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Frequent Questions about Radiation Protection

View frequently asked questions and answers related to radiation protection by topic.

On this page:

About EPA's Radiation Protection Program
Radiation in Medicine
Radiation Sources
Radioactive Waste
Radiological Events
Regulations, Guidance & Compliance

About EPA's Radiation Protection Program

What authorities does the EPA have to protect people from radiation?

How does the EPA protect people from radiation?

Where can I find EPA publications related to radiation protection?

What other organizations are involved with radiation protection in the U.S.?

Radiation in Medicine: General Information

What are the risks from radiation exposure from medical imaging?

How is radiation used to diagnose patients?

Is it safe for children or pregnant women to have a medical imaging procedure that uses radiation?

Radiation in Medicine: X-Rays

How much radiation am I exposed to when I get a medical x-ray procedure?

How can I minimize x-ray radiation exposure?

What are x-rays and how are they used in medicine?

Is it safe for me to get a medical x-ray?

Radiation in Medicine: CT/CAT Scans

How much radiation am I exposed to when I have a CT scan?

What is a CT/CAT scan and how is it used?

Is it safe for me to get a CT scan?

Where can I find more information about CT scans?

Radiation in Medicine: Fluoroscopy

How much radiation am I exposed to when I have a fluoroscopic procedure?

Is it safe for me to have a fluoroscopic procedure?

Where can I find more information about fluoroscopy?

What is interventional fluoroscopy and how it is used?

Radiation Sources: Consumer Products

Are imported products screened for radiation hazards?

Is labeling required for radiation-emitting consumer products?

Is there radioactivity in food?

What federal standards address radioactivity in food?

What is food irradiation?

Who monitors radioactivity in domestic and imported foods?

What kinds of consumer products contain radioactive materials?

Radiation Sources: Granite

What advice does the EPA have about radon for consumers who have granite countertops?

Can I test my granite countertops for radiation?

Are granite countertops radioactive? Are the levels dangerous?

Are there regulations about radiation in granite countertops?

Radiation Sources: Non-Ionizing Radiation

Where can I find information about living near a cell phone tower?

Where can I get information about electromagnetic radiation from smart meters?

Where can I get information about electric and magnetic fields from power lines?

Are there regulations concerning radiation emissions from power lines?

Radiation Sources: Cell Phones

Where can I find information about cell phone safety concerns?

Where can I get information about electromagnetic radiation from cell phones?

Radiation Sources: Nuclear Power Plants

Where can I get information about a specific nuclear power plant?

How is the EPA involved with the regulation and safety of nuclear power plants?

What does the EPA do if there is a nuclear power plant accident?

Radiation Sources: Naturally Occurring Radioactive Materials

What is radon gas? Is it dangerous?

Where does radon gas come from?

What is background radiation? Is background radiation a risk to me and my family?

Where can I find more information about radon in my home?

Radioactive Waste: General Information

What is the Orphan Sources Initiative?

Which radionuclides are found at Superfund sites?

How is mixed waste regulated?

What is the EPA's Radiation Site Cleanup Program?

What other agencies regulate nuclear waste?

What is high-level radioactive waste?

Who regulates waste from nuclear power plants?

What is Superfund?

Radioactive Waste: WIPP

Where is the transuranic waste that will be disposed at the WIPP stored now?

What is Transuranic Radioactive Waste?

Where can I get more information about the WIPP?

What is the recertification process for the Waste Isolation Pilot Plant? Where can I find more information about the recertification process?

How can the public get information of the EPA's WIPP activities?

What is the WIPP and how is the EPA involved?

Does the EPA consider the environmental and health issues of transporting radioactive waste to the WIPP in New Mexico?

Radioactive Waste: Yucca Mountain

What authority does EPA have to set standards that protect public health and the environment at Yucca Mountain?

What are the characteristics of Yucca Mountain?

Where does the proposed Yucca Mountain waste come from, and where is it currently stored?

Which federal agencies have a role at Yucca Mountain?

When will the Yucca Mountain repository be operational?

What is the Yucca Mountain repository?

What is the EPA's role in the Yucca Mountain project?

Radiological Emergency Response at the EPA

What kinds of experts and equipment does the EPA’s radiation protection program have to support a radiological emergency response effort?

What is the EPA's role during a radiological emergency?

Radiological Events: Emergency Preparedness

What should I do in case of a radiological emergency?

What can I do to prepare for a radiological emergency?

Will it be safe for me to eat food or drink water from my area after a radiological emergency?

Should I take Potassium Iodide (KI) during a radiological emergency?

Radiological Events: Protective Action Guides (PAGs)

What are the critical changes between the 1992 and 2017 version of the PAG Manual?

At what point and what concentrations will I be told to stop drinking tap water during a radiological emergency?

Where can I find trainings on using the 2017 PAG Manual?

Where can I obtain a copy of the EPA's Protective Action Guides Manual?

What is a drinking water PAG?

How does the drinking water PAG work with EPA’s existing Safe Drinking Water Act regulations?

How do officials know when it is time to carry out protective actions?

What are Protective Action Guides (PAGs) and why are they important?

How is the new PAG Manual being implemented in the FEMA Radiological Emergency Preparedness (REP) Program?

When do states need to implement the 2017 PAG Manual?

How do the PAGs inform safety measures during and after a radiological emergency?

Why is there a need for a drinking water PAG when the EPA already has regulations for radionuclides in drinking water?

Radiological Events: Fukushima

What is the EPA doing about tracking radiation in our environment from Fukushima?

Where can I find the most current information about Fukushima and radiation levels in the environment?

Where can I get information on seafood safety related to Fukushima?

Does EPA monitor the ocean for radiation from Fukushima?

Radiation Regulations, Guidance and Compliance: Compliance Software

How do I merge my population datasets from older versions of CAP-88 to CAP-88 Version 4?

Is CAP-88 PC appropriate for estimating exposures from short-term or "accidental" releases?

I’m having trouble with the CAP-88 software; who can I ask for help?

Where can I find information about demonstrating compliance with 40 CFR Part 61, Subpart H and I?

Can I use models other than COMPLY, CAP-88 and AIRDOS-PC to demonstrate compliance with Subpart H and Subpart I?

How should a facility demonstrate compliance for radionuclides not included in CAP88-PC?

Radiation Regulations, Guidance and Compliance: MARSSIM General Questions

How can I use MARSSIM?

Am I required to use MARSSIM?

How can I contact MARSSIM workgroup members?

Does MARSSIM conflict with existing guidance?

What is the Multi-Agency Radiation Survey and Site Investigation Manual, and who uses it?

What guidance does MARSSIM provide on specific phases and aspects of site surveys?

Radiation Regulations, Guidance and Compliance: MARSSIM Technical Questions

What is the relationship between survey unit size and the establishment of the DCGLW?

Why would I want to perform double sampling?

How is the MDC calculated?

What sizes does MARSSIM recommend for survey units?

What is a Derived Concentration Guideline Level (DCGL)?

What is the major consequence of missing an elevated area?

What is the Minimum Detectable Concentration (MDC)?

What is the relative shift?

When should I choose a value for the LBGR?

Does MARSSIM allow double sampling?

Can I use a different size survey unit than the example in MARSSIM?

What is the effect on the DCGLW when I decrease or increase the survey unit size?

What is the LBGR?

What value should I use for the LBGR, if there is no prior survey information?

How can I obtain DCGLs?

What is a scan MDC?

How do I choose the LBGR?

How does the DCGL affect the survey design?

Why do I need an LBGR?