Low-explosive

Flammable or Explosive Limits — the upper and lower vapor eoneentrations at whieh a mixture will bum or explode. The lower explosive limit of p-xylene is 1.1 pereent by volume in air, whereas the upper explosive limit is 7.0 percent in air. A mixture of p-xylene vapor and air having a coneentration of <1.1 pereent in air is too lean in p-xylene vapor to bum. Conversely, a mixture containing more than 7.0 percent is too rieh in p-xylene to bum. By subtraetion (7.0 - 1.1), p-.xylene is said to have a flammable range of 5.9. Materials having low explosive limits and wide flammable ranges are extremely dangerous. 

If an expl is to be used for APS (armorpiercing shell) application, the same requirements as above are pertinent, except that the impact sensitivity should be veiy low (Explosive D, TNT desensitized with wax, etc, would be suitable)... 

A mixture in the vapour phase exploded when exposed to light [1], Benzene-chlorine mixtures, though combustible, represent a low explosion hazard [2],... 

Self sustaining internal combustion propagating by means of molecular heat transfer slower than the speed of sound (the explosion mechanism gunpowder and other low explosives)... 

A self sustaining decomposition reaction propagating faster than the speed of sound by means of a shock wave (the characteristic property of high as opposed to low explosives). 

The objective in calculating explosion overpressure levels is to determine if a facility has the potential to experience the hazardous effects of an explosion and, if so, to mitigate the results of these explosions. The calculations can also serve to demonstrate where mitigating measures are not needed due to the lack of a potential to produce damaging overpressures either because low explosion effects or distance from the explosion for the facility under evaluation. 

Wang, J., M. Pumera, and G. Collins. A chip-based capillary electrophoresis-contactless conductivity microsystem for fast measurements of low-explosive ionic components. Analyst 127, 719-723 (2002). 

Interstitial Gas on the Shock Sensitivity of Low Explosive Compacts , Ibid, 349-58(1965) 13) Marjorie W. Evans et al, Shock Initiation of Low-Density Pressing of Ammonium Perchlorate , Ibid, 359-71 14) Donna Price T.P. 

Detonation (and Explosion), Ignition of Explosives and Propellants to. All propellants, pyrotechnic compositions and most "low explosives can be ignited to burn (See Vol 2 of the Encycl, pp B343 to B359, under Burning and Burning Characteristics... 

Explosives of this kind are known as deflagrating or low explosives. BkPdr and smoke- less propellants are examples. The simplest device for ignition is Bickford or miner s safety fuse, described in Ref 44, p B112-L. 

D38-R and D107-L. Known also as Low Explosives (See in this Glossary)... 

High-Explosive (HE). An explosive which when used in normal manner detonates rather than deflagrates or burns that is, the rate of advance of the reaction zone into the unreacted material exceeds the velocity of sound in the unreacted material. Whether an explosive reacts as a HE or as a LE (low explosive) depends on the manner in which it is initiated and confined. For example, a double base... 

Low-Explosive (LE). An explosive which when used in its normal manner deflagrates or burns rather than detonates that is the rate of advance of the reaction zone into the unreacted material is less than the velocity of sound in the unreacted material. LE s include propellants, certain primer mixtures, BkPdr, blasting explosives (See Ref 44, p B202-L), pyrotechnic compositions and delay compositions. Whether an explosive reacts as a high explosive or a low explosive depends on the manner in which it is initiated and confined. For example, a double base propellant when initiated in the usual manner acts as a LE. However, this material can be made to detonate if it is initiated by an intense shock. Conversely, a HE like TNT, can, under certain conditions be ignited by flame and will burn without detonation (Ref 40a, p 97)... 

Propellent (or Low-Explosive) Train. Combination of primer, igniter and propellant used for propelling artillery ammun ition. See Section 3, Part D... 

Squib. 1) (General). Any of various small size pyrotechnic or explosive devices 2) (Specific). A small explosive device similar in appearance to a detonator, but loaded with low explosive, so that its output is primarily heat (flash). Usually electrically initiated, and provided to initiate action of burning type munitions, pyrotechnic devices and rocket propellants. An electrical squib consists essentially of a tube containing a flammable material, and a small charge of powder compressed around a fine resistance wire connected to electrical leads or terminals (Ref 40a, p 135)... 

DETONATORS, IGNITERS AND PRIMERS USED FOR INITIATING LOW EXPLOSIVES (INCLUDING PROPELLANTS) IN MILITARY AMMUNITION (EXCEPT IN FUZES)... 

It has also been traditional to distinguish HE from low or propellant explosives. Here again the distinction is not clear-cut. Although a low explosive such as Black Powder probably cannot detonate, most smokeless powders can. Conversely, most, secondary, ex-plosives can be made to deflagrate. The main... 

The above classifications are not strictly applicable to the sensitivity of an explosive. Although it is true that most primary explosives are more sensitive than most secondary explosives, certain low explosives, eg Black Powder, are more sensitive than many secondary or even primary explosives... 

Presence of explosives a. sufficient for low-explosive function b. particularly hazardous to TM 9-1900 Ammunition General, 1941 Ammunition General, 1942 Ammunition General, 1945 Ammunition General, 1956... 

Light Green Smoke or marker ammunition. Presence of high or low explosive indicated by yellow or brown bands Bertram Smith, E.P. Dutton Co NY 1918 Catalogue of Enemy Ordnance Materiel Vols 1 2, US Army... 

Light Blue Practice ammunition. Presence of high or low explosive components indicated by yellow or brown band TM 5-280 Foreign Mine Warfare Equipment, July 1971 French Grenades and Grenade Fuzes Ministry of War, 15 Dec 1930... 

Esplosivi bassi (Low Explosives). To these belong weak Esplosivi da mina (such as Esplosivi antigrisutosi), DINAMITI with low NG content and Esplosivi di lancio o Esplosivi propellenti... 

High Explosive, Long Nose MB — Monoblock HC — High Capacity LE — Low Explosive... 

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