Radioactivity and Radiation refers to the energy release resulting from the decay of specific atomic nuclei and isotopes.
Within atoms, nuclei, composed of protons and neutrons, are located at the center.
Radioactive nuclei are inherently unstable and undergo decay by emitting energetic particles, such as photons, electrons, neutrinos, protons, neutrons, or alpha particles (comprising two protons and two neutrons).
Some of these emitted particles are considered ionizing, possessing enough energy to displace electrons from atoms or molecules.
The level of radioactivity hinges on the proportion of unstable nuclei and the frequency of their decay.
The impact of radioactivity is contingent on the type and energy of particles generated during nuclear decay.
For instance, neutrinos continuously traverse the Earth, whereas alpha particles can be stopped by a simple sheet of paper.
Radioactivity and Radiation can inflict harm on materials and living organisms, including plants, animals, and human tissue.
Scientists and engineers harness radioactivity as a source of heat for applications like satellites, medical imaging, targeted cancer treatments, radiometric dating, and for investigating the fundamental laws of nature and the origins of matter.
What is Radioactive Contamination?
Contamination occurs when radioactive material is deposited on skin, clothing, or any place where is it not desired.
It is important to remember that radiation does not spread or get “on” or “in” people; rather it is radioactive contamination that can spread.
A person contaminated with radioactive materials will be irradiated until the source of radiation (the radioactive material) is removed.
Someone who is externally contaminated if radioactive element is on skin or clothing.
One who is internally contaminated if radioactive material is breathed in, swallowed, or absorbed through wounds.
The environment is contaminated if radioactive material is spread about or uncontained.
These electromagnetic radiations differ only in the amount of energy they have. Gamma rays and X-rays are the most energetic of these.
Gamma radiation is able to travel many meters in air and many centimeters in human tissue. It readily penetrates most materials.
X-rays are like gamma rays. They can also travel over long distances in both air and human tissue.
Radioactive materials that emit gamma radiation and X-rays constitute both an external and internal hazard to human.
Gamma radiation is detected with survey instruments, including civil defense instruments. Low levels can be measured with a standard Geiger counter.
Gamma radiation or X-rays frequently accompany the emission of alpha and beta radiation.
Instruments designed solely for alpha detection will not detect gamma radiation.
Pocket chamber (pencil) dosimeters, film badges, thermoluminescent, and other types of dosimeters can be used to measure accumulated exposure to gamma radiation.
Alpha radiation
Radiation is energy, in the form of particles or electromagnetic rays, released from radioactive atoms. The three most common types of radiation are alpha particles, beta particles, and gamma rays.
Alpha radiation is not able to penetrate skin.
Alpha-emitting materials can be harmful to humans if the materials are inhaled, swallowed, or absorbed through open wounds.
A variety of instruments have been designed to measure alpha radiation. Special training in use of these instruments is essential for making accurate measurements.
Instruments cannot detect alpha radiation through even a thin layer of water, blood, dust, paper, or other material, because alpha radiation is minimally penetrating.
Alpha radiation travels a very short distance through air.
Alpha radiation is not able to penetrate turnout gear, clothing, or a cover on a probe. Turnout gear and clothing can keep alpha emitters off of the skin. Personal protective equipment should be worn to protect clothing and otherwise uncovered skin from contamination of all types.
Beta radiation
Beta- radiation may travel meters in air and is moderately penetrating.
Also Beta radiation can penetrate human skin to the innermost layer of the epidermis where new skin cells are produced. If beta-emitting contaminants are allowed to remain on the skin for a prolonged period of time, they may cause skin injury.
Beta-emitting contaminants may be harmful if deposited internally.
Most beta emitters can be detected with a survey instrument. Some beta emitters, however, produce very low energy, poorly penetrating radiation that may be difficult or impossible to detect. Examples of these are carbon-14, tritium, and sulfur – 35.
Clothing and turnout gear provide some protection against most beta radiation.Personal protective equipment should be worn to protect clothing and otherwise uncovered skin from contamination of all types.
Gamma radiation
Gamma radiation and X-rays are electromagnetic radiation like visible light, radio waves, and ultraviolet light. These electromagnetic radiations differ only in the amount of energy they have. Gamma rays and X-rays are the most energetic of these.
Gamma radiation is able to travel many meters in air and many centimeters in human tissue. It readily penetrates most materials.
X-rays are like gamma rays. They can also travel over long distances in both air and human tissue.
Radioactivity and Radiation materials that emit gamma radiation and X-rays constitute both an external and internal hazard to humans.
Dense materials are needed for shielding from gamma radiation. Clothing and turnout gear provide little shielding from penetrating radiation but will prevent contamination of the skin by radioactive materials.
Gamma radiation is detected with survey instruments, including civil defense instruments. Low levels can be measured with a standard Geiger counter.
Gamma radiation or X-rays frequently accompany the emission of alpha and beta radiation.
Instruments designed solely for alpha detection will not detect gamma radiation.
Pocket chamber (pencil) dosimeters, film badges, thermoluminescent, and other types of dosimeters can be used to measure accumulated exposure to gamma radiation.
Importance of Radioactivity and Radiation
Radioactivity and Radiation is important for several reasons:
Scientific Understanding: Radioactivity was pivotal in understanding the structure of atoms and the nucleus. It led to the development of nuclear physics and the discovery of fundamental particles like protons, neutrons, and electrons.
Medical Applications: Radioactive isotopes are used in medicine for diagnostic imaging (e.g., PET scans) and cancer treatment (e.g., radiation therapy).
Energy Production: Nuclear power plants utilize controlled nuclear reactions to generate electricity, providing a significant source of low-carbon energy.
Dating Techniques: Radioactive isotopes like carbon-14 are used in radiometric dating to determine the age of archaeological and geological samples.
Industrial Uses: Radioactive sources are used for industrial purposes such as measuring material thickness, detecting flaws in structures, and sterilizing medical equipment.
Space Exploration: Radioactive power sources, like radioisotope thermoelectric generators (RTGs), provide reliable power for space probes and rovers in locations where solar power isn’t feasible.
Natural Processes: Understanding radioactivity is essential for studying natural processes like the Earth’s mantle convection, which is driven by heat produced from radioactive decay.
However, it’s important to manage and handle radioactive materials carefully due to their potential hazards to human health and the environment.
