Beta radiation — is a flow of electrons or positrons, which results from beta nuclei decay. Beta radiation has lower ionizing but higher penetrating power than that of alpha. Any shelter may serve a protection here. Beta particles can easily penetrate human skin and cause tissue damage and burns. X-rays and Gamma radiation — electromagnetic radiation, which comes together with nuclear transformations.
Gamma rays are photons that come from the nucleus of the atom. Both types of ionizing radiation can pass through the human body if they have enough energy. It appears extremely difficult to protect oneself from both X-rays and gamma-rays. Neutron radiation denotes a flow of neutrons, i. To protect oneself from this type or radiation one may use protective shelter, radiation protective covers, specially equipped basement or cellar.
For example, a carbon atom has six protons and eight neutrons, and is unstable i. To become more stable, the C atom releases radiation by turning a neutron into a proton and ejecting an electron i. Having gained a proton and lost a neutron, the radioactive C atom becomes stable nitrogen N , with seven protons and 7 neutrons. Fluorine F is an example of a positron-emitting radionuclide that is commonly used in medical facilities for positron emission tomography PET scanning.
An F atom has nine protons and nine neutrons, and is unstable i. To become more stable, the F atom releases radiation by turning a proton into a neutron and ejecting a positron. Having gained a neutron and lost a proton, the radioactive F atom becomes stable oxygen O , with eight protons and 10 neutrons. Neutral i. Neutrons are high-speed nuclear particles that are the only type of ionizing radiation that can make objects radioactive.
Nuclear fission and fusion reactions, as well as neutron sources e. For example, neutrons would be produced from the detonation of a fissile nuclear weapon, such as an improvised nuclear device IND.
High-energy electromagnetic photons emitted from the nucleus of an unstable, excited atom. Gamma rays are pure energy and can travel great distances at high speed. Gamma rays are often emitted along with alpha or beta particles during radioactive decay e. High-energy electromagnetic photons emitted from outside the nucleus. The primary difference between X-rays and gamma rays is that X-rays are emitted from processes outside the nucleus, but gamma rays originate inside the nucleus.
Radioactive decay is a process by which unstable i. The rate of radioactive decay for each radioactive element is described by its half-life, or the amount of time it takes for around half of the radioactive atoms present to decay to a more stable form. Half-lives for different radioactive elements vary from fractions of seconds to billions of years.
Unstable radioactive atoms can go through a series of decays, or disintegrations, before reaching a stable form. Th has a half-life of 24 days and decays by beta particle emission to protactiniumm Pam , which has a half-life of only 1. 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. For more information on non-ionizing radiation, click here. Ionizing radiation is a form of energy that acts by removing electrons from atoms and molecules of materials that include air, water, and living tissue.
Ionizing radiation can travel unseen and pass through these materials. It is on the right side of the electromagnetic spectrum in the figure below. For more information on the electromagnetic spectrum, click here. A familiar example of ionizing radiation is that of x-rays, which can penetrate our body and reveal pictures of our bones.
Ionizing activity can alter molecules within the cells of our body. That action may cause eventual harm such as cancer. Intense exposures to ionizing radiation may produce skin or tissue damage. For more information on x-rays and other forms of medical imaging, click here. Other examples of ionizing radiation include alpha, beta, and gamma rays from radioactive decay.
Ionizing radiation can fall into two categories: natural and manmade. Ionizing radiation that comes from natural sources is typically at low levels. This means that the usual amount of ionizing radiation from natural sources absorbed by our bodies dose is small. 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.
You may also be exposed to the radioactive gas radon if your house or building has a leaky foundation. Every day, we use Ionizing radiation to help us live healthy lives. Ionizing radiation is found in smoke detectors, used to disinfect medical instruments and blood, and to perform many other tasks in our daily lives.
It is also a byproduct of nuclear power generation. Our main exposure to ionizing radiation in manmade sources is through the use of diagnostic medical exams. Ionizing radiation can penetrate the human body and the radiation energy can be absorbed in tissue.
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