Nuclear Emergency Operations 101

Walmer E. Strope

The terrible terrorist attack of September 11 has aroused concern that such fanatics would not hesitate to cause a nuclear explosion in America if and when they were able to do so. What should be done to prepare to deal with the consequences of a nuclear attack so as to save as many lives as possible?

The Defense Civil Preparedness Agency (DCPA) developed a concept of nuclear emergency operations during the Cold War years. When DCPA was superceded by the Federal Emergency Management Agency (FEMA) in 1979, emphasis was placed on preparations to deal with natural disasters rather than nuclear attack. For nearly two decades, nuclear attack preparedness has not been included in emergency management training, exercises, or planning. The purpose of this paper is to summarize the "lost" conceptual framework of nuclear emergency operations planning. FEMA should adopt this concept and employ it in planning and training for a possible terrorist nuclear attack.

Nature of the Problem: A terrorist nuclear bomb and even a nuclear-tipped ballistic missile most likely would be detonated on or near the ground level, causing a crater and not only blast destruction and fires but also radioactive fallout over a widespread area. It is important to recognize that the fallout from a surface burst will extend well beyond the region of damage and fires in the downwind direction, threatening death and injury to large numbers of people not otherwise at hazard.

The terrorist nuclear explosion will occur with little or no warning. People in the damage area will suffer injury or death depending on their location and immediate surroundings. Survivors, injured and uninjured, will be found even close to the crater (there were survivors at ground zero at Hiroshima), increasing in numbers with distance from the crater. Radioactive fallout from the explosion takes time to arrive at ground level and the explosion itself is warning to take cover. Moreover, radiation exposure takes time to accumulate to injurious or lethal amounts, allowing for lifesaving measures to take place. On the other hand, radiation itself is not detectable by the human senses. Detecting devices (radiacs) or very accurate predictions are needed to aid emergency operations. (A more detailed discussion of nuclear weapon effects will be found in FEMA H-21, "Nuclear Attack Environment Handbook.")

Basic Operating Situations: A central element of the concept of operations is the basic operating situation (BOS.) Emergency operations involve actions to counter imminent threats to life and property and to maintain or restore essential services and facilities. These actions are firefighting, rescue, and medical aid, assisted by law enforcement and public works. The need for these actions and the conditions under which the actions must take place depend on the basic operating situation.  A schematic view of the overall situation following a nuclear explosion is shown here:




Text Box: 9

Text Box: 1

Text Box: 8


Text Box: 7

Text Box: 3

Text Box: 5

Text Box: 6

Text Box: 4







The small star represents the crater made by the explosion. The outer circle represents the edge of the damage area; that is, the beginning of light damage. The inner circle represents the zone of fires or heavy debris that bar the use of wheeled vehicles. The long ovals represent levels of fallout radiation; the outer one representing the edge of the fallout area, defined as a dose-rate of 0.5 roentgens per hour (0.5 r/hr.) The inner oval represents the area 100 times more severe or 50 r/hr.

There are nine basic operating situations. BOS 1 is the situation in the area suffering neither physical damage nor fallout. People without emergency duties should be directed to best available shelter and emergency services should go to assist those in affected areas. BOS 2 occurs in the undamaged fallout area when dose-rates are less than 50 r/hr. People in poor or inadequate shelter can be evacuated but emergency workers are limited to only a few hours of exposure to radiation to avoid radiation sickness. BOS 3 is the "pin-down" situation in best available shelter since safe time in the open is too limited to be useful.

BOS 4 occurs in the light to moderate damage area with no fallout. This generally is located in the upwind part of the damage area for a surface burst. Classical search, rescue and medical aid actions are appropriate. BOS 5 is similar to BOS 4 but the existence of fallout radiation limits the effectiveness of rescue and medical aid actions. BOS 6 couples moderate damage with high levels of fallout radiation. Use of best available shelter is required until radiological decay permits outside actions.

BOS 7 occurs in the heavily damaged area near the crater upwind of the fallout plume. This situation may not exist for some wind conditions following a surface burst. Rescue actions are limited until debris clearance can be accomplished. BOS 8 is the more likely situation in the heavily damaged area following a surface burst in that fallout radiation up to 50 r/hr will be present, further restricting emergency operations. BOS 9 occurs directly downwind in the heavily damaged area, effectively curtailing emergency operations.

The nine Basic Operating Situations can be summarized as shown here:








.5-50 r/hr




<0.5 r/hr

Heavy Damage

Light Damage



Damage Assessment and Fallout Warnings: All local emergency operating centers (EOCs) and emergency forces are in BOS 1 prior to a nuclear explosion. They should be instructed to report any BOS change when it occurs. These BOS changes are the basis for rapid damage assessment and fallout prediction. In the 1970s DCPA conducted a test exercise in Florida in cooperation with the State. All local county and municipal EOCs participated and were trained in the BOS concept. None, including the Florida State EOC, knew anything about the nature of the simulated attack. Each only learned when "trusted agents" gave them a slip of paper with an event description that would put them in a different BOS. The receipt of BOS changes enabled the State EOC to acquire and understand the developing attack effects in real time, to advise localities on proper actions and to warn those downwind of impending fallout and the time of arrival.

Use of BOS changes is a major improvement over the old procedure of making fallout predictions based on partial burst information and wind data that is often nearly a day old. (The Marshallese natives were injured by fallout in 1954 because the best meteorologists in the business couldn’t make an accurate prediction.) BOS changes are a reflection of the actual situation as it develops. Therefore, the population can be instructed both in advance and at the time to take shelter if a nuclear explosion occurs within 100 miles because localities in BOS 1 can be released to engage in mutual aid at an early time. Time is of the essence in nuclear emergency operations. Measures tardily undertaken are likely to be ineffective. Rapid assessment of BOS changes permits effective action. Professional radiological defense officers (RDOs) are not needed to make a timely assessment. That was demonstrated in the Florida experiment.

Use of BOS in planning and training: The nine Basic Operating Situations form a framework for planning automatic and contingent response at the local level. DCPA developed a generic operations plan of this type that was tested but never deployed. The plan is keyed to observable "triggering events," for each of which a set of actions is prescribed. The actions are of two kinds: automatic and conditional. The conditional actions are of the form, "If so and so has occurred, then do such and such." This permits BOS changes and unforeseen situations to be accommodated. By use of scenarios of triggering events, desktop exercises can be a useful form of training.

The Basic Operating Situations also form a framework for intensive training sessions in which details of planned actions are explored and the consequences of inaction are exhibited. Professional training of radiological defense officers and medical and rescue teams should use this framework.

Organizational basis: The level of operational control that would be dealing directly with the accomplishment of nuclear emergency operations is called an "operating zone." The essential feature of an operating zone is that it must contain internally enough resources to make independent emergency operations feasible. For practical purposes, any entity that has its own fire service can and should be an operating zone. Most operating zones will be civil jurisdictions: cities, towns, and counties. In large cities and counties, each fire district should be organized as an operating zone. In addition, military bases that provide their own fire service should be operating zones. Many state-owned facilities, such as universities, hospitals and prisons, will qualify if they have a sufficient population and provide their own fire and police protection, as will private universities, large industrial plants, and major tourist attractions.

The operating zone basis must be complete: all of the area must be covered and any part must be assigned to one and only one zone. A typical county (or county-equivalent) may be regarded as a zone within which are other zones, such as municipalities, military bases and other large facilities. This form of cellular organization is advantageous in that few zones will be so large that they might experience several BOS simultaneously as the consequence of a nuclear explosion. So long as all zones are using the same concept of operations, confusion and operations at cross purposes will be avoided.

The lines of communication and authority from civil operating zones to the State EOC should be developed in an unambiguous way, as is the case for military operating zones through the military chain of command. Zones based on public and private facilities should generally report to the civil jurisdiction within which they are located.

Internal Zone Organization: Each zone must develop two capabilities: (1) to assign its population to the best available shelter and care for them there, and (2) to organize the emergency services to perform emergency operations. It is the latter capability that is emphasized here. The most simple zonal emergency organization would consist of a direction and control (D&C) element and five operating services (police, fire, medical, shelter and resource.) The precise organization should conform to local practice. For example, rescue units are often found in the fire, medical or resource (public works) services or all three. The emergency services must be trained to perform their tasks not only within the zone but also in neighboring zones as mutual aid forces. Thus, a major portion of the services must be mobile. In addition to their normal equipment, D&C and mutual aid columns must be provided with CDV-715 radiacs or equivalent.

Summary of the Concept: When a nuclear explosion occurs, zone units outside the affected area move toward the damaged area until they encounter light damage or fallout radiation. At that point, they report a BOS change and set up a control point (road block, medical treatment facility, survivor reception center, etc.) Since units are converging from all directions, the set of control points forms a "support perimeter."

Fire and rescue elements continue into the affected area until stopped by a high radiation level, widespread fires or debris that blocks the movement of wheeled vehicles. These severe weapon effects define the "action perimeter." Initially, firefighting and rescue of survivors takes place mainly between the two perimeters. This operating concept has been called "a two-perimeter defense system based on a cellular organization."

In this summary, the actions of units located outside the affected area have been cited. But some of the operating zones will find themselves in the damaged or fallout area. Those near the edge of the affected area can set up a control point very quickly, then be augmented by mutual aid units as they arrive. Those zones further in may be fighting fires and rescuing survivors, including their own people, when more distant help arrives.

Recommendations: FEMA, which has responsibility for consequence management, should search out the DCPA documentation for the BOS concept, update the planning and training materials as necessary, and promulgate them at the earliest opportunity. After all, the Federal Government paid for this development and should deploy it now that it is needed.

In accordance with the concept, FEMA should move immediately to expand the number of operating zones beyond those represented by political subdivisions of the States. Exercises should be undertaken that require joint operation among counties, cities, towns, military bases, other federal and state facilities and private institutions and industrial plants.

Since a surface nuclear explosion is the most likely, FEMA should move to distribute those radiation rate meters and dosimeters it has in storage and to acquire the additional instruments necessary to allow operations in fallout areas and should provide these to local operating zones.