High-order explosives

Dynamite is by far the most commonly encountered high-order explosive used in destructive devices associated with criminal acts in this country. There are a number of types of dynamites, including straight dynamite, ammonia dynamite, blasting gelatin, ammonia gelatin, and nitrostarch dynamite. The color of these explosive compounds ranges widely - from off-white to nearly black. 

High-order explosion Materials that require moderate heat and reducing agents to initiate combustion. 

Detonation—A type of explosion of highest rate of progression, accompanied by a shock wave. The word detonation should not be used indiscriminately. A deafening bang does not signify detonation because of its loudness. Detonation is also called high order explosion in contradistinction to low order explosion by mere expansion (as of black powder). 

As judged by vacuum stability test data (see below), Explosive D is of a very high order of stability. The material has been found to withstand storage at ordinary temps for a period of twenty years with no evidence of deterioration, and at 50° for more than five years without marked deterioration... 

Repair and Reuse After Explosion. Although the risk of a high order detonation of a munition during disassembly is low, this hazard does exist. In the event of such an incident, it is a design requirement for the containment rooms to suffer only minimal damage and allow rapid refurbishment. To assure this capability, the containment room structural design criteria are more conservative than Department of Defense Explosive Safety Criteria would normally require. This is considered appropriate since vapor containment is so critical in this facility. 

To achieve high-order detonation in secondary explosives, it has always been necessary to allow much longer delays in order to let the low-order process initially started "jump to high order [Compare with Detonation (and Explosionjby Influence] Note 2 In a review of 23 papers on initiation, ignition, and growth of reaction presented at the 4thONRSympDeton bv G.P. 

All military explosives are considered to possess stability of a high order at temperatures -40 °C to +60 °C but each has a higher temperature at which decomposition rate becomes rapidly accelerated and stability is reduced. As a rule of thumb, most explosives become dangerously unstable at temperatures above +70 °C. 

The c is chosen best from a plot of the data for a shot with a long run to high-order detonation. The data used to evaluate c can come from an experiment in which the shock was accelerating, and high-order detonation need not be observed. The value of c is treated as a constant for that particular explosive formulation and density. This procedure typically gives a lower initial shock velocity value than does Technique 1. 

No attempt to integrate this equation has ever been made. However, the availability of modem high speed digital computing devices brings its numerical integration within the realm of possibility. However, up to the present time, few clear cut cases of high order thermal explosions have been reported in the literature. 

If, however, the expl is under confinement, the deflagration might undergo transition into explosion or detonation. Confinement permits rapid increase in pressure with consequent rapid increase in the rate of deflagration. If the rate reaches the value of 1000-1800 in/sec, it rs already not deflagration but "low-order detonation. If the rate increases to 5000 m/sec, the detonation is "high-order ... 

CA 46, 7332 (1952) (A demolition expl of high strength and of low sensitivity to impact and high order of detonation is composed of NG 4- 10 S and cellulose acetate having a viscosity of less than 80 secs combined AcOH content 54"56% plus other ingredients) ll)Anon, "Explosives and Demolitions", US Dept of the Army Field Manual FM 5-25... 

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