What is radiation?

Radiation is a form of energy. Radiation comes from man-made sources such as x-ray machines, from the sun and outer space, and from some radioactive materials, such as uranium in soil. Small quantities of radioactive materials occur naturally in the air we breathe, the water we drink, the food we eat, and even in our own bodies. Radiation that goes inside our bodies causes what we refer to as internal exposure. External exposure is from radiation from sources outside our body, such as radiation from sunlight and man-made and naturally occurring radioactive materials. Radiation doses that people receive are measured in units called roentgen equivalent in man (rem) or sievert. One sievert is equal to 100 rem. Scientists estimate that the average person in the United States receives a dose of about 1/3 of a rem per year. Eighty percent of typical human exposure comes from natural sources and 20% comes from artificial radiation sources, primarily medical X-rays

Visit the following page to learn how radiation exposure can be reduced through time, distance and shielding: Radiation Exposure Protection

Radiation affects the body in different ways, but the adverse health consequences of exposure may not be seen for many years. Adverse health effects range from mild effects, such as skin reddening, to serious effect such as cancer and death. These adverse health effects are determined by the amount of radiation absorbed by the body (the dose), the type of radiation, the route of exposure, and the length of time a person is exposed.

Acute radiation syndrome (ARS), or radiation sickness, is usually caused when a person receives a high dose of radiation to much of the body in a matter of minutes. Survivors of the Hiroshima and Nagasaki atomic bombs and firefighters responding to the Chernobyl nuclear power plant event in 1986 experienced ARS. The immediate symptoms of ARS are nausea, vomiting, and diarrhea. Later, bone marrow depletion may lead to weight loss, loss of appetite, feeling like you have the flu, infection, and bleeding. The survival rate depends on the radiation dose. For those who do survive, full recovery takes from a few weeks to 2 years.

Children exposed to radiation may be more at risk than adults. Radiation exposure to the unborn child is of special concern because the human embryo or fetus is extremely sensitive to radiation.

Radiation exposure, like exposure to the sun, is cumulative. Radiation can affect the body in a number of ways, and the adverse health consequences of exposure may not be seen for many years. These adverse health effects can range from mild effects, such as skin reddening, to serious effects such as cancer and death, depending on the amount of radiation absorbed by the body (the dose), the type of radiation, the route of exposure, and the length of time a person is exposed. Exposure to very large doses of radiation may cause death within a few days or months. Exposure to lower doses of radiation may lead to an increased risk of developing cancer or other adverse health effects.

Radiation cannot be detected by human senses. A variety of instruments are available for detecting and measuring radiation.

Radiation can affect the body in a number of ways, and the adverse health effects of exposure may not be apparent for many years. These adverse health effects can range from mild effects, such as skin reddening, to serious effects, such as cancer and death, depending on the amount of radiation absorbed by the body (the dose), the type of radiation, the route of exposure, and the length of time a person was exposed.

After a release of radioactive materials, local authorities will monitor the levels of radiation and determine what protective actions to take. The most appropriate action will depend on the situation. Tune to the local emergency response network or news station for information and instructions during any emergency. For more information, visit the following page: Radiation Exposure Protection

People who are externally contaminated with radioactive material can contaminate other people or surfaces that they touch. For example, people who have radioactive dust on their clothing may spread the radioactive dust when they sit in chairs or hug other people. People who are internally contaminated can expose people near them to radiation from the radioactive material inside their bodies. The body fluids (blood, sweat, urine) of an internally contaminated person can contain radioactive materials. Coming in contact with these body fluids can result in contamination and/or exposure.

There are specific treatments to speed the removal of radioactive materials within the body as well as reduce the effects of radiation exposure based on the specific radiological contamination type.

Small quantities of radioactive materials occur naturally in the air we breathe, the water we drink, the food we eat, and in our own bodies. Radiation that goes inside our bodies causes what we refer to as internal exposure. The exposure that is referred to as external comes from sources outside the body, such as radiation from sunlight and man-made and naturally occurring radioactive materials.

Radiation doses that people receive are measured in units called roentgen equivalent in man (rem) or sievert. One sievert is equal to100 rem. Scientists estimate that the average person in the United States receives a dose of about 1/3 of a rem per year. Eighty percent of typical human exposure comes from natural sources and the remaining 20 percent comes from artificial radiation sources, primarily medical x-rays.

Eighty percent of typical human exposure comes from natural sources and 20 percent comes from artificial radiation sources, primarily medical X-rays. Small quantities of radioactive materials occur naturally in the air we breathe, the water we drink, the food we eat, and even in our own bodies.

Radiation is used for medical and industrial purposes ranging from x-rays to decontaminating food.

Radiation exposure, like exposure to the sun, is cumulative. Radiation affects the body in different ways, but the adverse health consequences of exposure may not be seen for many years.Adverse health effects range from mild effects, such as skin reddening, to serious effect such as cancer and death. These adverse health effects are determined by the amount of radiation absorbed by the body (the dose), the type of radiation, the route of exposure, and the length of time a person is exposed. Children exposed to radiation may be more at risk than adults. Radiation exposure to the unborn child is of special concern because the human embryo or fetus is extremely sensitive to radiation.

Acute radiation syndrome (ARS), or radiation sickness, is usually caused when a person receives a high dose of radiation to much of the body in a matter of minutes. Survivors of the Hiroshima and Nagasaki atomic bombs and firefighters responding to the Chernobyl nuclear power plant event in 1986 experienced ARS. The immediate symptoms of ARS are nausea, vomiting, and diarrhea; later, bone marrow depletion may lead to weight loss, loss of appetite, feeling like you have the flu, infection, and bleeding. The survival rate depends on the radiation dose. For those who do survive, full recovery takes from a few weeks to 2 years.

At the end of World War II, the United States detonated 2 nuclear devices over Hiroshima and Nagasaki, Japan. In the ensuing years, above- and below-ground nuclear weapons testing was conducted by several nations. There have also been significant radiological accidents at the nuclear power plants in Three Mile Island, Pennsylvania, and Chernobyl, Ukraine.

More information can be obtained from the US Government sources on this page: Radiation Information