Radiological Dispersal Devices (RDDs)
Radiological Dispersal Devices (RDDs):
Dirty Bomb, Other Dispersal Methods
- Radiological Dispersal Device (RDD) is any device that causes the purposeful dissemination of radioactive material without a nuclear detonation.
- Dispersion methods can be
- "Dirty Bomb" = Explosive method of dispersion (See Figure 1)
- Explosion produces radioactive and nonradioactive shrapnel and radioactive dust
- Explosion causes
- Radiation contamination, commonly (Animations)
- Radiation exposure only in certain circumstances (Animations)
- Physical injury
- Burns
- Panic, fear
Figure 1. Dirty Bomb: Radiological Dispersal Device Using Explosive
- Other Dispersal Methods
- Passive or active dispersion of unsealed radioactive sources, e.g., deposit in soil or water, drop from airborne device (See Figure 2)
- Radioactive sources can be solid, aerosol, gas, or liquid
- Contamination of people may occur via air, water, soil, or food
Figure 2. Dispersal of Radioactive Material by Aircraft
- Explosive RDDs cannot cause mass casualties on the scale of a nuclear explosion. All or most fatalities or injuries will probably due to explosion itself.
- While large numbers of people in a densely populated area around the detonation of a RDD might become contaminated and require decontamination, few if any will be contaminated to a level that requires medical treatment.
- Local health authorities will have to assess the persons who were very close to the point of release for the need for medical intervention.
- The health and environmental consequences from RDDs, will depend on
- The design of the device
- Type and quantity of radioactive material
- The pattern of dispersion following the release
- RDDs may affect
- Small, localized areas (e.g., a street, single building, or city block)
- Large areas, up to several square miles, depending on the nature of the dispersion and the amount and type of radioactive material
- Other hazards may also be present
- Fire, smoke, shock, shrapnel (from an explosion)
- Industrial chemicals
- Secondary device
- Radioactive decontamination of persons and areas affected may be required.
References:
- Harper FT, Musolino SV, Wente WB. Realistic radiological dispersal device hazard boundaries and ramifications for early consequence management decisions. Health Phys. 2007 Jul;93(1):1-16. [PubMed Citation]
- Smith JM, Ansari A, Harper FT. Hospital management of mass radiological casualties: reassessing exposures from contaminated victims of an exploded radiological dispersal device. Health Phys. 2005 Nov;89(5):513-20. [PubMed Citation]
- Musolino SV, Harper FT. Emergency Response Guidance for the First 48 Hours after the Outdoor Detonation of an Explosive Radiological Device. Health Physics 2006 Apr;90(4):377-85. [PubMed Citation]
- Management of Terrorist Events Involving Radioactive Material, National Council on Radiation Protection and Measurements, NCRP Report No. 138, Bethesda, MD, 2001.
- Management of Persons Accidentally Contaminated with Radionuclides, National Council on Radiation Protection and Measurements, NCRP Report No. 65, Bethesda, MD, 1980.
- Handbook for responding to a radiological dispersal device first responders's guide — the first 12 hours (PDF - 4.26 MB). (Conference of Radiation Control Program Directors, Inc., September 2006)
- Department of Homeland Security Working Group on Radiological Dispersal Device (RDD) Preparedness, Medical Preparedness and Response Sub-Group, 12/09/03 Version (PDF - 335 KB).
- Radiological Dispersal Device (PDF - 380 KB) (Human Health Fact Sheet, Argonne National Laboratory, August 2005)
- FAQs About Dirty Bombs (HHS/CDC, 05/10/2006)
- Backgrounder on Dirty Bombs (NRC)
- Tochner ZA,Lehavi O,Glatstein E, Radiation Bioterrorism, in Harrison's Principles of Internal Medicine, 16th Edition, Kasper DL, et al. (Eds.), New York, McGraw-Hill, 2004, pp. 1294-1300.
- Patient Decontamination: Recommendations for Hospitals (PDF - 124 K) (The Hospital and Healthcare System Disaster Interest Group and the California Emergency Medical Services Authority, July 2005, EMSA #233, Radiological Contamination, pages 11-16)
- Marcus CS, Siegel JA, Sparks RB. Medical Management of Radiocontaminated Patients (PDF - 1.36 MB) (Los Angeles County Department of Health Services, Emergency Medical Services Agency, June 2006)
- Marcus, CS. Administration of decorporation drugs to treat internal radionuclide contamination: medical emergency response to radiologic incidents. RSO Magazine, 2004;9(5):9-15. (PDF - 34 KB)
- Radiological Attack — Radiological Dispersal Devices (PDF - 127 KB) (The California Emergency Medical Services Authority)
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Potential Isotopes Used in RDDs
Basic Radiological Properties of RDD Isotopes
Basic Radiological Properties of Nine Key Radionuclides for RDDs |
|---|
Isotope |
Half-Life
(years) |
Specific Activity
(Ci/g) |
Decay Mode |
Radiation Energy (MeV) |
Alpha
(α) |
Beta
(β) |
Gamma
(γ) |
Americium-241 |
430 |
3.5 |
α |
5.5 |
0.052 |
0.033 |
Californium-252 |
2.6 |
540 |
α (SF, EC) |
5.9 |
0.0056 |
0.0012 |
Cesium-137 |
30 |
88 |
β, IT |
- |
0.19, 0.065 |
0.60 |
Cobalt-60 |
5.3 |
1,100 |
β |
- |
0.097 |
2.5 |
Iridium-192 |
0.2 (74 d) |
9,200 |
β, EC |
- |
0.22 |
0.82 |
Plutonium-238 |
88 |
17 |
α |
5.5 |
0.011 |
0.0018 |
Polonium-210 |
0.4 (140 d) |
4,500 |
α |
5.3 |
- |
- |
Radium-226 |
1,600 |
1.0 |
α |
4.8 |
0.0036 |
0.0067 |
Strontium-90 |
29 |
140 |
β |
- |
0.20, 0.94 |
- |
SF = spontaneous fission;
IT = isomeric transition;
EC = electron capture.
A hyphen means not applicable.
The radiation energies for cesium-137 include the
contributions of barium-137 metastable (Ba-137m),
and those for strontium-90 include the contributions
of yttrium-90.
|
Adapted from Radiological Dispersal Device (PDF - 380 KB) Human Health Fact Sheet, Argonne National Laboratory, August 2005
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Potential RDD Effects
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Radiation Response Worker Exposure Guidelines
Total Effective Dose Equivalent (TEDE)
Guideline |
Activity |
Condition |
5 rem |
All occupational exposures |
- Dose limit to emergency workers: 5 rem
- Use all reasonable measures to minimize dose
- For most Radiological Dispersal Devices, radiation control measures will maintain exposures below 5 rem
- Some rescues may involve exposures > 5 rem
- When 5 rem limit is exceeded, worker monitoring must be made available and volunteers for such activities should be made fully aware of the risks
|
10 rem |
Protecting valuable property necessary for public welfare (e.g., a power plant) |
- Exposures to emergency workers protecting valuable property necessary for public welfare may exceed 5 rem
- Use all reasonable measures to minimize dose
- When 5 rem limit is exceeded, worker monitoring must be made available and volunteers for such activities should be made fully aware of the risks
- For potential doses > 10 rem, special medical monitoring programs should be employed, and exposure should be tracked in terms of the unit of absorbed dose (rad) rather than TEDE (rem).
|
25 rem |
Lifesaving or protection of large populations |
- During large incidents (e.g., Improvised Nuclear Devices) exposures to emergency workers may exceed 5 rem
- Emergency response activities may include: lifesaving, protection of large populations, prevention of mass spread of destruction
- Use all reasonable measures to minimize dose
- When 5 rem limit is exceeded, worker monitoring must be made available and volunteers for such activities should be made fully aware of the risks
- For potential doses > 10 rem, special medical monitoring programs should be employed, and exposure should be tracked in terms of the unit of absorbed dose (rad) rather than TEDE (rem).
|
1 Adapted from Planning Guidance for Protection and Recovery Following Radiological Dispersal Device (RDD) and Improvised Nuclear Device (IND) Incidents (PDF - 394 KB) (DHS/FEMA, published in Federal Register, August 1, 2008, Z-RIN 1660-ZA02)
2 Emergency response decisions resulting in worker exposure doses greater than 5 rem
- Made by on-scene Incident Commander during incident when exceeding 5 rem is unavoidable
- Reflect actual incident circumstances/worker activity (e.g., need to save lives or critical infrastructure)
- Require informed consent from responding worker
3 Decision points for restricting response workers' activities have been recommended by various other agencies.
Agency |
Summary Information |
Original Document |
|---|
National Council on Radiation Protection and Measurement (NCRP) |
NCRP Radiation Protection Guidelines: Control of Radiation Dose in the Control Zones |
Key Elements of Preparing Emergency Responders for Nuclear and Radiological Terrorism (NCRP Commentary No. 19, December 2005, page 19, purchase required; see Free Overview (PDF - 219 KB)) |
International Atomic Energy Agency (IAEA) |
IAEA Emergency Worker Turn-back Dose Guidance |
Manual for First Responders to a Radiological Emergency (PDF - 2.2 MB) (CTIF, IAEA, PAHO, WHO, October 2006, page 41) |
Conference of Radiation Control Program Directors, Inc. (CRCPD) |
CRCPD Turn-back Exposure Rates and Dose Guidelines |
Handbook for Responding to a Radiological Dispersal Device (Dirty Bomb): First Responder's Guide: The First 12 Hours (CRCPD Publication 06-6) (PDF - 4.26 MB), page 28. Conference of Radiation Control Program Directors, Inc. Frankfort, Kentucky, 2006. |
International Commission on Radiological Protection (ICRP) |
ICRP Guidance for Occupational Exposure |
Protecting People Against Radiation Exposure in the Event of a Radiological Attack (International Commission on Radiological Protection, ICRP Publication 96, 2005, page 51) |
See also:
Personal Protective Equipment (PPE)
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