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6 CHAPTER 2 TRANSPORTATION RESPONSE TO CBR EVENTS This section summarizes the key characteristics of CBR agents (i.e., incendiaries), which are most likely to cause threats (Sections 2.1, 2.2, and 2.3) and then compares these harm by burning and creating large amounts of heat (e.g., agents (Section 2.4). Sections 3.1, 3.2, and 3.3 focus on threat napalm and ethylene oxide). characteristics that will affect the selection of transportation This section discusses chemical fundamentals (2.1.1), response options and the development and implementation emergency response information needs (2.1.2), and interre- of a transportation response plan. Each of the threat-specific lationships among chemical threats and the transportation sections includes system (2.1.3). A fundamental description of the threat, Information needs for emergency response decision- 2.1.1 Fundamentals makers, and Discussion of transportation system vulnerabilities to Some background information can help in understanding the threat agent and consequence minimization. chemical threats. The fundamentals addressed in the subsec- tions below are Section 2.4 compares the general categories of CBR agents with respect to factors that decide their potential effects on the Basics, transportation system. Readers are encouraged to review Events, multiple information sources for better understanding of CBR Categories, threats. Because any given source may be very helpful and Doses, accurate in many aspects and still have some misleading pre- Detection, and sentation of factual details, it is important to recognize Decontamination the general level of information presented and that overall summaries often must generalize for the sake of simplicity More information on chemicals is readily available from and omit qualifying details (e.g., with respect to persistence many sources, including the Internet. Some of these sources in specific types of environments, lethality or contagiousness are listed in Appendix A. of particular strains, etc.). For another general source for an introduction to CBR threats is The National Academies Fact Sheets on Terrorist Attacks, available on line at Basics http://www.nae.edu/nae/pubundcom.nsf/weblinks/CGOZ- 642P3W?OpenDocument Thousands of different chemicals pose different threats to humans. Some basic concepts and associated terms used in evaluating a specific chemical toxin are as follows: 2.1 CHEMICAL THREATS Toxicity. This is a measure of the quantity of a sub- Familiarity with the basic types of chemicals that may stance required to get a harmful effect. Depending pose threats can aid in developing appropriate emergency on the type of harmful effects cause by the chemical, response plans. The effects of toxic chemical releases range a highly toxic chemical may or may not be likely to from irritations to fatality. The chemical agents addressed in cause death. this report are those that react chemically with the cells of Lethality. This refers to how much of a substance is the human body to cause adverse effects. Types of chemi- needed to cause death. Not all chemical weapons are de- cals not included in this report are those that pose their great- signed to maximize lethality (e.g., riot-control agents, est threat by displacing substantial amounts of ambient which are designed to incapacitate, but not kill, the target). oxygen during a large release, thereby causing asphyxiation Exposure route. Exposure routes are the pathways by (e.g., methane, nitrogen, carbon dioxide), and flammable which a chemical may enter the body. The most common

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7 exposure route for both chemical weapons and an indus- event, such as occurred in Bhopal, India, a radius of trial chemical release is inhalation, followed by skin tens of miles and the health of many thousands of absorption. The final exposure route, ingestion, may people may be threatened. occur with contamination of food and water supplies and Chemical transportation incident--refers to an acci- to a much lesser extent with inhalation of particles. dental or deliberate release of chemicals that are in Speed of action. This refers to the delay between expo- transport. Large quantities of chemicals are trans- sure to a toxin and the beginning of symptoms, which ported in special containers, which, if breached, can varies from split-seconds to hours. result in a significant chemical release. This may Persistence. This refers to the length of time the chem- occur inadvertently, such as in the case of the recent ical remains toxic after release. Loss of toxicity may be (February 2004) runaway train in Iran, which de- caused by dilution, as when a gas is dissipated by the railed and released sulfur, petrol, and fertilizer wind, or chemical breakdown from various chemical before an explosion that killed more than 300 on- reactions that may occur with water, oxygen, and light. lookers. In a deliberate release, a vehicle or vessel The military defines a chemical as non-persistent if it may be attacked or hijacked and driven to a densely is likely to evaporate or break down from a ground populated area before the chemical release to maxi- surface in less than 24 hours at temperatures of 60 to mize injury and destruction. 80 F. Most if not all, commercial chemicals carried in Chemical Weapons Event. Refers to the use of chemi- bulk (e.g., chlorine, ammonia, and hydrogen fluoride) cal weapons agents that may have been produced by a are non-persistent. government or by terrorist organizations. Precursors for Dose. A dose is the amount of a chemical taken into the chemical weapons may be obtained legally or ille- the body and depends on the chemical concentration, gally. Large quantities of chemical weapons are more the duration of exposure, and the route of exposure. The difficult to obtain than industrial chemicals, thus re- quantity of a chemical needed for a dose to yield harm- leases of chemical weapons in crowded enclosed spaces ful effects depends on the chemical toxicity and the ex- (e.g., subway or airport), where a small amount may be posure route. effective is a more likely terrorist scenario than an open- air release. Events In general, a serious chemical event may result in hundreds to a few thousand casualties and in thousands of permanent From an emergency response perspective, understanding injuries. As large as the magnitude of these consequences where, what type, and how much chemical contamination seems, it is not as great as could occur from a serious radio- has been released are the key issues for decision-making in logical or biological event, which are addressed in other the event of a chemical threat. The cause of the chemical sections of this report. release is, in many cases, likely to be a secondary issue for response management unless it suggests an increased possi- bility of a second release. However, recognition of the types Categories of chemical events that may occur can assist in both assess- ing regional vulnerabilities and in developing scenarios for Many methods exist for grouping or categorizing the emergency training and exercises. Two basic types of chem- many thousands of chemicals available. OSHA and DOT ical releases are described below. use a similar classification of chemicals based on the type of physical hazard posed (e.g., explosives, flammable liquids, Chemical Infrastructure Event. Chemicals may be re- and corrosives).1 The OSHA/DOT classification system leased from any of the thousands of facilities in the typically is used to describe chemicals involved in chemical United States that produce, handle, use, and store chem- infrastructure incidents, either at a chemical facility or dur- icals, or chemicals in transport between these facilities. ing transport. However, when chemicals are intentionally Two types of release events that have received substan- used to threaten people, they are referred to as chemical tial attention and response planning are weapons and spoken of in terms of their military classifica- Chemical plant incident--involves the accidental or tion. The military classification system is based on the deliberate release of dangerous levels of chemicals human symptoms the agent causes (e.g., choking, blister, from one or more of the 66,000 chemical facilities in and nerve). Many of these weapons classes were first used the United States. The FBI has long warned that at- in World War I. The most common classes of chemical tacks on an industrial facility may come from a local or disgruntled employee, just as the 1984 Bhopal in- 1 The Department of Transportation Emergency Response Guidebook, 2004, de- cident appears to have been a result of human error scribes this classification system and can be viewed or downloaded from links provided or sabotage by a demoted employee. In an extreme at http://hazmat.dot.gov/pubs/erg/gydebook.htm

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8 weapons that have proliferated since WWI are described than blister agents, but have been produced and used by below: terrorists (i.e., sarin was used in 1995 by the Aum Shin- rikyo cult in Tokyo). Some nerve agents have been used Choking agents. Inhalation is the typical exposure route along with blister agents for a broader scope of effects. for choking agents, also called "respiratory" or pul- Blood agents. These toxins typically are taken into the monary" agents. They are lung irritants that cause fluid body by inhalation and act by blocking oxygen use or build-up in the lungs, which can result in suffocation as uptake from the blood, thereby causing suffocation. much as 24 hours after exposure. Although choking Hence, blood agents are also called "chemical as- agents are no longer common as military weapons, phyxiants." Some of the more common blood agents many choking agents are common industrial chemicals, are hydrogen cyanide (the active ingredient in Zyklon and their release from an industrial facility or during B), hydrogen sulfide, and cyanogen chloride. These bulk transport can have devastating effects. Histori- agents are highly volatile and difficult to store and cally, chlorine and phosgene have been the most used have a low persistency on release. However, they are chemical weapon choking agents and are currently also very lethal and act very quickly. Agents such as mass-produced by the chemical industry. Some chok- hydrogen cyanide are easily produced from common ing agents are gases at standard temperature and pres- industrial chemicals and therefore may attract terrorist sures (e.g., chlorine and phosgene); others are liquids interest. that are most dangerous as aerosols (e.g., diphosgene). Riot-control agents. These include pepper sprays and Choking agents generally dissipate relatively easily tear gases (e.g., CS and CN, both of which are actu- under many open-air circumstances so typically are not ally solids at standard temperature and pressure). persistent. They irritate the eyes, nose, and mouth, initially mim- Blister agents. These agents cause serious skin and eye icking other chemical weapons agents. CS is favored irritation. Blister agents, also referred to as "vesicants," for large-scale riot control because of its low toxicity are the most widely used and stockpiled chemical and short-term effects (5 to 15 minutes). Although weapon. Although blister agents can cause death, they they are not generally lethal unless ingested in high are not considered very lethal. They are used primarily doses, riot control agents can cause extreme discom- to cause substantial distress, put demands on the med- fort and panic, which can lead to lethal events. Fur- ical system, and incite general public fear. Blister agents thermore, in enclosed areas, fine particles from some include sulfur mustard, nitrogen mustards (e.g., HN-3), riot control agents may facilitate explosions similar to and Lewisite. They are low-cost and relatively easy to grain elevator explosions. mass produce. Although eye irritation often occurs within minutes, the development of noticeable skin irri- Other, less common chemical weapons classes include tation varies from seconds for Lewisite, to hours for vomit agents and incapacitants (i.e., psychoactive chemicals). mustard agents. Many blister agents will persist on Non-toxic chemical agents, such as obnoxious odorants, can surfaces for days in the summer and, depending on the be used to harass or mask other toxic compounds. In recent temperature, may persist for weeks in the winter. In years there have been more than one hundred cases of "nox- soils, persistence may be longer. Blister agents can seep ious chemical vandalism" on abortion clinics throughout the through fabric, rubber, and leather, so first-responders United States. The chemical agent in these events was butyric and decontamination crews require special protective acid, which produces a rancid butter odor, can irritate skin and clothing. eyes, and requires much effort to remove the odor. With the Nerve agents. These organophosphate chemicals are classification of these cases as vandalism, terrorism experts liquids at standard temperatures and pressure. Exposure generally believe that nerve and blister agents are the most routes are inhalation and skin contact, depending on the likely chemical weapons to be used by government-defined dispersion method (i.e., size of aerosol droplets), and terrorists. their rate of evaporation after settling. Nerve agents In addition to chemical weapons agents, numerous indus- paralyze the respiratory muscles and can cause death trial chemicals at both fixed sites and during transport may within a few minutes when inhaled, whereas a drop on be attractive to terrorists. Based on available sources, FBI in- unprotected skin may take several hours to produce se- vestigations, product availability, and the complexity of vere symptoms and possible death. Some of the more manufacture and development, the FBI has developed a list common chemical weapon nerve agents are sarin, of industrial chemicals potentially attractive to terrorists tabun, soman, and VX. They vary in persistence from (Table 2-1). Appendix A contains a list of other organiza- a few hours for sarin to days or weeks on surfaces tions that have similar lists of chemicals of concern and a (i.e., potential skin exposure) for agents such as VX. summary table of specific characteristics of several potential Nerve agents require more sophistication to produce chemical agents

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9 TABLE 2-1 FBI Community Outreach Program List of Potentially Attractive Chemicals for Terrorist and Criminal Activity Ammonia Arsenic Arsine Boron Trichloride Boron Trifluoride Butyric Acid Carbon Disulfide Chlorine Chloroacetone Cyanides Diborane Dimethyl Sulfate Dimethyl Sulfoxide (DMSO) Ethylene Oxide Fluorine Formaldehyde Hydrogen Bromide Hydrogen Chloride Hydrogen Fluoride Hydrogen Sulfide Mercury Methyl Phosphonyl Dichloride N,N'-Dicyclohexyl carbo-dimide (DCCDI) N,N'-Diisopropylcarbo-diimide (DICDI) N,N'-Dimethylamino Phos- Nitric Acid Phosphine Phoryl Dichloride Phosphorus Trichloride Sodium Azide Sodium Fluoroacetate Sulfur Dioxide Sulfuric Acid Thallium Thiodiglycol Thionyl Chloride Tributylamine Tungsten Hexafluoride 2-(Diisopropylamino) ethane thiol 2-(Diisopropylamino) ethanol Reproduced from the FBI Community Outreach Program for Manufacturers and Suppliers of Chemical and Biological Agents, Materials, and Equipment (http://www.aiche.org/ccps/pdf/fbi_wmd.pdf). This list is by no means complete. Other lists of potentially attractive chemicals are provided in Appendix A. Doses and Concentrations of Concern or 0 percent). Concentrations of concern are established by government agencies (e.g., OSHA, DOE, or EPA) and in- The specific dose of a chemical that is received is not easily dustry associations on the basis of multiple studies. In measured, unless the chemical is given in a carefully measured a chemical release event, concentrations that cause long- way. This is because the amount of a chemical taken into the lasting health effects from short-term exposures are a body can vary among individuals. For example, the dose re- primary reference for response management. Table 2-2 ceived of a blister agent may vary with the type of clothing an displays concentrations as parts per million (ppm) of several individual is wearing. Therefore, exposure to chemicals in the chemicals. The concentrations shown are Acute Exposure environment is often discussed in terms of exposure concen- Guideline Limits (AEGLs) established by EPA. AEGL-2 trations rather than doses. concentrations are airborne concentrations above which the Chemical concentrations of concern vary depending on general population could experience irreversible or long- the situation being addressed. For example, in an office lasting serious health effects, or an impaired ability to es- workplace, the amount of ozone that causes 50 percent of cape. AEGL-3 concentrations are airborne concentrations the employees to have burning eyes for several hours above which the general population could experience life- every workday is a serious issue. However, in a chemical threatening health effects or death. The smaller the AEGL, weapons event, this same effect is not generally consid- the smaller the amount of the material that needs to be re- ered serious (although the event may be considered seri- leased to cause dangerous health effects to people within a ous as an indication of possible future, more harmful given area. Appendix A describes other chemical concen- events). The many different concentrations of concern for trations of concern. chemicals reflect the differences in levels of effect that are a concern. Concentrations of concern are based on a specific effect Chemical Detection (e.g., discomfort, serious injury, or death), within a specific time (e.g., immediate, 10 minutes, 96 hours), in a specific Identification of chemicals involved in chemical infra- percentage of the population (e.g., 1 percent, 10 percent, structure incidents can often be determined from OSHA- and TABLE 2-2 Examples of Acute Exposure Guidelines for Inhalation Chemical AEGL-2 (ppm) AEGL-3 (ppm) 10 min 1 hr 8 hr 10 min 1 hr 8 hr Ammonia 270 110 110 2,700 1,100 390 Chlorine 2.8 2.0 0.71 50 20 7.1 Hydrogen Cyanide 17 7.1 2.5 27 15 6.6 Sarin 0.015 0.006 0.002 0.064 0.022 0.009 Sulfur Mustard 0.09 0.02 0.002 0.59 0.32 0.04 (Source: EPA's National Advisory Council/AEGLs website at http://www.epa.gov/oppt/aegl/chemlist.htm)

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10 DOT-required labeling and tracking. In a chemical facility Chemical Decontamination incident, first responders may be able to identify the chemi- cal based on community preplanning lists of hazardous The need for decontamination of chemical agents depends chemicals at specific locations. In addition, emergency on their concentration and persistence. There is no generally personnel should be alert to other obvious locations in their accepted guide on large-scale chemical decontamination communities that use hazardous materials, such as laborato- methods. Thus, when persistence is long enough to consider ries, factories, farm and paint supply outlets, and construc- active decontamination, controversy is likely. The trade-off tion sites. between passive decontamination (i.e., isolating the con- In a chemical transportation incident, cargo chemical taminated area and allowing the contaminant to degrade identity can be determined from or become diluted naturally) and active decontamination (i.e., taking action to degrade or dilute the contaminant to Container Shape. DOT regulations dictate certain shapes safe levels) will be affected by the location and size of the for transport of hazardous materials. contaminated area, the affected population and economy, Markings. Transportation vehicles must use DOT mark- and the persistence of the chemical agent and the hazards as- ings, including identification (ID) numbers, located on sociated with decontaminating agents (e.g., chlorine). both ends and sides of all cargo tanks, portable tanks, Blood agents such as hydrogen cyanide, arsine, and cy- rail tank cars, and other small packages that carry haz- anogen chloride are chemical asphyxiants that evaporate ardous materials. rapidly in the environment, generally precluding the need for Placards and Labels. These convey hazard class infor- decontamination actions. In enclosed conditions where de- mation by use of colors and symbols, and either hazard contamination may be needed, both respiratory support and class wording or four-digit identification numbers. Plac- protective clothing are needed, because these agents may ards are used when hazardous materials are in bulk such also be absorbed through the skin and eyes. as in cargo tanks; labels designate hazardous materials In contrast, blister agents are very persistent at cold tem- on small packages. peratures. However, at warmer temperatures, evaporation Shipping Papers. These provide the same information rates increase causing higher vapor concentrations that pre- as on placards and labels. Such papers also provide to sent inhalation as well as skin absorption hazards. Many of the shipper name, quantity of material, and general these agents are inactivated gradually by sunlight, increasing emergency response instruction. Shipping papers must the rate of their degradation in outdoor versus indoor envi- accompany all hazardous material shipments. ronments. There are exceptions however, Lewisite is both Senses. Odor, vapor clouds, dead animals or dead fish, stable below about 120 oF and is not inactivated by sunlight. fire, and irritation to skin or eyes can signal the presence The primary mode for active decontamination of blister of hazardous materials. agents has been copious amounts of water with a 0.5% hypochlorite solution (1 part bleach, 9 parts water). Protective After a chemical has been identified, information on how to respiratory support and clothing must be worn by trained per- respond can be found in various references, such as Material sonnel. Phosgene oxime is unique among the blister agents Safety Data Sheets (MSDS), the DOT Emergency Response in that it may be chemically inactivated using an alkali. Guidebook, and the CHEMical TRansportation Emergency Nerve agents such as sarin, soban, and tabun evaporate and Center (CHEMTREC) web page (http://www.chemtrec.org/ loose their toxicity within minutes to days, depending on tem- Chemtrec/), in addition to the shipping papers. peratures. The need for active decontamination is increased for Thus, there are several sources of on-scene information nerve agents that are slower to evaporate (i.e., soman, GF, and for chemical events involving a chemical facility or chemi- VX). For active decontamination of nerve agents, water has cal transportation. In contrast, none of this information been used. Nerve agents are organophosphates, which is the would be available during a chemical weapons event. same chemical family as many common pesticides (e.g., chlor- Regional HazMat teams should be equipped with Technical pyrifos, diazinon, disulfoton, malathion, sevin, etc), thus water Operations Modules, or science and control units that con- run-off containing these agents may pose hazards for both en- tain chemical detection equipment such as chemical detec- vironmental and human health. tor system kits; programmable chemical agent detectors; Both nerve and blister agents may be thickened into an oily and M256A1 Chemical Agent Detector Kits. HazMat teams liquid that can remain on surfaces as a persistent hazard. When may also have multigas meters, organic vapor analyzers, and the agents are thickened, a soap and bleach solution is used. In gas chromatograph/mass spectrometers. If the HazMat team both cases, protective clothing and respiratory protection are cannot identify the chemical in question, the incident com- needed during the clean-up. mander probably will be able to call on the services of local The use of large quantities of chlorine (i.e., bleach), in laboratories (e.g., in universities) for assistance. These var- particular, may be subject to EPA and similar state require- ious detectors can also be used during chemical facility and ments. These requirements may include containment of run- chemical transportation incidents. off, measurement of water quality, and possible sustained