Sensitivity to Electrostatic Discharge

The electrostatic discharge sensitivity of LS is significantly higher than such sensitivity in other primary explosives. This creates problems for the technology used in its production and processing. 

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Sensitivity to Electrostatic Discharge. Thru 100 mesh material, confined 6.0 joules, unconfmed 0.025 joules (Ref 10)... 

Electric Spark Sensitivity to. MF is capable of being ignited by a spark from a person charged to less than 5000 volts, a condition that is possible in plant operations. Brown et al (Ref 27) give for Sensitivity to Electrostatic Discharge 0.025 joules (Ref 34)... 

Sensitivity to Electrostatic Discharge, in joules., 0.010 for unconfined and 0.012 for confined... 

Some work was also done by Consaga et al. on cyclodextrin nitrates with a view to replacing NC [5]. The composites of this invention are mixtures of (i) a cyclodextrin nitrate or a mixture of cyclodextrin nitrates and (ii) an energetic organic nitrate plasticizer. These composites are useful as replacements for nitrocellulose (NC) because they are more thermally stable and less sensitive to impact and yet have comparable or greater energy content than NC. However, cyclodextrin nitrates are dry powders that are sensitive to electrostatic discharge (ESD). 

This test is used to characterize expls, (submitted by various directorates of the Arsenal from the point of their relative1 sensitivity to electrostatic discharges. The test does not seem vety reliable, since widely varying results are obtd, depending on the humidity, the operator and the test setting... 

TNT, like RDX and Composition B, is not classified as dangerous with respect to hazard from electric sparks. Sensitivity to electrostatic discharge of TNT (thru 100 mesh) is 0,06 Joules (unconfined) and 4.4 Joules (confined) TNT can be detonated by electric discharge (Ref 108)... 

Previously reported [2] as a non-melting solid exploding on attempted purification, this proved a very shock sensitive (40 kg/cm) solid of m.p. 150°C. Less sensitive to electrostatic discharge and friction. Methods of explosibility testing for very small quantities of very sensitive materials are described [1]. 

If one simply mixes a solution of lead nitrate (or acetate) with a solution of sodium azide, a precipitate of nearly pure lead azide forms which can be washed, filtered and dried, and utilized in a detonator or other explosive device. However, this lead azide is at best a flulTy fine powder (not unlike that produced by the reaction of hydrazoic acid with lead nitrite (Figure 9), very sensitive to electrostatic discharge, difficult to pour into small detonator cups, and difficult to compact by pressing. It is, however, a stable and powerful initiator. 

The only nearly pure (99+%) form of lead azide used today in the United States is the so-called colloidal lead azide made by quickly mixing dilute solutions of lead and azide salts. Despite the information in reference [5], colloidal lead azide is neither colloidal in particle size (the specification [6] calls for an average of particle size of 5 pm) nor safer to handle, as this form of lead azide is particularly sensitive to electrostatic discharge. It is used in contact with bridge wires in electric detonators (sometimes applied by mixing with a lacquer binder). The process as developed commercially is a proprietary product, and only small amounts are made as needed. 

This chapter deals explicitly with the sensitivity of the explosive azides to impact and friction. Chapters 5 and 6 discuss, respectively, their sensitivity to electrostatic discharge and to heat and radiation. Shock sensitivity, although a form of impact sensitivity, is discussed in detail in Chapter 7. Although these are not the only types of stimulus that may be applied to an explosive, they are representative of the technology. 

Static electric discharge is a serious problem in the electronics industry. Electronic devices are extremely sensitive to static electric discharges. Examples of the sensitivity to electrostatic discharge (ESD) are given in Table 2 (26). 

Note that Mix 6 is 264 times more sensitive than Mix 1. Mix 2 and 4 are typical of those used in fireworks salutes, and they produce essentially the same sound output. However, there is a factor of at least 4 in their sensitivity to electrostatic discharge. 

Precaution Dust may present explosion hazard dust is very sensitive to electrostatic discharge and may be ignited ground equip. 

Since the 2002 discovery of nano-explosive devices using solid-state oxidants in porous silicon at room temperature, the technology has reached the stage where several applications are considered. Issues of interest are the cost-effectiveness of fabrication, future integration with CMOS technology, the long-term stability, and the sensitivity to electrostatic discharge. 

MF is highly sensitive to electrostatic discharge— ESD. The published values show a significant spread, and range from 0.51 to 0.62 mJ (Majzlik and Stmad tmpublished work) [70] to 25 mJ [30]. The comparison of sensitivity to BSD with other primary explosives is shown in Fig. 2.21. MF can be initiated by discharge of static electricity generated from the human body [29]. 

From the above data it can be seen that copper azides are not significantly more sensitive than LA to mechanical stresses with just one exception—cuprous azide. This, however, does not apply to sensitivity to electrostatic discharge where copper azides are shown to be in most cases below the lowest possible limit obtainable with standard apparatus. The estimations of initiation energies by Lamnevik are 1—10 pJ [107], Holloway obtained 0.1-0.2 pJ for both CuNa and Cu(N3)2 [108],... 

Lead picrate forms several basic salts with varying lead content. They form citric yellow crystals practically insoluble in water or alcohol. Its explosive properties are similar to those of lead styphnate but its flammability is lower [10]. Sensitivity to electrostatic discharge is high (at the level of LS) and is the reason for the many accidents which occurred during its manufacture [12]. Sensitivity to impact is 2.5 J (it explodes by 5 kg hammer from 5 cm) [13]. 

Basic lead styphnate is quite sensitive to electrostatic discharge which makes its handling and loading particularly hazardous. The sensitivity of each form is different and varying degrees have been found by various researchers. The sensitivities to impact are reported according to the following sequence ... 

The sensitivity to electrostatic discharge is reported in the following order [24] Yellow amorphous (y) < yellow (a) < red (p)... 

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