Explosives definitions

The spectra in Figure 11.4 were recorded from headspace vapor either at room temperature (TNT, PETN) or elevated temperature (about 50°C for RDX). For TNT this corresponds to a saturated headspace vapor pressure of less than 10 ppb. At these levels strong signal is observed with relatively weak signal from room air. Explosives compounds that have been detected by the MS detector with high sensitivity include TNT, ADNT, DNT, NT, TNB, DNB, DMNB, RDX, HMX, EGDN, NG, PETN, and TATP. (see Explosive Definitions, page 329). 

Refs (to Detonation, Explosion and Explosives Definitions) 1) Taylor (1952), pp 1-9 la) F.P. Bowden A. Yoffe, "The Initiation of Explosions , UnivPress, Cambridge (1952) 2) Anon,... 

While Gray Yang are not denying the usefulness of such ideas, they consider that too literal an application on the distinction can lead to difficulties. For this reason they tried to unify both theories and this problem is discussed in their paper. They also examined the effect of fuel consumption on thermal explosions, definition of critical conditions and the effects of vessel shapes. Finally, the relationship between thermal explosion criteria and flame theoty described by Belles (Ref 2), as well as detonability limits were pointed out. Comments on the paper of Gray Yang of Profs R.R. Baldwin R. Ben-Aim are given on p 1061 of Ref 3 Refs 1) N.N. Semenov, "Chemical Kinetics... 

Several aspects of explosives definition, classification, fundamental features, important characteristics including their applications in various fields have already been discussed in Chapter 1. During last 50 years, the number of explosives reported in the literature has increased exponentially and it is therefore proposed to discuss the status of current and future explosives in this chapter. Toward the end, some areas have also been identified for further research in the coming years by the high energy materials (HEMs) community. 

A detailed account of the compatibility and stability of explosives-definition, implications and effect of various parameters such as temperature of storage, chemical constitution of explosive vis-a-vis other ingredients, sunlight and electrostatic discharge etc has already been given in Chapter 1 (Section 1.4.1). In this section, the test methods used to determine compatibility and stability are discussed. 

J.F. Roth, Nobelhefte 1954,pp 29ff Abstracted in Explosivst 1956(Combustion, initiation, detonation and explosion definition of terms)... 

The lower volatihty of JP-8 is a significant factor in the U.S. Air Force conversion from JP-4, since fires and explosions under both combat and ordinary handling conditions have been attributed to the use of JP-4. In examining the safety aspects of fuel usage in aircraft, a definitive study (15) of the accident record of commercial and military jet transports concluded that kerosene-type fuel is safer than wide-cut fuel with respect to survival in crashes, in-flight fires, and ground fueling accidents. However, the difference in the overall accident record is small because most accidents are not fuel-related. 

Definition of Dust E losion A dust explosion is the rapid combustion of a dust cloud. In a confined or nearly confined space, the explosion is characterized by relatively rapid development of pressure with a flame propagation and the evolution of large quantities of heat and reaction products. The required oxygen for this combustion is mostly supphed oy the combustion air. The condition necessaiy for a dust explosion is a simultaneous presence of a dust cloud of proper concentration in air that will support combustion and a suitable ignition source. 

FIG. 26-39 Definition of the venting capability EF of an explosion door in comparison with a plastic foil rupture disk. 

Among other things, one prerequisite necessaiy to calculate the pressure relief openings needed on the apparatus is knowledge about the explosion threat definition and venting system hardware definition. Tne various influences are summarized in Table 26-22. 

Explosion hazard definition Venting system definition... 

Explosion hazard definition Suppression system hardware definition... 

The sodamide must be free from sodium hydroxide and may be conveniently weighed under the 250 cc. of purified mineral oil which is used to rinse out the mortar. Care must be exercised in the use of old sodamide as it sometimes contains an explosive compound that might cause trouble. The nature of this explosive compound is not definitely known however, it appears to be associated with the development of a lemon yellow color. Should any part of the sodamide develop this color it is recommended that the whole be destroyed at once. 

EXPLOSIVE (Where the substance or preparation falls within the definition given in Notes 2a) 50 200... 

More speeifie definitions of explosives appear in legislation, e.g. in tlie UK under the Explosives Aet 1875 as amended, whieh eovers ... 

This energy measure is equal to Brode s definition of the energy, multiplied by a factor 2. The reason for the multiplication is that the Brode definition applies to free-air burst, while Eq. (6.3.15) is for a surface burst. In a fiee-air burst, explosion energy is spread over twice the volume of air. 

Accidental explosions arc potentially the most dmigcrous Uiey arc a major concern for any industrial plant that deals with either pressurized or flammttble gases. An accidental explosion occurs not by design and tliercforc is not similar to an intentional e.xplosion, where the conditions are planned and can be controlled. Accidental e.xplosions usuttlly arc the result of equipment failure or operator error. Although accidental explosions are by definition unforeseen events, tlie procedures discussed in the ne.xt chapter may be implemented either to minimize tlieir effects or to prevent tlicm entirely. 

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