The Largest Security-Cleared Career Network for Defense and Intelligence Jobs - JOIN NOW


Chapter 13

Booby Traps and Expedient Devices

During war and OOTW, booby traps can be found anywhere at anytime. They can kill or incapacitate their unsuspecting victims. This chapter provides information on booby-trap employment concepts, detection techniques, marking and recording procedures, and removal guidelines.

This chapter also provides an overview of expedient devices and their employment considerations.


US policy restricts the use of booby traps by US personnel. This does not preclude their use by other countries, so US forces may encounter them during operations.

The use of booby traps is limited only by the imagination of the force employing them. They--

  • Are usually explosive in nature.
  • Are actuated when an unsuspecting person disturbs an apparently harmless object or performs a presumably safe act.
  • Are designed to kill or incapacitate.
  • Cause unexpected, random casualties and damage.
  • Create an attitude of uncertainty and suspicion in the enemy's mind, thereby, lowering his morale and inducing a degree of caution that restricts or slows his movement.

In conventional operations, most booby traps found in the combat zone are constructed using military equipment and ammunition. Improvised traps are used during counterinsurgency missions in low-intensity conflicts.

The corps commander is the employment authority for booby traps. He can delegate this authority to the division commander. If authority is given to set booby traps, US personnel will adhere to the rules for international law applicable to armed conflict. There are several uses of booby traps that are prohibited. Remember, these restrictions are not observed by all countries; US personnel must still be cautious when approaching objects in areas where booby traps are supposedly prohibited.

International law prohibits the use of booby traps as follows:

  • Booby traps and other devices are prohibited if they are attached to or associated with--

  • Internationally recognized protective emblems, signs, or signals.
    Sick, wounded, or dead personnel.
    Burial or cremation sites or graves.
    Medical facilities, equipment, or supplies.
    Children's toys or other portable objects or products that are designed for their feeding, health, hygiene, clothing, or education.
    Food or drink.
    Kitchen utensils or appliances except in military establishments, military locations, or supply depots.
    Objects that are clearly religious in nature.
    Historic monuments, works of art, or places of worship.
    Animals or their carcasses.
  • Booby traps are prohibited in cities, villages, and other areas that contain civilians if combat between ground forces is not taking place or does not appear to be imminent, unless--

  • Booby traps are placed on or in the close vicinity of a military objective.
    Measures (guards, warning, or fences) are taken to protect civilians from booby-trap effects.


Booby traps are psychological weapons. They make the enemy cautious and slow it down. These actions, in turn, cause enemy casualties. Do not waste time attempting to set elaborate traps that are undetectable or impossible to disarm. Also, do not waste time developing difficult sites, because simple traps usually have the same chance of catching the enemy. Even if booby traps are detected and cleared, their aim is achieved.

The principles governing the use of booby traps and nuisance mines are identical, so consider using them in conjunction with one another. They have characteristics that make them suitable for use in different situations:

  • Nuisance mines are quicker to lay and safer to use than booby traps, and they are normally used in outside locations where they can be buried.
  • Booby traps are normally used in urban areas, structures, and places where mines are easily detected.

Booby traps and nuisance mines are particularly suited for defensive operations. They are used to--

  • Slow the enemy's advance.
  • Deny the enemy use of facilities and material.
  • Warn of enemy approach.
  • Deter the enemy from using ground not covered by direct fire.
  • Plan defensive operations.

In offensive operations, booby traps and nuisance mines are employed on an opportunity basis during raids and patrols. Formal instruction is not usually issued by the staff.

Exercise caution when using bobby traps in offensive operations because they may hinder the operation. In advance and pursuit operations, they are primarily used by patrols and raiding parties. They slow down enemy follow-up actions and hinder the enemy's repair and maintenance teams after raids.

The following considerations pertain to defensive operations but may be relevant to offensive operations and must be considered when briefing troops:

  • Booby trapping is rarely given a high priority and is usually peripheral to other engineer tasks.
  • Nuisance mines are more cost-effective than booby traps, unless booby traps are used in situations that allow their full potential to be exploited. If it is easier, use nuisance mines instead of booby traps.

To maximize the effect of booby traps and nuisance mines, the staff provides engineer commanders with the following information:

  • Purpose. Booby traps are time-consuming and dangerous to set. Do not waste time and effort setting traps that are unlikely to be actuated or that are not specifically designed to achieve the required aim. For example, if booby traps are being used against troops, small, simple traps designed to incapacitate will achieve this result just as well as complicated ones with large charges. If the aim is to destroy vehicles, use mines.
  • Location. The precise location for booby traps and nuisance mines can only be determined by the setting unit. Areas must be delineated and recorded so that there is no threat to friendly forces in the event of reoccupation.
  • Time setting starts and time available for setting. The time setting starts affects other engineer tasks, and the length of time available for setting governs the number of men required.
  • Number of safe routes required. Safe routes are important during general withdrawals where authority has been given to booby-trap positions as they are evacuated. They also provide safe areas for the covering force to launch counterattacks.
  • Likelihood of reoccupation. Even if the enemy has not detonated booby traps, they might have interfered with them. Therefore, do not set booby traps when areas are to be vacated to meet short-term tactical requirements or when reoccupation is expected soon.

Intelligence personnel provide information to assist the setting unit in maximizing the effect of booby traps. The nature and the type of traps required depend on the enemy unit. For example, while paying particular attention to dead space and defilade positions, use mines or widely dispersed traps (with large charges) against a mechanized enemy. Conversely, use small traps and AP mines (in places that afford cover) against an infantry enemy.


If the first obstacle or installation the enemy strikes is booby-trapped or nuisance-mined, he is delayed while he clears it. The enemy is further delayed by an increased degree of caution. His troops know that additional traps and mines can be encountered. Booby traps and nuisance mines are generally located--

  • In and around buildings, installations, and field defenses.
  • In and around road craters or any obstacle that must be cleared.
  • In natural, covered resting places along routes.
  • In likely assembly areas.
  • In the vicinity of stocks of fuel, supplies, or materials.
  • At focal points and bottlenecks in the road or rail systems (particularly the ones that cannot be bypassed).

The setting-party commander is responsible for the detailed siting and design of booby traps. Consider all the information about the enemy soldier and his operating procedures when selecting places and objects to trap. Also, consider the traps from the enemy's point of view and assess the courses open to the enemy when he encounters them. This can expose weaknesses in your initial plan and bring about changes to the proposed layout, or it can result in a different location being selected. In addition, determine the effort required by the enemy to bypass the traps. This shows whether the imposed delay justifies the effort required to set the booby traps in the selected location.


Booby traps are designed to--

  • Be actuated by persons carrying out their normal duties.
  • Take advantage of human nature.

The first type cannot be specifically guarded against because there is nothing about them or their situation to cause suspicion. The second type can often be detected because they are designed to make the person do something. The following traps fall in the second category:

  • Bait. Usually consists of objects that arouse someone's interest, such as attractive or interesting items that have apparently been left behind or discarded during a rapid evacuation.
  • Decoy. The most common decoy consists of two traps--one designed to be detected, the other designed to actuate when personnel deal with the first one. The first trap can be a dummy. A classic form of a decoy is to place booby traps or nuisance mines in locations from which the decoy mine can be removed.
  • Bluff. A bluff is a hoax and usually consists of a dummy trap.
  • Double bluff. A double bluff only appears to be a bluff. Personnel believe the trap is safe or can be disarmed. For example, a number of traps can be set that are disarmed when the detonating cord is removed from the charge. The double bluff is achieved by setting another trap that appears to be the same, but it actually explodes when the detonating cord is removed from the charge. Double bluffs rely on a reduced awareness and alertness caused by repetition.


There are two types of explosive booby traps--electric and nonelectric. Both types can be constructed using many different types of FDs. FDs can be secured to the charge (direct connection) or located away from it (remote connection). They are actuated by one or more methods. It is impossible to describe every type of trap that may be encountered; however, most are constructed and operated by using components and principles similar to those listed below:

  • FD.
  • Power source (battery, for example).
  • Connection (usually detonating cord or electric wires).
  • Blasting cap.
  • Main charge.

Figure 13-1 shows how typical electric and nonelectric traps can be made.

Figure 13-1. Typical electric and nonelectric booby traps


Occasionally, booby traps are actuated by electric devices that detect interrupted light beams, variation in acoustic levels, and magnetic influence. Most FDs found in the combat zone are simple mechanisms designed to be actuated by pull, pressure, pressure release, or tension release (Figure 13-2).

Figure 13-2. Methods of actuation


Procedures can be varied when it is safe to do so. For example, instead of connecting the FD to a charge already in position, preconnect trap components and then position the trap.

Small charges (up to 1 kilogram) are sufficient for AP traps, but larger quantities can be used to increase their effect. Shrapnel can be produced by packing stones, scrap metal, nails, or other material around the charge. AT traps require large charges (up to 6.75 kilograms for wheeled vehicles and 11.25 kilograms or more for tracked vehicles).


Follow the procedures listed below when assembling a remotely connected trap using an M142 FD (similar to the illustration in Figure 13-3):

Figure 13-3. Remotely connected traps

  • Design the trap and collect necessary materials.
  • Test the M142 FD.
  • Lay the detonating cord from the charge location to the FD location.
  • Position the charge.
  • Connect the detonating cord to the charge.
  • Prepare the coupler.
  • Tape a length (46 centimeters, minimum) of detonating cord to the coupler's blasting end.
  • Prepare and position the M142, set it to operate in the desired manner, and remove the round- or square-headed pin.
  • Ensure that the two detonating cords are not touching but can be conveniently connected when necessary.
  • Remove any materials and other signs of laying, and fully camouflage the area.
  • Arm the FD by removing the positive safety pin.
  • Arm the trap by connecting the two detonating cords.


Follow the procedures listed below when assembling a nonelectric, directly connected trap using an M142 FD (similar to the illustration in Figure 13-1):

  • Design the trap and collect necessary materials.
  • Test the M142 FD.
  • Prepare and position the charge for coupling to the FD, and prepare the explosive to receive a blasting cap.
  • Prepare the coupler and insert it into the charge.
  • Prepare the M142, set it to operate in the desired manner, and remove the round- or square-headed pin.
  • Remove any materials and other signs of laying, and fully camouflage the area.
  • Arm the trap by removing the positive safety pin.
Do not attempt to further camouglage the area after the trap is armed.



The setting-party commander must be given all the information and sufficient time to carry out a reconnaissance. This allows his plan and the soldier's briefing to be as complete as possible.


Once the commander has finished the reconnaissance, he makes a detailed plan, prepares the order, and briefs soldiers. The following points are covered:

  • Enemy intelligence.
  • Number and types of traps to be set.
  • Location and design of traps (precise or general).
  • Tasking and allocation of areas.
  • Recording, marking, and arming procedures.
  • Control measures.
  • Time requirements.
  • Material and equipment availability.
  • Rehearsal and equipment preparation.


Whenever possible, rehearse laying procedures. Thoroughly exercise control and safety measures so that any flaws in the system will be discovered. Lay practice traps and carry out arming and recording procedures. If you cannot rehearse at the trap location, hold the rehearsal in a similar area.


Setting booby traps is a dangerous task and it must be carefully controlled. Exact drills cannot be prescribed, but the following procedures should be followed as closely as possible:

  • Control point. The commander must establish a control point upon arrival at the trap area. The control point forms a headquarters and a material holding area. Also, safe routes start at the control point. If the rehearsal is conducted at another area, assemble all the troops at the control point before setting starts. At this time, relate the ground to the plan, confirm control measures, and check FDs and equipment for serviceability and adequacy.
  • Control of parties. Each setting party consists of one or two men. Clearly define the area where each setting party will work (use tape, if necessary). Position traps so that accidental detonation will not cause friendly casualties. Strictly control the entry to areas where traps are being set. In most situations, only the commander, setting parties, and a recorder enter areas. Troops who are not assigned tasks should remain at the control point unless otherwise authorized by the commander.
  • Marking. As with nuisance minefields, mark booby-trapped areas until they are evacuated. When possible, use standard booby-trap signs (Figure 13-4). When signs are not available, use temporary markings (any barrier or fence) to clearly indicate a booby-trapped area. Remove the temporary marking after the area is evacuated and before the enemy reconnoiters the area.

Figure 13-4. Standard booby-trap sign

  • Setting. Setting parties transport required explosives and material to the site. They do not arm FDs or traps until ordered to do so. If the setting party consists of one man, he remains with the trap until it is armed or until the commander directs him to leave. In a two-man party, one man returns to the control point and reports the completion of the task, and the other man remains with the trap. A setting party enters and leaves its area by the same route. If the route is not clearly apparent, personnel lay tapes to guide the commander and the recorder to the area.
  • Inspection and arming. The setting-party commander inspects traps for safety and camouflage before giving the order to arm them. He devises an arming plan that enables the setting parties to withdraw to the control point in a safe and logical manner. For example, in open areas, start arming at the furthest mine from the control point; in buildings, arm from the top down.


Booby traps do not distinguish between friend and foe. Correct reporting and recording procedures must be observed to avoid friendly casualties. The procedures for recording booby traps are the same as for nuisance mines (see Chapter 8). When traps are set in areas occupied by the enemy, they are not recorded. In this case, it is sufficient to note their location and type in after-action reports.

Tactical Reports

Information about booby-trapped areas must be provided in stages from the time they are established until they are cleared. This procedure allows up-to-date information to be annotated on operational maps at all concerned units and headquarters (see Table 13-1).

Booby-Trap Records

The setting-party commander compiles records for all booby-trapped areas on DA Form 1355 (Figures 13-5a and 13-5b). Strictly observe the instructions printed on the back of the form. Booby-trap records provide detailed information about the composition of an area, and they allow the area to be cleared quickly, with minimum casualty risk. They contain complete information on the number and types of traps set, as well as accurate and precise details on the location and design of individual traps. If a single record is not large enough to record all the traps set in a definable area, clearly note this fact and reference serial numbers of adjacent records. Submit the completed DA Form 1355, in triplicate, to the next higher headquarters.

Table 13-1. Tactical reports

Report By Whom and
When Initiated
To Whom
Details to be Included
Intention to set (required) Division commander, on deciding to set booby traps
  • Corps HQ
  • Controlling HQ
  • Purpose
  • General area to be booby-trapped (by grid coordinates)
  • Estimated number and types of traps
  • Estimated starting date and time
  • Estimated completion date and time
Siting (optional)
  • Setting unit, on completion of reconnaissance
  • Division ordering setting, only if materially different from intention-to-set report
  • Division ordering setting
  • Next higher HQ
  • Boundaries of booby-trapped area (by grid coordinates)
  • Number and approximate positions of safe routes, if any
  • Estimated number and types of traps
Start of setting (required)
  • Setting unit, when setting starts
  • Division ordering setting
  • Division HQ ordering setting
  • Next higher HQ
  • Time setting started
  • Estimated time of completion
  • Number and types of traps being set
  • Any change to the detail given in the siting report, and whether or not it was a result of orders
Completion (required)
  • Setting unit, when setting is completed
  • Division HQ ordering setting
  • Division HQ ordering setting
  • Next higher HQ
  • A trace on the largest scale map available, showing the boundaries of the trapped area
  • Full details of the area and buildings trapped (with sketch maps)
  • Full details of traps set, including design and location
  • Full details of all safe routes
  • Total number and types of traps
  • Time and date of completion
Changes (required) Division HQ ordering change
  • Next higher HQ
  • Any other unit holding information on existing traps
Full details of change

Figure 13-5a. Sample DA Form 1355 (front side) for a booby-trapped area

Figure 13-5b. Sample DA Form 1355 (inside) for a booby-trapped area


Soldiers must be aware of the threat that is presented by booby traps. They must also receive sufficient training to recognize locations and items that lend themselves to booby-trapping. Avoid overemphasis and strike a balance between what is possible and what is probable. For example, in medium-level operations, overemphasis of the booby-trap threat can be counterproductive by slowing momentum. This causes casualties that might otherwise have been avoided. In low-intensity conflicts where the use of booby traps and improvised explosive devices are probably widespread, training must be given high priority and emphasized at all levels.


Although many booby-trapped sites are similar, the items selected, the reason for their use, and the scale of the threat are quite different. In medium-level conflicts, booby traps are mainly used in recently contested areas. The items selected and the reasons for using traps are the same as those taught to our troops. Therefore, by anticipating the presence of traps, it is possible to isolate and bypass trapped areas. If this is not practicable, you can plan countermeasures, such as avoiding convenient and covered resting places along routes where mines can be located. At bridge or ferry sites that cannot be avoided, you must ensure that they are free of traps.

In low-intensity conflicts where booby traps are used to cause casualties, delays, or disruptions, no items or areas can be considered safe. Quality collective training in booby-trap awareness is necessary for all units. Rapidly disseminate booby-trap incident reports to all levels. This allows personnel to develop an understanding of the enemy's method of operation and a feel for what might or might not be targets.


The following rules and safety procedures can save your life and the lives of others--learn and remember them:

  • Suspect any object that appears to be out of place or artificial in its surroundings. Remember, what you see may well be what the enemy wants you to see. If you did not put it there, do not pick it up.
  • Examine mines and booby traps from all angles, and check for alternative means of firing before approaching them.
  • Ensure that only one man works on a booby trap.
  • Do not use force. Stop if force becomes necessary.
  • Do not touch a trip wire until both ends have been investigated and all devices are disarmed or neutralized.
  • Trace trip wires and check for additional traps located along and beneath them.
  • Treat all parts of a trap with suspicion, because each part may be set to actuate the trap.
  • Wait at least 30 seconds after pulling a booby trap or a mine. There might be a delay fuse.
  • Mark all traps until they are cleared.
  • Expect constant change in enemy techniques.
  • Never attempt to clear booby traps by hand if pulling them or destroying them in place is possible and acceptable.


The method used to neutralize or disarm a trap depends on whether it is electric or nonelectric, its design, and the accessibility of its components. Remember, a trap cannot be considered safe until the blasting cap or the detonating cord has been removed from the charge. This is your first objective and is particularly important for electric traps, which may contain a collapsing circuit.

Use the safest method to neutralize a trap. For example, if the FD and the detonating cord are accessible, it is usually safer to cut the detonating cord. This method does not actuate the trap, but inserting pins in the FD might.


Successful detection depends on two things--being aware of what might be trapped and why, and being able to recognize the evidence of setting. The first requirement demands a well-developed sense of intuition; the second, a keen eye. Intuition, like mine sense, is gained through experience and an understanding of the enemy's techniques and habits. A keen eye is the result of training and practice in the recognition of things that might indicate the presence of a trap. The presence of booby traps or nuisance mines is indicated by--

  • Disturbance of ground surface or scattered, loose soil.
  • Wrappers, seals, loose shell caps, safety pins, nails, and pieces of wire or cord.
  • Improvised methods of marking traps, such as piles of stones or marks on walls or trees.
  • Evidence of camouflage, such as withered vegetation or signs of cutting.
  • Breaks in the continuity of dust, paint, or vegetation.
  • Trampled earth or vegetation; foot marks.
  • Lumps or bulges under carpet or in furniture.


Detection methods depend on the nature of the environment. In open areas, methods used to detect mines can usually detect booby traps. Look for trip wires and other signs suggesting the presence of an actuating mechanism. In urban areas, mine detectors are probably of little use. You have to rely on manual search techniques and, if available, special equipment.

Continue Chapter 13

Join the mailing list

One Billion Americans: The Case for Thinking Bigger - by Matthew Yglesias