Beta radiation can penetrate human skin to the "germinal layer," where new skin cells are produced. If high levels of 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 and a thin-window GM probe e. Some beta emitters, however, produce very low-energy, poorly penetrating radiation that may be difficult or impossible to detect.
Examples of these difficult-to-detect beta emitters are hydrogen-3 tritium , carbon, and sulfur Clothing provides some protection against beta radiation.
Examples of some pure beta emitters: strontium, carbon, tritium, and sulfur Gamma and X Radiation Gamma radiation and x rays are highly penetrating electromagnetic radiation. Some characteristics of these radiations are: Gamma radiation or x rays are able to travel many feet in air and many inches in human tissue.
They readily penetrate most materials and are sometimes called "penetrating" radiation. X rays are like gamma rays. X rays, too, are penetrating radiation. Sealed radioactive sources and machines that emit gamma radiation and x rays respectively constitute mainly an external hazard to humans. X-ray imaging creates pictures of the inside of your body. The images show the parts of your body in different shades of black and white. This is because different tissues absorb different amounts of radiation.
Calcium in bones absorbs x-rays the most, so bones look white. Fat and other soft tissues absorb less and look gray. Air absorbs the least, so lungs look black. The most familiar use of x-rays is checking for fractures broken bones , but x-rays are also used in other ways. For example, chest x-rays can spot pneumonia. Mammograms use x-rays to look for breast cancer. Click here for more information on radiation therapy for cancer.
When used appropriately, the diagnostic benefits of x-ray scans significantly outweigh the risks. X-ray scans can diagnose possibly life-threatening conditions such as blocked blood vessels, bone cancer, and infections. However, x-rays produce ionizing radiation—a form of radiation that has the potential to harm living tissue. This is a risk that increases with the number of exposures added up over the life of the individual.
However, the risk of developing cancer from radiation exposure is generally small. In general, if imaging of the abdomen and pelvis is needed, doctors prefer to use exams that do not use radiation, such as MRI or ultrasound. However, if neither of those can provide the answers needed, or there is an emergency or other time constraint, an x-ray may be an acceptable alternative imaging option.
Children are more sensitive to ionizing radiation and have a longer life expectancy and, thus, a higher relative risk for developing cancer than adults. Parents may want to ask the technologist or doctor if their machine settings have been adjusted for children. Click on the following links for information about risks for specific procedures:. CT computed tomography.
Current research of x-ray technology focuses on ways to reduce radiation dose, improve image resolution, and enhance contrast materials and methods. For detailed examples of research advancements for specific imaging procedures, click on the links below:.
How do medical x-rays work? When are medical x-rays used?
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