Espa?ol
PDFs by language
Our 24/7 cancer helpline provides information and answers for people dealing with cancer. We can connect you with trained cancer information specialists who will answer questions about a cancer diagnosis and provide guidance and a compassionate ear.
Chat live online
Select the Live Chat button at the bottom of the page
Call us at 1-800-227-2345
Available any time of day or night
Our highly trained specialists are available 24/7 via phone and on weekdays can assist through online chat. We connect patients, caregivers, and family members with essential services and resources at every step of their cancer journey. Ask us how you can get involved and support the fight against cancer. Some of the topics we can assist with include:
For medical questions, we encourage you to review our information with your doctor.
We are all exposed to some amount of radiation just from being on this planet. You can, however, limit your exposure to some sources of radiation, such as x-rays from imaging tests, radiation in the workplace, and radon in your home.
We are all exposed to some amount of radiation just from being on this planet. You can, however, limit your exposure to some sources of radiation, such as x-rays from imaging tests, radiation in the workplace, and radon in your home.
The increased risk of cancer from exposure to any single imaging test is likely to be very small. But radiation exposure from all sources can add up over one’s lifetime, so imaging tests that use radiation should only be done if there is a good medical reason to do so. The usefulness of the test must always be balanced against the possible risks from exposure to the radiation.
Sometimes, other imaging tests that don’t use radiation such as ultrasound or MRI might be an option. But if there is a reason to believe that an x-ray or CT scan is the best way to look for cancer or other diseases, a person will most likely be helped more than the small dose of radiation can hurt.
If you do need a test that will expose you to some radiation, ask if there are ways to shield the parts of your body that aren’t being imaged from being exposed. For example, a lead apron can sometimes be used to protect parts of your chest or abdomen from getting radiation, and a lead collar (known as a thyroid shield or thyroid collar) can be used to protect your thyroid gland.
For more detailed information about radiation doses from imaging tests in adults, see Understanding Radiation Risk from Imaging Tests.
Exposure to radiation from imaging tests is of particular concern in children because their bodies are smaller and more sensitive to radiation. It’s important for parents to ask questions before the child has a test such as an x-ray or CT scan, to make sure that the test is really needed and, if it is, that the facility is experienced in adjusting radiation doses for children.
In the US, several federal agencies are charged with protecting workers from radiation exposure, including the Occupational Safety and Health Administration (OSHA), the Nuclear Regulatory Commission, and the Department of Energy. Each agency is responsible for a different set of workplaces, but all follow the same general principles. If you work someplace where radiation exposure is likely, your employer can tell you which agency sets the standards for your workplace.
In general, employers cannot allow employees to be exposed to levels of radiation over a certain (low) limit without telling them of the risks. They also must take steps to monitor the level of exposure and make sure that it stays below certain limits. Workers can do their part by learning about the risks and following safety procedures, which may include using protective clothing and equipment.
For most people, the largest potential source of radon exposure is in the home. You can check radon levels in your home, either with do-it-yourself kits or by hiring a professional. If the levels are high, there are steps you can take to lower them.
For more information, see Radon and Cancer.
The American Cancer Society medical and editorial content team
Our team is made up of doctors and oncology certified nurses with deep knowledge of cancer care as well as editors and translators with extensive experience in medical writing.
Environmental Protection Agency. Radiation Protection: Frequent Questions about Radiation Protection. 2022. Accessed at https://www.epa.gov/radiation/frequent-questions-about-radiation-protection on November 4, 2022.
National Cancer Institute. Radiation Risks and Pediatric Computed Tomography (CT): A Guide for Health Care Providers. 2018. Accessed at https://www.cancer.gov/about-cancer/causes-prevention/risk/radiation/pediatric-ct-scans on November 4, 2022.
Last Revised: November 10, 2022
American Cancer Society medical information is copyrighted material. For reprint requests, please see our Content Usage Policy.
Sign up to stay up-to-date with news, valuable information, and ways to get involved with the American Cancer Society.
If this was helpful, donate to help fund patient support services, research, and cancer content updates.