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Bomb and Physical Security Planning

From Department of the Treasury Bureau of Alcohol, Tobacco and Firearms (ATF P75550.2)

Bombing and the threat of being bombed are harsh realities in today's world. The public is becoming more aware of those incidents of violence that are perpetrated by vicious, nefarious segments of our society through the illegal use of explosives. Law enforcement agencies are charged with providing protection for life and property, but law enforcement alone cannot be held responsible. Every citizen must do his or her part to ensure a safe environment.


This pamphlet is designed to help both the public and private sectors prepare for the potential threat of explosives-related violence. While the ideas set forth herein are applicable in most cases, they are intended only as a guide. The information provided is compiled from a wide range of sources, including the actual experiences of special agents of the Bureau of Alcohol, Tobacco and Firearms (ATF)


If there is one point that cannot be overemphasized, it is the value of being prepared. Do not allow a bomb incident to catch you by surprise. By developing a bomb incident plan and considering possible bomb incidents in your physical security plan, you can reduce the potential for personal injury and property damage.


In making this pamphlet available to you, we hope to help you better prepare to deal with bomb threats and the illegal use of explosives.




Bombs can be constructed to look like almost anything and can be placed or delivered in any number of ways. The probability of finding a bomb that looks like the stereotypical bomb is almost nonexistent. The only common denominator that exists among bombs is that they are designed or intended to explode.


Most bombs are homemade and are limited in their design only by the imagination of, and resources available to, the bomber. Remember, when searching for a bomb, suspect anything that looks unusual. Let the trained bomb technician determine what is or is not a bomb.


Bomb Threats


Bomb threats are delivered in a variety of ways. The majority of threats are called in to the target. Occasionally these calls are through a third party. Sometimes a threat is communicated in writing or by a recording.


Two logical explanations for reporting a bomb threat are:


1. The caller has definite knowledge or believes that an explosive or incendiary bomb has been or will be placed and he/she wants to minimize personal injury or property damage. The caller may be the person who placed the device or someone who has become aware of such information.


2. The caller wants to create an atmosphere of anxiety and panic which will, in turn, result in a disruption of the normal activities at the facility where the device is purportedly placed.


Whatever the reason for the report, there will certainly be a reaction to it. Through proper planning, the wide variety of potentially uncontrollable reactions can be greatly reduced.


Why Prepare?


If you accept the two aforementioned explanations for reporting that a bomb is about to go off, you can better prepare to foil the bomber or threat maker.


Through proper preparation, you can reduce the accessibility of your business or building and identify those areas that can be "hardened" against the potential bomber. This will limit the amount of time lost to searching, if you determine a search is necessary. If a bomb incident occurs, proper planning will instill confidence in the leadership, reinforce the notion that those in charge do care; and reduce the potential for personal injury and property loss.


Proper planning can also reduce the threat of panic, the most contagious of all human emotions. Panic is sudden, excessive, unreasoning, infectious terror. Once a state of panic has been reached, the potential for injury and property damage is greatly increased. In the context of a bomb threat, panic is the ultimate achievement of the caller.


Be prepared! There is no excuse for not taking every step necessary to meet the threat.


How to Prepare


In preparing to cope with a bomb incident, it is necessary to develop two separate but interdependent plans, namely a physical security plan and a bomb incident plan.


Physical security provides for the protection of property, personnel, facilities, and material against unauthorized entry, trespass, damage, sabotage, or other illegal or criminal acts. The physical security plan deals with prevention and control of access to the building. In most instances, some form of physical security may be already in existence, although not necessarily intended to prevent a bomb attack.


The bomb incident plan provides detailed procedures to be implemented when a bombing attack is executed or threatened. In planning for the bomb incident, a definite chain of command or line of authority must be established Only by using an established organization and procedures can the bomb incident be handled with the least risk to all concerned. A clearly defined line of authority will instill confidence and avoid panic.


Establishing a chain of command is easy if there is a simple office structure, one business, one building. However, if a complex situation exists, a multi-occupant building for example, a representative from each occupant entity should attend the planning conference. A leader should be appointed and a clear line of succession delineated. This chain of command should be printed and circulated to all concerned parties.


In planning, you should designate a command center to be located in the switchboard room or other focal point of telephone or radio communications. The management personnel assigned to operate the center should have the authority to decide whatever action should be taken during the threat. Only those with assigned duties should be permitted in the center. Make some provision for alternates in the event someone is absent when a threat is received. Obtain an updated blueprint or floor plan of your building and maintain it in the command center.


Contact the police department, fire department, or local government agencies to determine if any assistance is available to you for developing your physical security plan or bomb incident plan. If possible, have police and/or fire department representatives and members of your staff inspect the building for areas where explosives are likely to be concealed. (Make a checklist of these areas for inclusion in command center materials.) Determine whether there is a bomb disposal unit available, how to contact the unit, and under what conditions it is activated. In developing your bomb incident plan, you must also ascertain whether the bomb disposal unit, in addition to disarming and removing the explosives, will assist in searching the building in the event of a threat.


Training is essential to deal properly with a bomb threat incident. Instruct all personnel, especially those at the telephone switchboard, in what to do if a bomb threat is received. Be absolutely certain that all personnel assigned to the command center are aware of their duties. The positive aspects of planning will be lost if the leadership is not apparent. It is also very important to organize and train an evacuation unit which will be responsive to the command center and has a clear understanding of the importance of its role.


We have suggested that the command center be located near the switchboard or focal point of communications. It is critical that lines of communication be established between the command center and the search or evacuation teams- The center must have the flexibility to keep up with the search team progress. In a large facility, if the teams go beyond the communications network, the command center must have the mobility to maintain contact and track search or evacuation efforts.


Security Against Bomb Incidents


We mentioned earlier that, in dealing with bomb incidents or potential bomb incidents, two interrelated plans must be developed, the bomb incident plan and the physical security plan. Heretofore, we have primarily addressed the bomb incident plan. Now, before continuing with that plan, we will discuss security measures as they apply to "hardening" against the bomb attack.


Most commercial structures and individual residences already have some security in place, planned or unplanned, realized or not. Locks on windows and doors, outside lights, etc., are all designed and installed to contribute toward the security of a facility and the protection of its occupants.


In considering measures to increase security for your building or office, it is highly recommended that you contact your local police department for guidance regarding a specific plan for your facility. There is no single security plan that is adaptable to all situations. The following recommendations are offered because they may contribute to reducing your vulnerability to bomb attacks.


The exterior configuration of a building or facility is very important. Unfortunately, in most instances, the architect has given little or no consideration to security, particularly toward thwarting or discouraging a bomb attack. However, by the addition of fencing and lighting, and by controlling access, the vulnerability of a facility to a bomb attack can be reduced significantly.


Bombs being delivered by car or left in a car are a grave reality. Parking should be restricted, if possible, to 300 feet from your building or any building in a complex. If restricted parking is not feasible, properly identified employee vehicles should be parked closest to your facility and visitor vehicles parked at a distance.


Heavy shrubs and vines should be kept close to the ground to reduce their potential to conceal criminals or bombs. Window boxes and planters are perfect receptacles for the bomber. Unless there is an absolute requirement for such ornamentation, window boxes and planters are better removed. If they must remain, a security patrol should be employed to check them regularly.


A highly visible security patrol can be a significant deterrent. Even if this ''patrol'' is only one security guard/night guard, he/she is optimally utilized outside the building. If an interior guard is utilized, consider the installation of closed-circuit television cameras that cover exterior building perimeters.


Have an adequate burglar alarm system installed by a reputable company that can service and properly maintain the equipment. Post signs indicating that such a system is in place.


Entrance/exit doors with hinges and hinge pins on the inside to prevent removal should be installed. Solid wood or sheet metal faced doors provide extra integrity that a hollow-core wooden door cannot provide. A steel door frame that properly fits the door is as important as the construction of the door.


The ideal security situation is a building with no windows. However, bars, grates, heavy mesh screens, or steel shutters over windows offer good protection from otherwise unwanted entry. It is important that the openings in the protective coverings are not too large. Otherwise, a bomb may be introduced into the building while the bomber remains outside. Floor vents, transoms, and skylights should also be covered. Please note that fire safety considerations preclude the use of certain window coverings. Municipal ordinances should be researched and safety considered before any of these renovations are undertaken.


Controls should be established for positively identifying personnel who are authorized access to critical areas and for denying access to unauthorized personnel. These controls should extend to the inspection of all packages and materials being taken into critical areas.


Security and maintenance personnel should be alert for people who act in a suspicious manner, as well as objects, items, or parcels which look out of place or suspicious. Surveillance should be established to include potential hiding places (e.g., stairwells, rest rooms, and any vacant office space) for unwanted individuals.


Doors or access ways to such areas as boiler rooms, mail rooms, computer areas, switchboards, and elevator control rooms should remain locked when not in use. It is important to establish a procedure for the accountability of keys. If keys cannot be accounted for, locks should be changed.


Good housekeeping is also vital. Trash or dumpsite areas should remain free of debris. A bomb or device can easily be concealed in the trash. Combustible materials should be properly disposed of, or protected if further use is anticipated.


Install detection devices at all entrances and closed-circuit television in those areas previously identified as likely places where a bomb may be placed. This, coupled with the posting of signs indicating such measures are in place, is a good deterrent.


We in ATF recognize the necessity for businesses to maintain good public relations. Corporate responsibility, however, also encompasses the safety and protection of the public. The threatened use of explosives necessitates that in the interest of safety and security, some inconvenience may have to be imposed on visitors to public buildings. The public is becoming more accustomed to routine security checks and will readily accept these minor inconveniences.


Perhaps entrances and exits can be modified with a minimal expenditure to channel all visitors through someone at a reception desk. Individuals entering the building would be required to sign a register indicating the name and room number of the person whom they wish to visit. Employees at these reception desks could contact the person to be visited and advise him/her that a visitor, by name, is in the lobby. The person to be visited may decide to come to the lobby to ascertain that the purpose of the visit is valid. A system for signing out when the individual departs could be integrated into this procedure.


Such a procedure may result in complaints from the public. If the reception desk clerk explains to the visitor that these procedures were implemented in his/her best interest and safety, the complaints would be reduced. The placement of a sign at the reception desk informing visitors of the need for safety is another option.


Responding to Bomb Threats


Instruct all personnel, especially those at the telephone switchboard, in what to do if a bomb threat call is received.

It is always desirable that more than one person listen in on the call. To do this, a covert signaling system should be implemented, perhaps by using a coded buzzer signal to a second reception point.


A calm response to the bomb threat caller could result in obtaining additional information. This is especially true if the caller wishes to avoid injuries or deaths. If told that the building is occupied or cannot be evacuated in time, the bomber may be willing to give more specific information on the bomb's location, components, or method of initiation.


The bomb threat caller is the best source of information about the bomb. When a bomb threat is called in:


- Keep the caller on the line as long as possible. Ask him/her to repeat the message. Record every word spoken by the person.


- If the caller does not indicate the location of the bomb or the time of possible detonation, ask him/her for this information.


- Inform the caller that the building is occupied and the detonation of a bomb could result in death or serious injury to many innocent people.


- Pay particular attention to background noises, such as motors running, music playing, and any other noise which may give a clue as to the location of the caller.


- Listen closely to the voice (male, female), voice quality (calm, excited), accents, and speech impediments. Immediately after the caller hangs up, report the threat to the person designated by management to receive such information.


- Report the information immediately to the police department, fire department, ATF, FBI, and other appropriate agencies. The sequence of notification should be established in the bomb incident plan.


- Remain available, as law enforcement personnel will want to interview you.


When a written threat is received, save all materials, including any envelope or container. Once the message is recognized as a bomb threat, further unnecessary handling should be avoided. Every possible effort must be made to retain evidence such as fingerprints, handwriting or typewriting, paper, and postal marks. These will prove essential in tracing the threat and identifying the writer.


While written messages are usually associated with generalized threats and extortion attempts, a written warning of a specific device may occasionally be received. It should never be ignored.


Decision Time


The most serious of all decisions to be made by management in the event of a bomb threat is whether to evacuate the building. In many cases, this decision may have already been made during the development of the bomb incident plan. Management may pronounce a carte blanche policy that, in the event of a bomb threat, total evacuation will be effective immediately. This decision circumvents the calculated risk and demonstrates a deep concern for the safety of personnel in the building. However, such a decision can result in costly loss of time.


Essentially, there are three alternatives when faced with a bomb threat:


1. Ignore the threat.


2. Evacuate immediately.


3. Search and evacuate warranted.


Ignoring the threat completely can result in some problems. While a statistical argument can be made that very few bomb threats are real, it cannot be overlooked that bombs have been located in connection with threats. If employees learn that bomb threats have been received and ignored, it could result in morale problems and have a long-term adverse effect on your business. Also, there is the possibility that if the bomb threat caller feels that he/she is being ignored, he/she may go beyond the threat and actually plant a bomb.


Evacuating immediately on every bomb threat is an alternative that on face value appears to be the preferred approach. However, the negative factors inherent in this approach must be considered. The obvious result of immediate evacuation is the disruptive effect on your business. If the bomb threat caller knows that your policy is to evacuate each time a call is made, he/she can continually call and force your business to a standstill. An employee, knowing that the policy is to evacuate immediately, may make a threat in order to get out of work. A student may use a bomb threat to avoid a class or miss a test. Also, a bomber wishing to cause personal injuries could place a bomb near an exit normally used to evacuate and then call in the threat.


Initiating a search after a threat is received and evacuating a building after a suspicious package or device is found is the third, and perhaps most desired, approach. It is certainly not as disruptive as an immediate evacuation and will satisfy the requirement to do something when a threat is received. If a device is found, the evacuation can be accomplished expeditiously while at if the same time avoiding the potential danger areas of the bomb.




An evacuation unit consisting of management personnel should be organized and trained. The organization and training of this unit should be coordinated with the development of the bomb incident plan, as well as with all tenants of a building.


The evacuation unit should be trained in how to evacuate the building during a bomb threat. You should consider priority of evacuation, e.g., evacuation by floor level. Evacuate the floor levels above and below the danger area in order to remove those persons from danger as quickly as possible. Training in this type of evacuation is usually available from police, fire or other units within the community.


You may also train the evacuation unit in search techniques, or you may prefer a separate search unit. Volunteer personnel should be solicited for this function. Assignment of search wardens, team leaders etc., can be employed. To be proficient in searching the building, search personnel must be thoroughly familiar with all hallways, rest rooms, false ceiling areas, and every location in the building where an explosive or incendiary device may be concealed. When police officers or firefighters arrive at the building, the contents and the floor plan will be unfamiliar to them if they have not previously reconnoitered the facility. Thus, it is extremely important that the evacuation or search unit be thoroughly trained and familiar with the floor plan of the building and immediate outside areas. When a room or particular area is searched, it should be marked or sealed with a piece of tape and reported to the supervisor of that area.


The evacuation or search unit should be trained only in evacuation and search techniques and not in the techniques of neutralizing, removing or otherwise having contact with the device. If a device is located, it should not be disturbed. However, its location should be well marked and a route back to the device noted.


Search Teams


It is advisable to use more than one individual to search any area or room, no matter how small. Searches can be conducted by supervisory personnel, area occupants or trained explosive search teams. There are advantages and disadvantages to each method of staffing the search teams.


Using supervisory personnel to search is a rapid approach and causes little disturbance. There will be little loss of employee working time, but a morale problem may develop if it is discovered that a bomb threat has been received and workers were left unaware. Using a supervisor to search will usually not be as thorough because of his/her unfamiliarity with many areas and his/her desire to get on with business.


Using area occupants to search their own areas is the best method for a rapid search. The occupants' concern for their own safety will contribute toward a more thorough search. Furthermore, the personnel conducting the search are familiar with what does or does not belong in a particular area. Using occupants to search will result in a shorter loss of work time than if all were evacuated prior to search by trained teams. Using the occupants to search can have a positive effect on morale, given a good training program to develop confidence. Of course, this would require the training of an entire work force, and ideally the performance of several practical training exercises. One drawback of this search method is the increased danger to unevacuated workers.


The search conducted by a trained team is the best for safety, morale and thoroughness, though it does take the most time. Using a trained team will result in a significant loss of production time. It is a slow operation that requires comprehensive training and practice.

The decision as to who should conduct searches lies with management, and should be considered and incorporated into the bomb incident plan.


Search Technique


The following room search technique is based on the use of a two-person searching team. There are many minor variations possible in searching a room. The following contains only the basic techniques.


When the two-person search team enters the room to be searched, they should first move to various parts of the room and stand quietly with their eyes closed and listen for a clockwork device. Frequently, a clockwork mechanism can be quickly detected without use of special equipment. Even if no clockwork mechanism is detected, the team is now aware of the background noise level within the room itself.


Background noise or transferred sound is always disturbing during a building search. If a ticking sound is heard but cannot be located, one might become unnerved. The ticking sound may come from an unbalanced air-conditioner fan several floors away or from a dripping sink down the hall. Sound will transfer through air-conditioning ducts, along water pipes, and through walls. One of the most difficult buildings to search is one that has steam or hot water heat. This type of building will constantly thump, crack, chatter, and tick due to the movement of the steam or hot water through the pipes and the expansion and contraction of the pipes. Background noise may also include outside traffic sounds, rain, and wind.


The individual in charge of the room searching team should look around the room and determine how the room is to be divided for searching and to what height the first searching sweep should extend. The first searching sweep will cover all items resting on the floor up to the selected height.


You should divide the room into two virtually equal parts. This equal division should be based on the number and type of objects in the room to be searched and not on the size of the room. An imaginary line is then drawn between two objects in the room; e.g., the edge of the window on the north wall to the floor lamp on the south wall.


First Room-Searching Sweep


Look at the furniture or objects in the room and determine the average height of the majority of items resting on the floor. In an average room, this height usually includes table or desk tops and chair backs. The first searching height usually covers the items in the room up to hip height.


After the room has been divided and a searching height has been selected, both individuals go to one end of the room division line and start from a back-to-back position. This is the starting point and the same point will be used on each successive searching sweep- Each person now starts searching his/her way around the room, working toward the other person, checking all items resting on the floor around the wall area of the room. When the two individuals meet, they will have completed a "wall sweep." They should then work together and check all items in the middle of the room up to the selected hip height, including the floor under the rugs. This first searching sweep should also include those items which may be mounted on or in the walls, such as air-conditioning ducts, baseboard heaters, and built-in wall cupboards, if these fixtures are below hip height.


The first searching sweep usually consumes the most time and effort. During all the searching sweeps, use the electronic or medical stethoscope on walls, furniture items, and floors.


Second Room-Searching Sweep


The individual in charge again looks at the furniture or objects in the room and determines the height of the second searching sweep. This height is usually from the hip to the chin or top of the head. The two persons return to the starting point and repeat the searching technique at the second selected searching height. This sweep usually covers pictures hanging on the walls, built-in bookcases, and tall table lamps.


Third Room-Searching Sweep


When the second searching sweep is completed, the person in charge again determines the next searching height, usually from the chin or the top of the head up to the ceiling. The third sweep is then made. This sweep usually covers high mounted air-conditioning ducts and hanging light fixtures.


Fourth Room-Searching Sweep


If the room has a false or suspended ceiling. the fourth sweep involves investigation of this area. Check flush or ceiling-mounted light fixtures, air-conditioning or ventilation duds, sound or speaker systems, electrical wiring, and structural frame members.


Have a sign or marker indicating "Search Completed" conspicuously posted in the area. Place a piece of colored Scotch tape across the door and door jamb approximately 2 feet above floor level if the use of signs is not practical.


The room searching technique can be expanded. The same basic technique can be applied to search any enclosed area. Encourage the use of common sense or logic in searching. If a guest speaker at a convention has been threatened, common sense would indicate searching the speakers platform and microphones first, but always return to the searching technique. Do not rely on random or spot checking of only logical target areas. The bomber may not be a logical person.


In conclusion, the following steps should be taken in order to search a room:


1. Divide the area and select a search height.


2- Start from the bottom and work up.


3. Start back-to-back and work toward each other.


4. Go around the walls and proceed toward the center of the room.


Suspicious Object Located


It is imperative that personnel involved in a search be instructed that their only mission is to search for and report suspicious objects. Under no circumstances should anyone move, jar or touch a suspicious object or anything attached to it. The removal or disarming of a bomb must be left to the professionals in explosive ordnance disposal. When a suspicious object is discovered, the following procedures are recommended.


1. Report the location and an accurate description of the object to the appropriate warden. This information should be relayed immediately to the command center, which will notify the police and fire departments, and rescue squad. These officers should be met and escorted to the scene.


2. If absolutely necessary, place sandbags or mattresses, never metal shields, around the suspicious object. Do not attempt to cover the object.


3. Identify the danger area, and block it off with a clear zone of at least 300 feet, including floors below and above the object.


4. Check to see that all doors and windows are open to minimize primary damage from blast and secondary damage from fragmentation.


5. Evacuate the building.


6. Do not permit re-entry into the building until the device has been removed/disarmed, and the building declared safe for re-entry.


Handling of the News Media


It is of paramount importance that all inquiries from the news media be directed to one individual appointed as spokesperson. All other persons should be instructed not to discuss the situation with outsiders, especially the news media.


The purpose of this provision is to furnish the news media with accurate information and to see that additional bomb threat calls are rot precipitated by irresponsible statements from uninformed sources.




This pamphlet serves only as a guide and is not intended to be anything more. The ultimate determination of how to handle a bomb threat must be made by the individual responsible for the threatened facility.


Develop a bomb incident plan. Draw upon any expertise that is available to you from police departments, government agencies, and security specialists. Don't leave anything to chance. Be prepared


Bomb Incident Plan


1 Designate a chain of command.


2. Establish a command center.


3. Decide what primary and alternate communications will be used.


4. Establish clearly how and by whom a bomb threat will be evaluated.


5. Decide what procedures will be followed when a bomb threat is received or device discovered.


6. Determine to what extent the available bomb squad will assist and at what point the squad will respond.


7. Provide an evacuation plan with enough flexibility to avoid a suspected danger area.


8. Designate search teams.


9. Designate areas to be searched.


10. Establish techniques to be utilized during search.


11. Establish a procedure to report and track progress of the search and a method to lead qualified bomb technicians to a suspicious package.


12. Have a contingency plan available if a bomb should go off.


13. Establish a simple-to-follow procedure for the person receiving the bomb threat.


14. Review your physical security plan in conjunction with the development of your bomb incident plan.


Command Center


1. Designate a primary location and an alternate location.


2. Assign personnel and designate decision making authority.


3. Establish a method for tracking search teams.


4. Maintain a list of likely target areas.


5. Maintain a blueprint of floor diagrams in the center.


6. Establish primary and secondary methods of communication. (Caution-the use of two-way radios during a search can cause premature detonation of an electric blasting cap.)


7. Formulate a plan for establishing a command center, if a threat is received after normal work hours.


8. Maintain a roster of all necessary telephone numbers.

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