know more about their structure and properties:
Radiation is everywhere in the universe. Since the inception of time, lives on earth have been exposed to radiation in the natural environment.
Radiation embraces electromagnetic waves (such as light, radiowaves, x-rays, etc.), ultrasound and particles (such as alpha (a) particles, beta (b) particles, etc.) emitted by radioactive materials as they decay.
Radiation can be classified as non-ionizing and ionizing. In general, the energy of the non-ionizing radiation (such as light and radiowaves) is low and not sufficient to change the chemical properties of a substance. On the other hand, ionizing radiation (such as a and b particles) has energy high enough to remove electrons from an atom to create an electrically charged ion. This ionization process often results in chemical changes in living tissues, which can lead to injury in the organism. Ionizing radiation is generally referred as harmful radiation.
Radiation cannot be heard, seen, smelt nor tasted. Most of it cannot be felt. However, with the use of instruments, it can be detected and measured.