Research involving exposure of humans to ionizing radiation requires additional specific approval from the University Radiation Safety Committee (HIRE subcommittee) or Radioactive Drug Research Committee (RDRC). The following guidance is provided to help you determine which committee approval is required for your study.

  • If your study does not involve exposure to radiation, (e.g. CT scans, X-rays, administration of radiopharmaceuticals) beyond standard of care, you do not need to include a radiation risk statement in the consent form. Standard of care means that the patient would receive the scan, X-ray, etc. even if they did not participate in the study.

  • If your study involves a single X-ray procedure that is listed below under "Uses of Ionizing Radiation That Do Not Need to Be Reviewed by the Radiation Safety Committee/HIRE", you may insert the appropriate language provided. If you use the exact wording as listed, the protocol and consent form will not need to be reviewed by the Radiation Safety Committee subcommittee (HIRE - Human Investigations Involving Radiation Exposure). You must however, send them an electronic copy of the protocol and consent form(s) after the study is approved by the HIC.
    • The electronic copy should be sent to Goode, Allen R. at arg2n@hscmail.mcc.virginia.edu. Please state in the email that your study does not require review and reference the consent language used.

  • If this study involves the use of ionizing radiation other than those listed on this page, patient dose(s) must be calculated. Please contact Goode, Allen R. at arg2n@hscmail.mcc.virginia.edu for assistance.

  • Use a radioactive drug that has an IND # or is IND exempt and is to be used in clinical or therapeutic study, must be approved by the HIRE.

  • Use of an FDA approved radiopharmaceutical for something that is outside the range of indicated uses, and is for clinical or therapeutic studies, must be approved by HIRE.

  • Investigational or research use of diagnostic X-rays or radiotherapy, i.e., not medically indicated, must be reviewed by HIRE.

  • If the study involves exposure from radiation that is from a procedure that is not standard of care and is from administration of FDA approved radioactive drugs or use of X-ray producing equipment, it must be approved by HIRE.

  • Use of a radioactive drug/pharmaceutical that has not been approved by the FDA as an agent approved for human use or does not have an investigative new drug application approved and on file with FDA and is not going to be used for therapeutic or clinical purposes, must be approved by the RDRC.

Examples of this type of use are: a research project intended to obtain basic information regarding the metabolism (including kinetics, distribution, and localization ) of a radioactively labeled drug or regarding human physiology, pathophysiology or biochemistry , but not intended for immediate therapeutic, diagnostic or similar purposes or to determine the safety and effectiveness of the drug in humans for such purposes (i.e. to carry out a clinical trial) Certain basic research studies, e.g. studies to determine whether a drug localizes in a particular organ or fluid space and to describe the kinetics of that localization , may have eventual therapeutic or diagnostic implications, but the initial studies are considered to be basic research.

Note: This committee is appointed by the Medical Center and its members must be approved by the FDA.

Uses of Ionizing Radiation That Do Not Need to Be Reviewed By HIRE

The following consent language may be used for protocols that involve a single X- ray procedure and involve exposure to ionizing radiation that results in a total effective dose to the study participant that is less than or equal to 300 mrem (millirem)*.

Abdominal X-Ray (1 film)
"This study involves radiation exposure from an abdominal x-ray. As part of everyday living, everyone is exposed to a small amount of background radiation. Background radiation comes from space and naturally-occurring radioactive minerals. The radiation dose you will receive in this study will give your body the equivalent of about 150 days' worth of this natural radiation. This radiation dose is what you will receive from this study only and does not include any exposure you may have received or will receive from other tests. The risk from this dose is considered small. This radiation exposure is not necessary for your medical care but is necessary to obtain the research information desired."

Barium Swallow (24 images)
"This study involves radiation exposure from x-rays of your stomach. As part of everyday living, everyone is exposed to a small amount of background radiation. Background radiation comes from space and naturally-occurring radioactive minerals. The radiation dose you will receive in this study will give your body the equivalent of about 240 days' worth of this natural radiation. This radiation dose is what you will receive from this study only and does not include any exposure you may have received or will receive from other tests. The risk from this dose is considered small. This radiation exposure is not necessary for your medical care but is necessary to obtain the research information desired."

Chest X-Ray (PA)
"This study involves radiation exposure from a chest x-ray. As part of everyday living, everyone is exposed to a small amount of background radiation. Background radiation comes from space and naturally-occurring radioactive minerals. The radiation dose you will receive in this study will give your body the equivalent of about 3 days' worth of this natural radiation. This radiation dose is what you will receive from this study only and does not include any exposure you may have received or will receive from other tests. The risk from this dose is considered small. This radiation exposure is not necessary for your medical care but is necessary to obtain the research information desired."

Chest X-Ray (PA + lat)
"This study involves radiation exposure from chest x-rays. As part of everyday living, everyone is exposed to a small amount of background radiation. Background radiation comes from space and naturally-occurring radioactive minerals. The radiation dose you will receive in this study will give your body the equivalent of about 10 days' worth of this natural radiation. This radiation dose is what you will receive from this study only and does not include any exposure you may have received or will receive from other tests. The risk from this dose is considered small. This radiation exposure is not necessary for your medical care but is necessary to obtain the research information desired."

DEXA (Bone Mineral Densities)
"This study involves radiation exposure from a DEXA (insert type of scan as shown below). As part of everyday living, everyone is exposed to a small amount of background radiation. Background radiation comes from space and naturally-occurring radioactive minerals. The radiation dose you will receive in this study will give your body the equivalent of about (use list below) of this natural radiation. This radiation dose is what you will receive from this study only and does not include any exposure you may have received or will receive from other tests. The risk from this dose is considered small. This radiation exposure is not necessary for your medical care but is necessary to obtain the research information desired."

Fontaine Imaging Center Hologic QDR Series Machines

  • For any one of the following scans: PA Lumbar Spine, Lateral Lumbar Spine, Hip, Whole Body or Forearm - use "less than 1 day"
  • For a pQCT - use "less than 1 day"

Note: If the machine or type of scan is not listed above, please contact Radiation Safety (2-4917) for further information.

Extremity (Hand/Foot) X-Ray
"This study involves radiation exposure from an extremity (hand, foot, etc.) x-ray. As part of everyday living, everyone is exposed to a small amount of background radiation. Background radiation comes from space and naturally-occurring radioactive minerals. The radiation dose you will receive in this study will give your body the equivalent of about 1 days' worth of this natural radiation. This radiation dose is what you will receive from this study only and does not include any exposure you may have received or will receive from other tests. The risk from this dose is considered small. This radiation exposure is not necessary for your medical care but is necessary to obtain the research information desired."

Head CT Scan
"This study involves radiation exposure from a CT scan (x-ray) of your head. As part of everyday living, everyone is exposed to a small amount of background radiation. Background radiation comes from space and naturally-occurring radioactive minerals. The radiation dose you will receive in this study will give your body the equivalent of about 240 days' worth of this natural radiation. This radiation dose is what you will receive from this study only and does not include any exposure you may have received or will receive from other tests. The risk from this dose is considered small. This radiation exposure is not necessary for your medical care but is necessary to obtain the research information desired."

Hip X-Ray
"This study involves radiation exposure from an x-ray of your hip. As part of everyday living, everyone is exposed to a small amount of background radiation. Background radiation comes from space and naturally-occurring radioactive minerals. The radiation dose you will receive in this study will give your body the equivalent of about 100 days' worth of this natural radiation. This radiation dose is what you will receive from this study only and does not include any exposure you may have received or will receive from other tests. The risk from this dose is considered small. This radiation exposure is not necessary for your medical care but is necessary to obtain the research information desired."

Knee X-Ray
"This study involves radiation exposure from an x-ray of your knee. As part of everyday living, everyone is exposed to a small amount of background radiation. Background radiation comes from space and naturally-occurring radioactive minerals. The radiation dose you will receive in this study will give your body the equivalent of about 100 days' worth of this natural radiation. This radiation dose is what you will receive from this study only and does not include any exposure you may have received or will receive from other tests. The risk from this dose is considered small. This radiation exposure is not necessary for your medical care but is necessary to obtain the research information desired."

Mammography (Standard 4 Views)
"This study involves radiation exposure from an x-ray of you breasts. As part of everyday living, everyone is exposed to a small amount of background radiation. Background radiation comes from space and naturally-occurring radioactive minerals. The radiation dose you will receive in this study will give your body the equivalent of about 40 days' worth of this natural radiation. This radiation dose is what you will receive from this study only and does not include any exposure you may have received or will receive from other tests. The risk from this dose is considered small. This radiation exposure is not necessary for your medical care but is necessary to obtain the research information desired."

Sinus Radiographs (3 View Plane Films)
"This study involves radiation exposure from 3 x-rays of your sinus. As part of everyday living, everyone is exposed to a small amount of background radiation. Background radiation comes from space and naturally-occurring radioactive minerals. The radiation dose you will receive in this study will give your body the equivalent of about 70 days' worth of this natural radiation. This radiation dose is what you will receive from this study only and does not include any exposure you may have received or will receive from other tests. The risk from this dose is considered small. This radiation exposure is not necessary for your medical care but is necessary to obtain the research information desired."

Note: If a single film is required, then the radiation dose and calculated percentage of the yearly background dose may be reduced by a third and the consent risk statement adjusted accordingly.

*mrem - unit of measurement of dose (how much energy is absorbed by the body from radiation)

MRI Scan
There is NO RADIATION exposure to a patient who receives an MRI scan, however, standard language is provided below for use in the consent form.

MRI scanning is a painless procedure that only requires that you lie quietly on a padded table that gently glides you into a large magnet.

While the scanner is performing your scan, you will hear some humming and thumping sounds. These are normal and should not worry you. Because of the magnetic field and radio frequencies, people with a heart pacemaker, brain, aneurysm clips, and some implanted metallic or electrical devices should NOT have an MRI. It is important that you inform the technologist if you have any of these metallic appliances. Please inform the technologist if you are pregnant or think that you may be pregnant. You also may need to have dye placed in your vein, and the technologist performing your scan will discuss this with you at the time of your scan.

Guidance for IRB (HSR) Protocols Involving the Use of Ionizing Radiation

The Radiation Safety Committee (RSC) is charged by Federal and State regulatory agencies to oversee the use of ionizing radiation at the University of Virginia. Sources of ionizing radiation include both radioactive materials and radiation-producing devices. Examples of uses of these sources include (but are not limited to) chest x-rays, DEXA scans, CT scans, fluoroscopy, and nuclear medicine procedures.

If uses of radiation or radioactive materials do not meet the criteria for "medically indicated," they are regarded as "indicated for research" and the RSC must review the protocol. Use of ionizing radiation in human research in any manner that does not directly benefit the patient/subject (i.e. beyond standard of care) must be approved by the RSC, specifically the Human Investigations Involving Radiation Exposure (HIRE) subcommittee or the Radioactive Drug Research Committee (RDRC).

To comply with FDA and DHHS guidelines and regulations, the University IRB must assure that the patient/subject enrolled in an investigational study is adequately informed about risk. Since the use of ionizing radiation in humans is associated with health risks in proportion to the amount of radiation received, it is the responsibility of the Principal Investigator (PI) to inform the IRB of any ionizing radiation procedures employed in the study. Additionally, the PI will be required to identify those ionizing radiation procedures that are beyond routine standard of care and for research purposes only (i.e. procedures that do not directly benefit the patient/subject).

Beneficence obligates the researcher to secure the well-being of all study participants. It is your responsibility to protect participants from harm, as well as ensure that they experience the possible benefits of involvement. Balancing risk and benefits is an important consideration. The key, according to the 1979 Belmont Report on the protection of human subjects, is to "maximize possible benefits and minimize possible harms." When do the benefits to society outweigh the possible risks of research? This is an ethical question that researchers face. The peer review process via this worksheet, and the principle of beneficence help you answer this question and protect your research participant's rights. The responsibility to protect and inform research participants is ultimately yours and cannot be ignored or delegated. Although you may delegate various tasks to certain team members, you cannot delegate the responsibility of protecting and informing participants of their rights. Submittal of your protocol and consent form to the RSC is a peer review process designed to assist you in providing the appropriate consent language for the radiation dose that will be received by the participants in your study.

Consent Language

Once the total radiation dose to the subject has been calculated, the appropriate consent language will be chosen from the templates shown below.

Dose Limits

Please be aware of the following dose limits for use of radiopharmaceuticals that are approved by the RDRC subcommittee of the RSC.

Title 21 - FDA Part 361 (b)(3)(i), Limit on radiation dose
The amount of radioactive material to be administered shall be such that the subject receives the smallest radiation dose with which it is practical to perform the study without jeopardizing the benefits to be obtained from the study. Under no circumstances may the radiation dose to an adult research subject from a single study, or cumulatively from a number of studies conducted within 1 year be generally recognized as safe if such dose exceeds the following:

  • 3 rem per single administration or study to the whole body, blood-forming organs, lens of the eye, and gonads; and 5 rem annually.
  • For other organs, the limits are 5 rem per single administration or study, and 15 rem annually.
  • For minors (under the age of 18), limits are 1/10th the adult values.

Template Consent Language for Radiation Risks

Template consent language (based on the calculated Total Dose Equivalent) to insert into your consent form under Radiation Risks.

Note: Average annual background dose in Charlottesville assumed to be 300 mrem/yr or 0.82 mrem/day)

Template A (Total Effective Dose less than or equal to 300 mrem)

"This study involves radiation exposure from (insert type of procedure or procedures involving radiation exposure). As part of everyday living, everyone is exposed to a small amount of background radiation. Background radiation comes from space and naturally-occurring radioactive minerals. The radiation dose you will receive in this study will give your body the equivalent of about (insert number of days) worth of this natural radiation. This radiation dose is what you will receive from this study only and does not include any exposure you may have received or will receive from other tests. The risk from this dose is considered small. This radiation exposure is not necessary for your medical care but is necessary to obtain the research information desired."

Template B (300 mrem < Total effective dose = or < 5 rem)

"This study involves radiation exposure from (insert maximum number) injections (scans or repetition) of (insert quantity of radioactive material, in units of millicuries; or type of x-ray procedure).

[Using the standard way of describing radiation dose, from participating in this study, you will receive a total of XX rem to your (insert highest-dosed organ), XX rem to your (insert 2nd highest-dosed organ), and XX rem to your (insert 3rd highest-dosed organ). All other organs will receive smaller amounts of radiation.]

[Although each organ will receive a different dose,] the total effective radiation dose you will receive from these procedures is approximately XX rem. For comparison this dose is (XX times or XX% of) the annual radiation dose safely allowed for a radiation worker such as the person performing your (type of procedure). This radiation dose is what you will receive from this study only and does not include any exposure you may have received or will receive from other tests. The precise risk from this dose is not known but is thought to be small. This radiation exposure is not necessary for your medical care but is necessary to obtain the research information desired."

If you are pregnant [or breastfeeding], you may not participate in this research study. It is best to avoid radiation exposure to unborn [or nursing] children since they are more sensitive to radiation than adults."

Template C (Total effective dose > 5 rem)

"This study involves radiation exposure from (insert maximum number) injections (scans or repetition) of (insert quantity of radioactive material, in units of millicuries; or type of x-ray procedure).

Optional paragraph: Some organs will receive higher doses than others. you will receive of XX mSv to your (insert highest-dosed organ), XX mSv to your (insert 2nd highest-dosed organ), and XX mSv to your (insert 3rd highest-dosed organ). All other organs will receive smaller amounts of radiation.]

The total effective radiation dose you will receive from these scans is approximately (insert effective dose in mSv). For comparison, this dose is about (insert fraction of or multiple of) the annual radiation dose that is safely allowed for a radiation worker such as the person performing your scans. The precise risk from this dose is not known but is thought to be small. This radiation dose is what you will receive from this study only and does not include any exposure you may have received or will receive from other tests. This radiation exposure is not necessary for your medical care but is necessary to obtain the research information desired
If you are pregnant [or breastfeeding], you may not participate in this research study. It is best to avoid radiation exposure to unborn [or nursing] children since they are more sensitive to radiation than adults."

Optional language if total dose is uncertain, therapy doses, etc.:

"This study involves radiation exposure from (insert type of X-ray procedure) of your (insert area of the body). The total effective radiation dose from just one of each of these scans is approximately (insert dose). The highest radiation doses are from the (insert type of X-ray procedure). Additional scans and X-rays will add additional dose. It is uncertain how many CTs and X-rays total you will need throughout the study. The possible benefits from the study should be weighed against the possible detrimental effects of radiation, including an increased risk of cancer at higher doses. 

Myth: Informed consent is designed primarily to protect the legal interests of the research team.

Reality: The purpose of the process is to protect you and other participants by providing access to information that can help you make an informed choice. It also is designed to make you aware of your rights as a participant

Myth: Medical personnel are busy, so I can't really expect them to keep me informed as the trial progresses or listen to my questions.

Reality: The research team has a duty to keep you informed, make sure that you understand the information they provide, and answer your questions. If you ever feel that you are not getting what you need, do not hesitate to speak up. You will be given the name and phone number of a key contact person who can answer your questions throughout the course of the trial. Keep in mind that people like you are making this research possible through their willingness to participate.

Both the participant and the research team have a responsibility to be informed regarding the risks associated with the radiation exposure involved in this study. The following information is provided to increase your understanding of radiation exposure and the risks associated with the exposure.

Information for doctors: http://www.icrp.org/docs/Rad_for_GP_for_web.pdf

Information on Radiation Exposure for University Virginia Research Subjects and the Research Team

The average person in the United States receives a radiation dose of about 0.3 rem (or 300 mrem) per year from natural background sources, such as from the sun, outer space, and from radioactive materials that are found naturally in the earth's air and soil.

The effects of radiation exposure on humans have been studied for over 60 years. In fact, these studies are the most extensive ever done of any potentially harmful agent that could affect humans. In all these studies, no harmful effect to humans has been observed from the levels of radiation less than 5 - 10 rem. However, scientists still disagree on whether radiation doses at these levels are harmful.

One possible effect that could occur at these doses is a slight increase in the risk of cancer. Please be aware that the natural chance of a person getting a fatal cancer during his/her lifetime is about 1 out of 4 (or 25 percent).

One concern some people may have about radiation exposure is the effect on fertility or on the possibility of causing harm to future children (i.e., genetic risk). Doses of 5 - 10 rem are well below the levels that affect fertility. In addition, genetic effects have not been seen in humans who have been exposed to radiation. The information on genetic effects currently available is based on animal experiments using doses of radiation much higher than the amount you will receive in this study.

It is best to avoid radiation exposure to unborn or nursing children since they are more sensitive to radiation than adults.

There continues to be absence of scientific certainty regarding the relationship between low doses and health effects. Consequently, the scientific community generally makes the conservative assumption that any exposure to ionizing radiation can cause biological effects that may be harmful to the exposed person and that the magnitude or probability of these effects is directly proportional to the dose. These effects may be classified into three categories.

Somatic Effects: Physical effects occurring in the exposed person. These effects may be observable after a large or acute dose (e. g., 100 rem (1 Sv) or more to the whole body in a few hours); or they may be effects such as cancer that may occur years after exposure to radiation.

Genetic Effects: Abnormalities that may occur in the future children of exposed individuals and in subsequent generations (genetic effects exceeding normal incidence have not been observed in any of the studies of human populations).

Teratogenic Effects: Effects such as cancer or congenital malformation that may be observed in children who were exposed during the fetal and embryonic stages of development (these effects have been observed from high, i.e., above 20 rem (0.2 Sv), acute exposures).

The normal incidence of effects from natural and manmade causes is significant. For example, approximately 20% of people die from various forms of cancer whether or not they ever receive occupational exposure to radiation.

When radioactive materials enter the body, they go to various organs or are excreted from the body, depending on the biochemistry of the material. Most materials used in medicine are excreted from the body in a few days.

When x-rays, gamma rays, and ionizing particles interact with living materials such as our bodies, they may deposit enough energy to cause biological damage. Radiation can cause several different types of events such as the very small physical displacement of molecules, changing a molecule to a different form, or ionization, which is the removal of electrons from atoms and molecules. When the quantity of radiation energy deposited in living tissue is high enough, biological damage can occur as a result of chemical bonds being broken and cells being damaged or killed. These effects can result in observable clinical symptoms.

The human body has a remarkable ability to repair damaged cells in the body. Events that occur in a cell, when damaged by radiation, can result in:

  • cell repair with no permanent damage,
  • cell death (much like the large number of cells that die every day in the body and are replaced by normal biological processes), or
  • a change in the cell's reproductive structure causing a mutation.

The body can usually repair or destroy the mutated cell with no permanent damage, or the mutated cell can become precancerous, which could go on to become cancerous. Ionizing radiation is only one of many agents with the potential for causing cancer. There are several everyday products we buy and use that have potentially cancer causing chemical agents in them. It is important to note that mutations in cells do not always cause cancer. Some cell changes are benign or the cell may die. These changes do not lead to cancer.

Health effects from exposure to radiation range from no effect at all, to death, including diseases such as leukemia or bone, breast, and lung cancer. Very high (100s of rads), short-term doses of radiation have been known to cause prompt (or early) effects, such as vomiting and diarrhea, skin burns, cataracts and even death.

What is the difference between acute and chronic radiation dose?

Acute radiation dose usually refers to a large dose of radiation received in a short period of time. Chronic dose refers to the sum of small doses received repeatedly over long time periods, for example, 20 mrem (or millirem, which is 1-thousandth of a rem) (0.2 mSv) per week every week for several years. For example, a dose to the whole body of about 300-500 rads (3-5 Gy), more than 60 times the annual occupational dose limit, if received within a short time period (e.g., a few hours) will cause vomiting and diarrhea within a few hours; loss of hair, fever, and weight loss within a few weeks; and about a 50 percent chance of death if medical treatment is not provided. These effects would not occur if the same dose were accumulated gradually over many weeks or months. Thus, one of the justifications for establishing annual dose limits is to ensure that occupational dose is spread out in time.

It is assumed for radiation protection purposes that any radiation dose, either acute or chronic, may cause delayed effects. However, only large acute doses cause early effects; chronic doses within the occupational dose limits do not cause early effects. A radiation dose may be caused by exposure to radiation that originates outside the body, called "external exposure," or by exposure to radiation from radioactive material that has been taken into the body, called "internal exposure".

It is the current scientific consensus that a rem of radiation dose has the same biological risk regardless of whether it is from an external or an internal source. The sum of external and internal dose is called the total effective dose equivalent (TEDE) and is expressed in units of rem.

We don't know exactly what the chances are of getting cancer from a low-level radiation dose, primarily because the few effects that may occur cannot be distinguished from normally occurring cancers. However, we can make estimates based on extrapolation from extensive knowledge from scientific research on high dose effects. The estimates of radiation effects at high doses are better known than are those of most chemical carcinogens.

From currently available data, the NRC has adopted a risk value for an occupational dose of 1 rem (0.01 Sv) Total Effective Dose Equivalent (TEDE) of 4 in 10,000 of developing a fatal cancer, or approximately 1 chance in 2,500 of fatal cancer per rem of TEDE received. The uncertainty associated with this risk estimate does not rule out the possibility of higher risk, or the possibility that the risk may even be zero at low doses and dose rates, It is important to understand the probability factors here. A similar question would be, "If you select one card from a full deck of cards, will you get the ace of spades?" This question cannot be answered with a simple yes or no. The best answer is that your chance is 1 in 52. However, if 1000 people each select one card from full decks, we can predict that about 20 of them will get an ace of spades, Each person will have 1 chance in 52 of drawing the ace of spades, but there is no way we can predict which persons will get that card. The issue is further complicated by the fact that in a drawing by 1000 people, we might get only 15 successes, and in another, perhaps 25 correct cards in 1000 draws. We can say that if you receive a radiation dose, you will have increased your chances of eventually developing cancer. It is assumed that the more radiation exposure you get, the more you increase your cancer? Probably not. Based on the risk estimates previously discussed, the risk of cancer from doses below the occupational limits is believed to be small.

Assessment of the cancer risks that may be associated with low doses of radiation are projected from data available at doses larger than 10 rem (0.1 Sv). We have data on cancer probabilities only for high doses. Only in studies involving radiation doses above occupational limits are there dependable determinations of the risk of cancer.

For regulatory purposes, the NRC uses a dose response curve which shows the number of effects decreasing linearly as the dose decreases. Because the scientific evidence does not conclusively demonstrate whether there is or is not an effect at low doses, the NRC assumes for radiation protection purposes, that even small doses have some chance of causing cancer. Thus, a principle of radiation protection is to do more than merely meet the allowed regulatory limits; doses should be kept as low as is reasonably achievable (ALARA). This is as true for natural carcinogens such as sunlight and natural radiation as it is for those that are manmade, such as cigarette smoke, smog, and x-rays.

To help put the risks of radiation in perspective with other every day risks, the following table is provided:

Estimated Loss of Life Expectancy from Health Risks

Health Risk Estimate of Life
Expectancy Lost
average)
Smoking (20 cigarettes a day) 6 years
Overweight (by 15 %) 2 years
Alcohol consumption (U.S.A.) 1 year
All accidents combined 1 year
Motor vehicle 207 days
Home accidents 74 days
Drowning 24 days
All natural hazards
(earthquake, lightning, etc.)
7 days
Medical radiation 6 days
Occupational Exposure ----
0.3 rem/yr from age 18 to 65 15 days
1 rem/yr from age 18 to 65 51 days

These estimates are considered by the Regulatory community to be the best available for the worker to use to make an informed decision concerning the acceptance of the risks associated with exposure to radiation. Compared to many other occupations and their associated occupational hazards such as construction work or law enforcement, the hospital radiation workers' risk to occupational radiation exposure is considered to be relatively small.

According to the newly released NCRP report # 160 (March 2009), the medical radiation exposure to US population has increased by nearly 6 times compared to the previous NCRP publication (NCRP 93). The previous pie-chart published in 1987 (NCRP report #93) indicated contribution of 3 mSv from background radiation, 0.53 mSv from medical exposure and 0.07 mSv from other sources (consumer products, occupational and other sources) exposure while the new pie-chart published in March 2009 (NCRP report #160) indicates contribution of 3.1 mSv from background radiation and 3.0 mSv from medical and 0.1 mSv from all other sources (consumer products, occupational and other sources). The largest contributor to the collective dose to US population is from CT and Nuclear Medicine. CT scanning has increased nearly 10-11% annually in the US in the past two decade. The number of CT procedures has increased from 3 million CT scans in 1980 to more than 69 million CT scans in 2007.

pie_chart
NCRP Report 160, March 2009

 
 
Special Materials Handling Facility
515 Edgemont Road
Charlottesville, VA 22904-4322
PHONE 434.982.4911
FAX 434.982.4915
One Morton Drive
Suite 320
Charlottesville, VA 22904-4322
PHONE 434.243.1711
FAX 434.243.1735
EMAIL vck9u@virginia.edu
© 2017 By The Rector And Visitors Of The University Of Virginia