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C-1 APPENDIX C Radiological Threat Information C.1 HUMAN HEALTH EFFECTS AND In a radiation field of "X" mrem/hour, the total dose one re- PROTECTION FROM RADIATION ceives is the time of exposure multiplied by the dose rate. Therefore, the shorter the exposure time, the smaller the dose. Since the discovery and use of radium and radiation around Since radiation emanates in all directions from radioactive the beginning of the 20th century, many medical studies have materials, the dose rate from a radiation source decreases as been performed to determine the human health effects of radi- distance from it increases. Placing the right kind of shielding ation doses. Radiation exposure is classified as either acute or between you and the radiation source will reduce the dose rate chronic where acute is a short time frame exposure on the and dose since the shielding absorbs or attenuates the radia- order of seconds to hours whereas chronic exposure is long- tion before it reaches you. The best shielding for gamma and term exposure over a period of years. A large acute or chronic X-ray radiation is heavy, high-density material (iron, steel, dose to the whole body can cause serious health effects in- lead, high-density concrete) while neutrons are best shielded cluding death whereas smaller chronic doses can cause cancer by materials which contain hydrogen or other light elements over periods of 10 to 50 years. Acute whole body radiation in a high density such as concrete, special plastic formula- dose human health effects are summarized in Table C-1. The tions, or water. The simplest of these three rules to follow in health effects of chronic radiation dose over a 50-year time pe- an emergency first response situation is to minimize time and riod, which increase the risk of lifetime latent cancer fatality is maximize distance. presented in Table C-2. It should be noted that radiation doses Protection from internal radiation hazards such as the in- to just one specific part or organ of the body may have differ- halation or ingestion of alpha or beta radiation emitting ra- ent and, sometimes, less life-threatening consequences. dioisotopes requires a different approach presented below. This table shows that insignificant health effects would be expected for acute doses up to 10 rem and a small percentage INTERNAL RADIATION HAZARD PROTECTION RULES of the general population would experience some discom- forting temporary symptoms for doses of 10 to 100 rem. Acute doses over 100 rem require medical intervention and become life threatening with more serious symptoms. WEAR RESPIRATORY PROTECTION Protection from radioactive material involves different WEAR ANTI-CONTAMINATION SUIT strategies for different types of radioactive hazards. External {WITH RESPIRATORY PROTECTION} gamma, X-ray, and neutron radiation hazards must be man- aged by using the three basic rules of radiation protection: time, distance, and shielding, which are explained below. These hazards are managed or mitigated by the use of respirators or professional air filtration masks along with anti-contamination (Anti-C) suits, which are plastic or EXTERNAL RADIATION HAZARD PROTECTION RULES other easily washed surface material full body suits that, MINIMIZE RADIATION EXPOSURE TIME along with boots and hoods, cover the entire body and pre- vent any deposition or inhalation of radioactive particles. High efficiency air filtration masks or independent air sup- ply masks may already be part of many first responders equipment (i.e., firefighters) or can easily be added to their MAXIMIZE DISTANCE FROM RADIATION SOURCES inventory. Anti-C suits are more complex, expensive, time consuming, and larger pieces of equipment for the trans- portation system first responder. Although important, the Anti-C suits should take a second priority to air filtration or independent air breathing masks. This is because the MAXIMIZE APPROPRIATE RADIATION SHIELDING masks will preclude the introduction of radioactive parti- cles inside the human body whereas the suits prevent the deposition of radioactive particles on the skin and hair of humans. It is much easier to decontaminate skin/hair of ra- dioactive particles than to remove inhaled or ingested ra- dioactive material.

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C-2 TABLE C-1 Acute Radiation Dose Human Health Effects Acute Dose to Whole Body Expected Human Health Effects (rem) <1 rem No health effects 1 to 10 rem No discernible health effects except for possible dry mouth, headaches and anxiety; insignificant increase in lifetime cancer risk, full recovery 10-100 Slight (<5%) incidence of nausea, vomiting, headache; temporary drop in white blood cell count; 0.5%-5% increase in lifetime cancer risk; full recovery 100-300 5-50% of population experience nausea and vomiting, long term drop in white blood cell count, fatigue, weakness, infection susceptibility, loss of appetite, skin reddening, hair loss, 5-15% increase in lifetime cancer fatality, some cataract formation, 5-10% population fatality within 30-60 days; significant medical care required for full recovery 300-500 50-100% of population experience nausea and vomiting, 10-50% population fatality within 30-60 days; hemorrhaging, extensive medical care may prevent mortality 500-800 Permanent sterilization, cataracts in 100% of population, 50-90% population fatality within 30-60 days; extreme medical care may prevent mortality 800-3000 Skin blistering, 90-100% population fatality in 2 to 3 weeks; little chance of survival with even most extreme and intensive medical care TABLE C-2 50-Year Chronic Radiation Dose Human Health Effects Total 50-Year Chronic Whole Expected Public Human Health Effects Body (Lifetime Probability of Latent Fatal Cancer) Radiation Dose (rem) 15 (natural background) 0.8% 50 [1 rem/year] 2.5% 100 [2 rem/year] 5% 1000 [20 rem/year] 50% C.2 NEAR TERM MEDICAL TREATMENT Although no drugs should be administered to members of FOR EXTERNAL RADIATION AND the public exposed to a radiological incident until the specific INTERNAL RADIOACTIVE radioisotope(s) involved have been identified, maintaining a CONTAMINATION stockpile of treatment drugs, which can be quickly accessed, Members of the public in proximity to a radiological threat could significantly reduce treatment time and the resulting can be treated so as to significantly reduce their individual ra- radiation dose to the public. diation dose. Rapid movement away from the location of ra- It should be noted that members of the public removed dioactive material will reduce doses based on the previously from the area around an RDD or ATS should be isolated from discussed basic rules of thumb regarding minimizing time the general public and uncontaminated areas. Even after skin and maximizing distance. Relocation to a controlled area and and hair decontamination by intense washing and removal of subsequent removal of all clothing and washing down all all clothing, humans may be secreting radioisotopes in their body surfaces will reduce contamination doses and mitigate liquid and solid wastes, which should also be controlled and inhalation or ingestion of radioactive particles. Since radia- isolated from the sewage system. tion doses can compromise the immune system, prompt treatment of all cuts and burns and the administration of ap- C.3 FEDERAL PUBLIC RADIATION propriate topical, oral, and injected antibiotics will prevent STANDARDS, REGULATIONS, AND possibly serious infections. GUIDANCE A number of drugs and chemicals have been recognized by medical authorities as being effective in the treatment of spe- Federal government agencies involved with handling, use, cific radioisotope internal contamination by inhalation, inges- and regulation of radioactive material have developed stan- tion, or absorption through open wounds. These drugs either dards, limits, and criteria for allowable public exposure to ra- saturate an organ of the body to prevent it from absorbing the diation. Separate, and more relaxed, standards exist for work- radioisotope or they rapidly increase the body's excretion of ers in the nuclear industry. However, transportation system the radioisotope. One drug can reduce the chance of latent responders to a radiological threat are not considered nuclear cancer due to radiation exposure only if administered before workers, but should be treated as the public in terms of radi- exposure and would therefore be useful for first responders ation dose limits. These radiation dose limits were all derived only. These are summarized in Table C-3. based on normal activities and operations or accidents at

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C-3 TABLE C-3 Approved Drugs or Chemicals for Radiation Treatment Inhaled or Ingested Drug or Chemical Treatment Form and Radioisotope or External Treatment Conditions Radiation Iodine-125 Potassium Iodide, Potassium Iodate, Pills or Sodium Iodide1 As soon as possible after exposure and daily for two weeks Cesium-137 Ferric Hexacyanoferrate (II) aka Solution or pill Prussian Blue Three times daily for three weeks Plutonium-238 Calcium or Zinc Solution intravenous or Americium-241 diethylenetriaminepentaacetate (Ca- as an inhaler Curium-244 DTPA2 or Zn-DTPA) or EDTA As soon as possible Californium-252 Daily for up to 5 days Strontium-90 Aluminum phosphate or barium Oral, as soon as possible sulfate Any Uranium isotope Sodium Bicarbonate IV or pills every four hours to protect kidneys Tritium (Hydrogen-3) Water Orally and/or IV forced fluids Gamma and neutron radiation Amifostine Intravenous at least one hour exposure (phosphorylated aminothiol) before exposure High radiation dose to bone Cytokines Pills or injection marrow (up to 11 days) 1 suitable alternative for individuals with potassium allergic reaction 2 preferred over Zn-DTPA and EDTA nuclear facilities, but not in the context of homeland security The PAG for early response to doses greater than 25 rem or radiological threats to transportation systems. Table C-4 assumes that this high dose is due to the inhalation and/or in- presents public radiation dose limits set forth and treated as gestion of radioactive iodine, which naturally concentrates law by different federal government agencies. in the body's thyroid and can cause thyroid cancer at high The federal public radiation dose limits in Table A.4 are a doses. Under medical supervision, the administration of non- small fraction of natural radiation for normal operations of radioactive iodine pills, usually in the form of potassium io- facilities that contain radioactive materials. The only excep- dide will saturate the thyroid with non-radioactive iodine and tion is that of a nuclear power plant accident, which allows mitigate any absorption of the radioactive iodine. This action significant, but non-fatal, public doses. It is also interesting will only be effective if radioactive iodine is involved. The first to note that transportation packages containing radioactive responder's radiation detection instrument will not determine material can have a significant dose rate, by DOT regulation. specific radioisotopes, only the magnitude of the radiation However, even if one were to be in contact with the maxi- dose rate field. mum allowed 200 mrem/hour package, it would take 500 hours (21 days) of continuous contact to receive a 100 rem dose where there is a small probability of death. It is impor- C.4 RADIOLOGICAL DISPERSAL DEVICE tant to note that none of the dose limits in Table 8.6 were de- RADIOISOTOPE PROPERTIES signed or intended for an RDD or ATS scenario. The EPA, in 1992, promulgated radiological protection guidance for Radioactive material, in the form of radioisotopes, are pro- state and local officials in the case of a non-nuclear weapon duced and used worldwide for industrial, research and med- nuclear incident. This guidance is in the form of Protective ical applications. The control and accounting of devices, Action Guides (PAGs), which are public doses at which spe- which contain radioisotopes, has not been subject to the same cific actions should be taken during an incident or emer- level as nuclear weapons and nuclear fuel. Worldwide, thou- gency. These EPA PAGs are presented in Table C-5. sands of radioisotope devices have been unaccounted for and For this study, only the EPA early incident phase is of in- provide an ideal source for radioactive material threats to terest. Therefore, first responders should be able to measure transportation. Several studies have been performed to de- any radiation dose rate such that continued public exposure in termine the most likely radioisotopes that could be used in a the area would result in a dose rate of 1 rem or greater. This radiological dispersal device (RDD). These radioisotopes is equivalent to a dose rate as low as about 1 mrem/hr. for a were selected based on their availability, half-life, radiolog- 4-day contiguous public presence and as high as 1 rem/hr. for ical hazard, and radiation energy. A list of the most likely a one-hour contiguous public presence. This requirement is RDD radioisotopes was synthesized from several sources met by the previously discussed radiation detection survey and presented in Table C-6 along with some key radiation meter specifications of 0.1or 1 mrem/hr. to 100 or 1000 rem/hr. properties.

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C-4 TABLE C-4 Federal Government Agency Public Radiation Dose Limits U.S. Type of Public Radiation Dose Public Limit or Federal Federal Criteria Regulation Agency (millirem) Citation Nuclear Regulatory Whole body from normal operations of 100 10 CFR 20.1301 Commission (NRC) NRC-licensed facilities; per year 10 CFR Special exemption for individual members 500 20.1301 of public per year NRC External dose rate in unrestricted area at 2 10 CFR NRC-licensed facility per hour 20.1301 NRC Whole body from cleanup and shutdown of 25 10 CFR 20.1403 NRC-licensed facility per year (/yr.) NRC Accident at nuclear power plant 10 CFR 100.11 -whole body 25,000/yr. - thyroid 300,000/yr. NRC Local skin surface dose 50,000/yr. 10 CFR 20 NRC Due to low level radioactive waste disposal 10 CFR 61.41 repository -whole body 25/yr. -thyroid 75/yr. -other organs 25/yr. Environmental Breathing air 10/yr. Protection Agency (EPA) EPA Drinking water 4/yr. 40 CFR 141.66 EPA Normal nuclear power plant operation 40 CFR 190.10 -whole body 25/yr. -thyroid 75/yr. -other organs 25/yr. EPA Spent nuclear fuel and radioactive waste 40 CFR 191.03 storage -whole body 25/yr. -thyroid 75/yr. other organs 25/yr. EPA Underground Uranium Mines 10/yr. 40CFR61(Sub B) EPA Department of Energy (DOE) Facilities 10/yr. 40CFR61 (Sub H) EPA National nuclear waste repository at Yucca 15/yr. 40 CFR 197 Mountain, Nevada Department of Dose rate at outer surface of vehicle package 200 49 CFR 173.441 Transportation (DOT) containing radioactive material per hour DOT Dose rate at 6.6 feet from the outer surface 10 49 CFR 173.441 of transport vehicle containing radioactive per hour material TABLE C-5 EPA Protective Action Guides (PAGs) for a Radiological Incident Incident Phase Public Dose (rem) Action Early (first 4 days) 1.0 to 5.0 Evacuation or Sheltering (whole body) Early 25.0 (thyroid) Administer Stable Iodine Intermediate 2.0 Relocation (4 days to one year) (whole body) Intermediate < 2.0 Apply Dose Reduction techniques (whole body) As previously discussed, radiation from an RDD can only signal processor, and display-controls. The detector, which be detected by specifically designed measurement instru- could be integral to the instrument or connected by wire to ments. There is a wide spectrum of radiation detectors avail- be hand held separately, produces an electric signal when ra- able, each of which is designed for a specific function. For diation enters it. No one single detector can measure alpha, the purposes of transportation system emergency response, beta, gamma, and neutron radiation. The electronic signal a general-purpose survey meter would be the most appro- processor converts the signal into an electric driver for the priate instrument. Each radiation-measuring instrument display panel. The display-controls allow the user to oper- consists of three basic components: the detector, electronic ate the instrument and visually (also sometimes aurally) be

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C-5 TABLE C-6 Most Likely RDD Radioisotopes and their Radiation Properties Radioisotope Half-Life Type of Radiation Maximum Energy of [physical form] [Curies per Emitted Radiation Emitted {body organ in which it accumulates} gram]1 (Mev) Cobalt-60 5.3 years Beta, gamma 0.3, 1.3 [solid metal] [1,130] {liver and body tissues} Iodine-125 60 days Beta, gamma 0.15, 0.04 [chemically reactive, soluble, low [17,400] melting and boiling point crystalline solid] {thyroid} Cesium-137 30.1 years Beta, gamma 0.5, 0.7 [solid soluble salt] [87] {muscles} Iridium-192 84 days Beta, gamma 0.8, 0.5 [solid silvery white metal] [9,170] Strontium-90 29.1 years Beta 0.5 [solid silvery metal] [141] {bones and teeth} Plutonium-238 88 years Alpha, beta, 5.5, 0.01, 0.002 [solid heavy metal] [17] gamma [liver and skeleton} Radium-226 1,600 years Alpha, beta, 4.8, 3.0, 2.0 [solid heavy metal] [0.988] gamma {bone and teeth} Americium-241 433 years Alpha, beta, 5.5, 0.05, 0.06 [solid heavy metal] [3.5] gamma {liver and skeleton} Curium-244 18 years Alpha, beta, 5.8, 0.09, 0.002, 2.5 [solid heavy metal] [80.9] gamma, neutrons {liver and skeleton} Californium-252 2.6 years Alpha, beta, 6.0, 0.04, 0.9, 2.0 [solid heavy metal ] [546] gamma, neutron {liver and skeleton} 1 = Indicates how much mass is needed for a given amount of radioactivity, for example one gram of Cobalt-60 has over 1,000 times the radioactivity of one gram of radium-226. [____] = highest radioactivity per unit of mass bold = highest energy gamma or neutron emitter; greatest external radiation hazard informed of the magnitude of the radiation dose rate at the radioisotopes. Good quality radiation detectors using either detector. the ionization chamber or Geiger-Muller tube are estimated to A general-purpose survey radiation detection meter, which cost between $400 and $1500 each. A number of manufac- can detect alpha, beta, and gamma radiation (all the radioiso- turers can offer such detectors including: Ludlums, Canberra, topes listed in Table A.3 emit alpha, beta, or gamma radia- BNFL, Laurus, Atlantic Nuclear, Cardinal Health (used to be tion) over a wide range of dose rates, is rugged, portable, and Victoreen), and Thermo-Eberline. easy to use is the optimum instrument for first responders to a transportation system threat, which may involve a RDD. This meter is not required to measure dose rates to a high C.5 EXAMPLES OF ANALYZED RDD degree of accuracy ( 2050% is acceptable) and will not INCIDENT EFFECTS identify the individual radioisotope(s), which are the source of radiation. These capabilities require more complex, expen- Figures C-1 and C-2 illustrate typical dispersion maps sive, cumbersome, and heavier instrumentation. Subsequent showing how the radioisotope concentration, contamination emergency responders from appropriate nuclear agencies will (and radiation dose rate) changes from the point of release out have this capability. The initial emergency responders only to different distances for an incident in Washington, D.C. and need to identify if radioactive material was released, the gen- New York City. Figure A-1 shows the plume of radioactive eral magnitude of the radiation dose field, and the physical lo- contamination from an RDD incident at the National Gallery cations of deposited radioactive contamination. of Art with a wind towards the southeast. Figure C-2 shows Analysis of the most likely RDD radioisotopes and their radioactive contamination plume from an RDD in downtown relevant properties, which are delineated in Table C-3, points Manhattan with a wind blowing towards the northeast. The to a "pancake-type" Geiger-Muller tube or an ionization boundary of each constant shade area represents a contour of chamber detector as the optimum meter to detect each of these constant radiation dose rate. Within the shaded area, the dose

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C-6 tamination with more air as compared to a lower turbulence. The time for radioactive material to reach a specific distance is directly related to wind speed. Both Figures C-1 and C-2 are examples of dispersion of fine solid particulate radioactive material in an outside and relatively open location. Release in an enclosed space such as a tunnel, subway station, aircraft, or other transportation vehicle would be subject to an entirely different behavior. Radioactive particulate distribution would be more concen- trated within the enclosed space or volume. In a tunnel or un- derground station, airflow and the movement of vehicles and humans would spread contamination. While moving, airflow out of any transportation vehicle (e.g., truck, train car, sub- Figure C-1. Washington D.C. hypothetical RDD way car, aircraft, etc.) would carry a stream of radioactive radiation dose rate and contamination. particles to the surrounding environment. rate and level of radioactive contamination is a value between C.6 HISTORICAL RADIOLOGICAL INCIDENTS the two contour boundary lines. INVOLVING TRANSPORTATION In each scenario, the direction of the oval or parabolic distri- SYSTEMS bution of radioactive material is following the wind direction and each release includes the energy of a small quantity of TNT In the approximately 100 years since the discovery and use with the radioisotope. The rate of dilution and spreading of a of radioactivity, numerous radiological incidents have oc- plume is controlled by the intensity of turbulence in the atmos- curred that resulted in unintended radiation doses to individu- phere. Turbulence increases with wind speed, traffic, and heat als and radioactive contamination. During the first 60 years of emitted from buildings. The turbulence has two different ef- the twentieth century, most incidents were due to a lack of fects on spreading radioactivity. The higher turbulence spreads knowledge of the biological limits of radiation or were associ- the contamination over a greater area, but also dilutes the con- ated with the research and development of nuclear technology for military applications. The most commonly known nuclear incidents in the area of civilian nuclear applications are the Chernobyl and Three Mile Island nuclear power plant acci- dents in 1986 and 1979, respectively. These events did not di- rectly involve a transportation system and emergency response was led and controlled by federal government agencies. In the U.S., about three million shipments of radioactive materials by highway, rail, air, and sea are made annually. No deaths or serious injuries have ever been attributed to radia- tion from these shipments. Since 1971, 45 million packages of radioactive material have been shipped and 3,453 have been involved in accidents, but only 197 of these resulted in enough damage to release any radioactivity. No radiation doses to the public or workers were serious enough to require medical care or violated government limits. Evaluation of his- torical data on radiological incidents was focused specifically on transportation related events with representative events presented in Table C-7. This table shows that very little radioactive material release Figure C-2. New York City or contamination has ever been released from civilian trans- hypothetical RDD radiation dose rate portation. Most civilian radioactive accidents have had no and contamination public or worker health effects.

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C-7 TABLE C-7 Historical Representative Transportation System Radiological Release Incidents Date Transport Incident Description Mode 1954 Sea Experimental navy nuclear submarine Seawolf was scuttled in 9,000 feet of water off the Delaware/Maryland coast with 33,000 Curies of radioactivity released; never recovered 1958 Highway Tank trailer with 1,500 gallons of liquid uranium solution overturned near Hanford, Washington when brakes failed on hill. Contaminated fluid was flushed into ditch and soil was shipped to a radioactive waste storage site. (Washington state) 1960 Truck Spent nuclear fuel cask leak onto trailer floor, contamination confined to vehicle 1963 Rail Spent nuclear fuel cask leak, contamination confined to cask and trailer 1964 Air (Space) U.S. nuclear powered navigation satellite burns in the atmosphere releasing 17,000 Curies of Plutonium-238 1966 Air B-52 bomber crashes with air tanker over Spain, two H-bombs fall near Palomares, their conventional explosive component detonates and spreads radioactive contamination. About ten pounds (about 278 Curies) of plutonium-239 spread over 650 acres. Over three months, 1,500 tons of topsoil and plants shipped to U.S. burial site. 800 U.S. military personnel and 900 Spanish civil guards used in cleanup. Total cleanup cost, not including lost aircraft, was $ 100 million 1971 Sea 500 gallons of radioactive water spilled in Thames River near New London, Connecticut while being transferred from nuclear submarine Dace to sub tender Fulton (Connecticut) 1971 Highway Tractor-trailer with 25-ton cask containing spent nuclear fuel overturned after swerving to avoid head-on collision. The trailer broke away and skidded into water filled ditch. No radioactive material was released. 1978 Air (Space) Russian Cosmos 954 nuclear powered satellite crashes into Canada's desolate unpopulated Northwest Territories spreading spent nuclear fuel radioactive contamination over 15,000 square miles. Fragment radiation dose from mrem/hr. to 100 rem/hr. Cleanup took three months and about $7Million (Canada) 1978 Sea 500 gallons of radioactive water released to Puget Sound, Washington when nuclear submarine Puffer accidentally opened valve (Washington state) 1987 Sea French Cargo Ship Mont Louis with 350 tons of uranium hexafluoride sunk in a collision with a car ferry 9 miles from the coast of Belgium in 49 feet of water. The 30 casks were recovered and only one was found to be leaking. 1997 Sea MSC Carla split in two in a storm. It carried 3 casks holding a total of 9 Curies of Cesium-137 as Cesium Chloride. It sunk in 9800 feet of water in North Atlantic North of Azores and no recovery was attempted. 1997 Rail Special train car with containers of Iridium-192 and Cobalt-60 collided with bulldozer, containers were broken and spread radioactive contamination (Russia) 1999 Highway Accident between 2 Trucks, both caught fire, one truck was carrying containers and syringes with radioactive material. All radioactive material was contained and accounted for with no highway contamination (Ohio) 2000 Air A package containing two 0.05 mCi Californium-252 sources was damaged by a fork lift truck during cargo handling at an airport terminal. Confinement was not breached. (U.K.) 2003 Rail Rail car carrying radioactive waste struck another rail car in the rail yard loosening cover of car, but no radioactive material was released (Maine)