Low-order explosives

Although stable at ambient temperature, it begins to decompose below 100°C, and at 115-120°C the decomposition becomes a low-order explosion. 

Addition of ether to a nitration mixture (2-bromotoluene and cone, nitric acid) diluted with an equal volume of water in a separating funnel led to a low order explosion. This was attributed to oxidation of the ether (possibly containing alcohol) by the... 

Nitrosyl perchlorate, N0C104, is generally considered stable at room temperature and,by itself, should be completely safe. Decomposition begins just below 100 t, above IOOt (II5°-120ct) low order explosions occur (Ref 103) p-Nitrotoluene - HzSO4 mixtures explode when heated to 160°C... 

Properties White, pulped fibers, having a nitrogen content of 13.2-13.5 per cent, only partly soluble in ether-alcohol, completely soluble in acetone. Deteriorates under heat, but is stable in moist condition. In fiber form it is a high explosive gelatinized, it is a low-order explosive. The dry fiber can be detonated with mercury fulminate. Dry guncotton can be used as initiator for the detonation of wet guncotton. Rate of detonation (13 per cent nitrogen) 6300 m/sec. (d = 1.7). 

Low-order explosive mixtures made from commonly available chemicals have been termed improvised mixtures. The majority of the improvised mixtures used in criminal bombings in this country fall into two categories homemade black powder and homemade flash powders. These mixtures usually are confined in some container, such as a section of capped pipe, and initiated with an external burning pyrotechnic or homemade fuse. Homemade black powder is a mixture of potassium nitrate, sulfur, and charcoal. It is usually poorly made, and unconsumed particles are abundant in the bomb debris. The components of this mixture can be identified chemically using techniques described previously. 

Order has to do with the extent and rate of a detonation. A high-order detonation is one in which all of the explosive material is consumed in the explosion, and the explosion occurs at the proper rate. The proper rate in this case would be supersonic. Thus, a low-order explosion would occur as an incomplete detonation or at less than the desired rate. Yield involves the specific explosive material that is used, and order indicates the way in which the explosive detonated. The hazards to emergency responders are obvious. If an explosion is low order, not all of the explosive material has been consumed, and therefore the remaining material presents a hazard. Whether high or low yield, high or low order, all explosives should be treated as high-yield, high-order Class 1.1 explosives. 

When the structure of picric acid is compared with the structure of TNT, the only difference is the fuel that the nitro functional groups were placed on the number of nitro groups is exactly the same. The explosive power of picric acid is similar to that of TNT. There are other Class 1.1 to 1.3 materials that are nitro compounds and some that are made up of other chemicals. Black powder is a low-order explosive made up of a mixture of potassium or sodium nitrate, charcoal, and sulfur in 75, 15, and 10% proportions, respectively. It has an appearance of a fine powder to dense pellets, which may be black or have a grayish-black color. It is a dangerous fire and explosion risk, is sensitive to heat, and will deflagrate rapidly. 

Low-order explosion Materials that require excessive 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). 

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