Why is ionizing radiation used

For example, beta particles in fallout can cause severe burns to the skin, known as beta burns. Radiosotopes that emit beta particles are present in fission products produced in nuclear reactors and nuclear explosions.

Some beta-emitting radioisotopes, such as iodine , are administered internally to patients to diagnose and treat disease. Gamma and x-ray radiation consists of packets of energy known as photons. Photons have no mass or charge, and they travel in straight lines. The visible light seen by our eyes is also made up of photons, but at lower energies. The energy of a gamma ray is typically greater than kiloelectron volts keV--"k" is the abbreviation for kilo , a prefix that multiplies a basic unit by 1, per photon, more than , times the energy of visible light 0.

If alpha particles are visualized as bowling balls and beta particles as golf balls, photons of gamma and x-radiation are like weightless bullets moving at the speed of light.

Photons are classified according to their origin. Gamma rays originate from events within an atomic nucleus; their energy and rate of production depend on the radioactive decay process of the radionuclide that is their source. X rays are photons that usually originate from energy transitions of the electrons of an atom.

These can be artificially generated by bombarding appropriate atoms with high-energy electrons, as in the classic x-ray tube. Because x rays are produced artificially by a stream of electrons, their rate of output and energy can be controlled by adjusting the energy and amount of the electrons themselves.

Both x rays and gamma rays can penetrate deeply into the human body. How deeply they penetrate depends on their energy; higher energy results in deeper penetration into the body. A 1 MeV "M" is the abbreviation for mega , a prefix that multiplies a basic unit by 1,, gamma ray, with an energy 2,, times that of visible light, can pass completely through the body, creating tens of thousands of ions as it does.

Climate Change. Climate Feedback. Ocean Acidification. Rising Sea Level. Ionizing radiation is radiation that can strip electrons from atoms. This process is shown above. May 20, Physics for Scientists and Engineers , 3rd ed. May 19, Ionizing Radiation [Online]. As shown in the aturally-occurring U decay series, the final product of the decay series is lead Pb , which is stable. Of note in this series is radon Rn , a radioactive gas that poses an inhalation hazard to workers and the public see the Hazard Recognition page.

Source: U. Geological Survey. Uranium decay series naturally-occurring , which produces alpha, beta, and gamma radiation not shown. Radioactivity is the number of energized particles or photons emitted by a source of radioactive material per unit of time.

Another way to describe radioactivity is the number of decays also described as disintegrations occurring per unit of time. Units of measurement for radioactivity are the Curie Ci, traditional U. What Happens to the Radiation Emitted? Ionizing radiation particles e. As shown in the graphic and table below, while alpha and beta particles are not very penetrating through other materials, gamma and X-rays are quite penetrating, as are neutrons.

The illustration shows the penetrating power of different types of ionizing radiation, ranging from the least penetrating alpha particles to the most penetrating neutrons. When ionizing radiation interacts with humans, it is capable of damaging living cells in the human body.

Humans can be exposed: 1 to external radiation from a radiation source outside of the body, such as an X-ray from an X-ray machine; or 2 through internal exposure following inhalation breathing in , ingestion swallowing , or wound uptake i.

In addition, the skin can become contaminated with radioactive materials when proper controls are not in place to prevent contamination or following an emergency. More information about the health effects of ionizing radiation is provided on the Health Effects page. Units of measurement for radiation exposure are the Roentgen R, traditional U. The Hazard Recognition page provides information about external exposure and internal exposure. Absorbed dose is the amount of radiation energy absorbed per unit mass i.

Units of measurement for absorbed dose are the rad traditional U. Equivalent dose is the amount of radiation absorbed by an individual i. Units of measurement for equivalent dose are the rem traditional U. Relevant equivalencies include:. Effective dose is the dose to the whole body that carries with it the same risk as a higher dose to a portion of the body. The effective dose is the sum of the tissue-weighted equivalent doses. For example, suppose the lungs received an equivalent dose of 8 rem 0.

Using the weighting factor of 0. Therefore, in this example, an equivalent dose of 8 rem 0. Skip directly to site content Skip directly to page options Skip directly to A-Z link.

Radiation and Your Health. Section Navigation. Facebook Twitter LinkedIn Syndicate. The Electromagnetic Spectrum: Ionizing Radiation. Minus Related Pages. On This Page. What is ionizing radiation? How much ionizing radiation am I exposed to? What is the risk from exposure to ionizing radiation? More information. We are exposed to low levels of ionizing radiation every day. Ionizing radiation can fall into two categories: natural and manmade Ionizing Radiation from Natural Sources Ionizing radiation that comes from natural sources is typically at low levels.

For more information on possible health effects from radiation and radiation dose, click here These low levels of exposure vary with location, altitude and type of building materials used in home construction.

In nature, sources of ionizing radiation include: Radiation from space cosmic and solar radiation Radiation from the earth terrestrial radiation Radon Radiation from building materials Ionizing Radiation from Manmade Sources Every day, we use Ionizing radiation to help us live healthy lives. Natural Sources Natural sources of ionizing radiation usually release ionizing radiation at low levels, which also means the amounts of radiation absorbed by our bodies doses is usually small.

For more information on radon, click here Manmade Sources Medical diagnostic exams are the main manmade source of ionizing radiation exposure in the U.