What is radiation? How to reduce exposure Radiation is the release of energy from the unstable People are exposed to radiation every day from natural nucleus of an atom that travels in waves or particles. and human-made sources. The federal government The effect of radiation is defined by its ability to works to reduce radiation doses by regulating the ionize — or remove electrons from atoms. Ionizing production, use, and disposal of hazardous materials. radiation produces charged ions that can pass through matter, unlike non-ionizing radiation which is Too much exposure to uncontrolled radiation can be commonly produced by everyday electronic devices. harmful, so experts use time, distance, and shielding to help protect themselves. Time means limiting the amount of time spent near a source of radiation. Distance means increasing the physical space between Electron a source of radiation and other objects. Shielding Negative charge that surrounds an e means using a material that protects other objects atom’s nucleus from ionizing radiation, as shown below. & YOU Neutron Neutral charge Ionizing Radiation Radiation p n found inside an atom’s nucleus is energy Proton Alpha Positive charge in motion! found inside an atom’s nucleus Beta

Gamma Where does radiation Neutron come From? Ionizing radiation is released from an atom as either Paper Aluminum Thick Lead Concrete an alpha particle, beta particle, neutron particle, or Stops Alpha Stops Beta Stops Gamma Stops Neutron gamma ray. Alpha radiation is created when an atom’s Particles Particles and X-Rays Particles nucleus releases two protons and two neutrons as a single particle. Beta radiation is created when a To reduce neutron changes to a proton in the atom’s nucleus. REDUCE Increase USE Radiation Exposure: Time Distance Shielding Neutron radiation is created when an uranium or plutonium atom fissions, producing nuclear energy. Gamma radiation is a ray or wave of energy that is similar to the wavelength of X-rays.

   08/2021 www.energy.gov/lm/programs/stem-lm

Naturally Occurring Radiation Human-Made Radiation Uses for nuclear technology Most radiation on Earth comes from natural sources Though radiation mostly occurs naturally, half of a Radiation supports life by advancing medicine, found in the air, water, and soil. The human body typical person’s daily dose of radiation comes from research, and technology. contains some natural radioactive minerals, such as artificial sources. Both natural and human-made potassium-40. Over time, this radioactive material radiation can be detected using special instruments. accumulates in our bodies, primarily through eating and drinking. INDUSTRIAL AND SPACE EXPLORATION MEDICAL Radiation is used in a The Sun The highest exposure variety of ways — from Cosmic radiation to human-made capturing harmful particles radiation comes from in power station emissions Cosmic radiation is medical procedures, to manufacturing nonstick when high-energy like computerized cookware. Radiation helps particles travel tomography (CT) space exploration by powering through space to scans or X-rays. spacecraft and satellites. Earth. People living at higher elevations tend to be exposed Humans to higher rates of Internal radiation Sterilization and sanitation cosmic radiation. Humans give Radiation is used to disinfect medical supplies, off radiation like surgical tools, and kill harmful bacteria and just like cosmic or germs. Food irradiation is a radiation-based terrestrial sources. method used to destroy microorganisms, improve food safety, and extend shelf life.

Rocks & Soils Building Materials Education Terrestrial radiation Some building materials contain Teachers and scientists use naturally occurring radioactive radioactive materials to conduct Uranium and thorium elements, that decay into radon gas. research. For example, carbon dating are sources of terrestrial Older homes and buildings are often can determine the age of mummies, radioactive material, found in tested for radon to protect human fossils, and other artifacts. the rocks and soils on Earth. health and the environment. Tobacco Products Energy 92 Nuclear power plants use U Tobacco products contain fission — the process of Uranium radioactive isotopes. splitting the nucleus of atoms 238.028 Smokers receive a higher — to produce heat that turns annual radiation dose. turbines and generators, which produces electricity for homes and businesses.