Main Difference – Ionizing vs. Nonionizing Radiation
Radiation involves a transfer of energy through space. Depending on the amount of energy carried by radiation, radiation can be classified into ionizing radiation and nonionizing radiation. The main difference between ionizing and nonionizing radiation is that ionizing radiation refers to types of radiation where the radiation carries enough energy to ionize atoms, whereas nonionizing radiation refers to types of radiation that do not carry enough energy to ionize atoms.
What is Ionizing Radiation
Ionizing radiation refers to types of radiation that carry enough energy to cause ionizations in atoms. There is no strict agreed upon cutoff value for energy that we can use to discriminate between ionizing and nonionizing radiation types.
In terms of electromagnetic radiation, a type of radiation could be considered to be “ionizing” if the energy associated with a photon of that particular type of radiation has an energy which is comparable to, or larger than, typical ionizing energies of atoms. In the electromagnetic spectrum, higher-energy ultraviolet, X-rays and gamma rays are taken to be ionizing.
In terms of nuclear radiation, both alpha and beta particles have the ability to ionize. Of these, alpha particles have more ionizing power. However, alpha particles have a smaller range and their penetration ability is low. Other types of particles having large amounts of energies can also give enough energy to electrons and cause them to ionize. If living tissues are exposed to ionizing radiation, atoms making up DNA in cells could become ionized. This causes the DNA to malfunction and could lead to cancer.
Ionizing radiation is not all bad: we can make good uses of it as well. For instance, we use gamma rays to sterilize medical equipment. X-rays, of course, are vital for medical imaging. In these cases, the doses of ionizing radiation that people are exposed to are quite low, and so the chance that this radiation could cause cancer is very low. Ionizing radiation released by supernovae cause nebulae to produce glowing lights, giving us some of the most breathtaking astronomical images ever taken.
Ionizing radiation released by supernovae cause nebulae to glow.
What is Nonionizing Radiation
Nonionizing radiation refers to types of radiation that do not have enough energy to cause ionizations in atoms. In terms of electromagnetic radiation, photons of low-energy ultraviolet, visible light, infrared, microwaves and radio waves do not have enough energy to cause ionizations. Heat flow by thermal radiation typically involves an infrared electromagnetic wave, so it is nonionizing.
There is no direct evidence to prove that nonionizing radiation can cause cancer. However, the International Agency for Research on Cancer (IARC) has classified electromagnetic fields as possible contributors to cancer [1]. In the broad sense, includes nonionizing types of electromagnetic radiation as well, including microwaves (used in mobile phones) and radio and TV signals.
Difference Between Ionizing and Nonionizing Radiation
Energy for Ionization:
Ionizing radiation carries enough energy to cause ionizations in atoms.
Nonionizing radiation does not carry enough energy to cause ionizations.
Effects:
Ionizing radiation is known to have the ability top cause cancer.
Nonionizing radiation may cause cancer, but there is no direct evidence to support this.
References:
- International Agency for Research on Cancer. (2011, May 31). IARC CLASSIFIES RADIOFREQUENCY ELECTROMAGNETIC FIELDS AS POSSIBLY CARCINOGENIC TO HUMANS. Retrieved September 25, 2015, from IARC – INTERNATIONAL AGENCY FOR RESEARCH ON CANCER
Image Courtesy:
“In one of the most detailed astronomical images ever produced, NASA/ESA’s Hubble Space Telescope captured an unprecedented look at the Orion Nebula…” by NASA, ESA, M. Robberto (Space Telescope Science Institute/ESA) and the Hubble Space Telescope Orion Treasury Project Team [Public Domain], via Wikimedia Commons
