Improvised explosives

Improvised explosive Improvised explosive Primary high explosive Primary high explosive Primary high explosive Primary high explosive Primary high explosive Secondary high explosive... 

Headquarters, Department of the Army, Explosives Improvised Munitions Handbook, 1969. 

See also Improvised ANFO, improvised explosive, improvised explosive mixture, poor man s C4... 

Explosives, Improvised. Improvised explosives are those usually made at the site from readily available oxidizers, fuels, banders and stabilizers. Some of compns were cited during oral presentation by Dr H.J, Matsuguma at Explosives Division, FRL, Picatinny Arsenal, Dover, NJ. No report was issued [See also Explosives, R D (Research Development)]... 

Hand grenades can be made from a piece of iron pipe. The fQler can be plastic or granular military explosive, improvised explosive, or propellant from shotgun or small arms ammunition. 

In general, improvised explosives are too complicated to prepare or too weak for steel cutting and most other sabotage tasks. However, if the problem is to get a quantity of lower velocity explosive for cratering or moving a large volume of earth or rock, a good simple one can be prepared from ammonium nitrate fertilizer. 

This improvised explosive can be used for attacking bridge abutments, or causing a landslide to block a mountain pass, close a tunnel, derail a train, or similar purposes. 

Because this improvised explosive is extremely insensitive, a booster is required to initiate it. A half pound charge of any high explosive in the bottom of the hole will be sufficient to insure detonation. 

Any number of mortar shells may be prepared either with the plastic explosive technique or by using the booster and attached by their primacord branch lines to a main primacord line for simultaneous firing. Or they may be interspersed along a road or trail with frag grenades or other improvised charges. 

The U.S. 3.5" high explosive antitank rocket (or similar rockets used by other modem military forces) can be cannibalized or altered and used in a variety of improvised techniques. It can be placed as a shaped charge or land mine or it can be launched either electrically or nonelectrically without use of the rocket launcher. Such improvised firing offers the advantages of rigging the rocket as a booby trap or, at least, permitting the operator to be well out of the area before the rocket fires. 

Good incendiaries can be improvised more easily than explosives and the materials are more easily obtained. On a pound for pound basis, incendiaries can do more damage than explosives against many type targets if properly used. There is a time lag, however, between the start of a fire and the destruction of the target. During this period the fire may be discovered and controlled or put out. An explosive once detonated has done its work. 

Mix equal parts of explosive and thermate incendiary. A powdered explosive is easiest to use, and TNT may be safely crushed with a wooden implement in a wooden container. Plastic explosive or dynamite also may be used, although in this case the explosive should be placed under the thermate so that the thermate will be directed upward. The thermate can be obtained from the AN M-14 incendiary grenade or homemade as described in the section on improvised incendiaries. ... 

Given the successes of the war on terrorism and the caveats listed above, research on sensors should address near term threats such as metals in weapons, explosives and improvised explosive devices (fEDs), and suicide packs, while continuing to address the longer-term threats of CBRN. 

None of the corporate security staff had been trained to identify combinations of common chemicals at their facilities that could be used as improvised explosives and incendiaries. 

Criminals and mentally disturbed or immature persons are both likely to be limited by the availability of materials and knowledge. In addition, criminals are quite likely to be more susceptible than the other groups to deterrence by visible and effective security measures. Thus, the first two groups — state-sponsored actors and non-state-sponsored terrorists — are the main threats on which explosives detection needs to focus. Unfortunately, this conclusion implies the need for detection of military, commercial, and improvised explosives and does not greatly help in narrowing down the issues. 

For over 20 years two improvised explosives containing the peroxide group have been of constant concern to legal authorities. Both triacetonetriperoxide (TATP) (2) and hexamethylenetriperoxide diamine (HMTD) (3) are easily prepared from readily available starting materials. Both compounds have been encountered for the first time by the Israel Police in the late 1970s and early 1980s [60], but... 

Inorganic oxidizers are widely used as blasting agents in mining and construction explosives and also in improvised explosive devices utilized by terrorists. Ammonium-nitrate-based explosives (e.g., ammonium nitrate and fuel oil — ANFO) have almost completely replaced the majority of dynamites. In addition, slurry and emulsion explosives, which contain mosdy ammonium nitrate and a small amount of other oxidizers, have become widely used. 

With a focus on trace forensic detection of explosives, especially for use in counterterrorism and to counter narcotics investigations, Fetterolf et al. [75] evaluated the use of ion mobility-mass spectrometry for explosives determinations. In this, explosives residues were collected on a membrane filter by a special attachment on a household vacuum cleaner. Although subsequent thermal desorption and analysis required only 5 s, fimits of detection for most common explosives were as low as 200 pg. The persistence of explosives on hands and transfer to other surfaces were also examined as were post-blast residues of NG on fragments of improvised explosive devices constructed with double-based smokeless powder. Finally, postblast residue from C-4, Semtex, and other explosives was found by IMS analyses on items of forensic and evidentiary value. These few out of many examples demonstrate that mobihty spectrometers are well suited tools for laboratory and on-site investigations, before and after the use of explosives. 

The nature of the explosive involved in a particular incident may be inferred from statements made by suspects or witnesses, from evidential material seized by investigators, or from chemical analysis. Expert scientific evidence about the fikely performance and effect of a suspect explosive will be needed to assist the relevant court in its deliberations. If the explosive is a well-known mifitary or commercial type then this is relatively straightforward. In the case of improvised or home-made explosives the issues can be more complex. This is particularly so where individuals have been experimenting with unusual chemicals. Unless the scientist has previous experience of the materials involved, the first step is fikely to be a search of the relevant literature [28-30]. 

Such calculations can give an approximate estimate of the Hkely maximum yield of explosives and explosives mixtures, and may readily be transferred to a spreadsheet for ease of use. In practice, small charges, particularly of improvised explosives, tend to produce less than their maximum output, and this needs to be estabhshed by experimental measurements. The results of simple calculations such as those above can be particularly helpful in the design of suitable experimental tests of explosives. 

S.A. Phillips, A. Lowe, M. Marshall, P. Hubbard, S.G. Burmeister and D.R. Williams, Physical and chemical evidence remaining after the explosion of large improvised bombs. Part 1 , J. Forensic Sci., 45 (2000) 324—332. 

Domestic bombings are characteristically accomplished by utilizing improvised low-yield explosives. An example of a low-yield explosive is black powder. 

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