Storage Of Explosives Research Articles

Energetic Material/Polymer Interaction Studied by Atomic Force Microscopy

AbstractThe interactions of energetic materials and polymers have important implications in safety, long‐term storage, and performance of explosives and explosive mixtures. Atomic force microscopy was used to investigate adhesion forces at the molecular scale of nine energetic materials, organic explosives and energetic salts, on eleven common polymers (polyethylene, polyvinylalcohol, poly(vinyl chloride), polycarbonate, polystyrene, poly(methyl methacrylate), styrene‐butadiene rubber, poly(4‐vinyl phenol), poly(2,6‐dimethylphenylene oxide), poly(2,6‐diphenyl‐p‐phenylene oxide) (Tenax®), and polytetrafluoroethylene (Teflon®)). Teflon was the least adhesive polymer to all energetic materials, while no distinct trend could be elucidated among the other polymers or energetic materials.

"Fooling fido"--chemical and behavioral studies of pseudo-explosive canine training aids.

Genuine explosive materials are traditionally employed in the training and testing of explosive-detecting canines so that they will respond reliably to these substances. However, challenges arising from the acquisition, storage, handling, and transportation of explosives have given rise to the development of "pseudo-explosive" training aids. These products attempt to emulate the odor of real explosives while remaining inert. Therefore, a canine trained on a pseudo-explosive should respond to its real-life analog. Similarly, a canine trained on an actual explosive should respond to the pseudo-explosive as if it was real. This research tested those assumptions with a focus on three explosives: single-base smokeless powder, 2,4,6-trinitrotoluene (TNT), and a RDX-based plastic explosive (Composition C-4). Using gas chromatography-mass spectrometry with solid phase microextraction as a pre-concentration technique, we determined that the volatile compounds given off by pseudo-explosive products consisted of various solvents, known additives from explosive formulations, and common impurities present in authentic explosives. For example, simulated smokeless powders emitted terpenes, 2,4-dinitrotoluene, diphenylamine, and ethyl centralite. Simulated TNT products emitted 2,4- and 2,6-dinitrotoluene. Simulated C-4 products emitted cyclohexanone, 2-ethyl-1-hexanol, and dimethyldinitrobutane. We also conducted tests to determine whether canines trained on pseudo-explosives are capable of alerting to genuine explosives and vice versa. The results show that canines trained on pseudo-explosives performed poorly at detecting all but the pseudo-explosives they are trained on. Similarly, canines trained on actual explosives performed poorly at detecting all but the actual explosives on which they were trained.

Comparison of the Explosion Thermodynamics of TNT and Black Powder Using Le Chatelier Diagrams

AbstractLe Chatelier diagrams may be adopted for the definition of thermodynamic loci of explosion in terms of internal energy with respect to the temperature for either the primary explosion or for the deflagrative, post‐combustion of the products of the first reaction with air, the afterburning reaction. In this paper, Le Chatelier diagrams are produced for TNT and black powder by using the CEA code. Pressure plots with respect to density or air/fuel ratio are also shown. These results are useful for the simulation of explosion (hydrodynamic codes), and more generally for the definition of safety of storage, transportation, and production of explosives and pyrotechnics. Furthermore, the method can be easily extended to any deflagrative pyrotechnic substances, for which information on explosion and afterburning effects are needed.

Volume‐Dependent Self‐Ignition Temperatures for Explosive Materials

AbstractIn this paper the differential equation of thermal explosion in the steady‐state approximation is established and solved. This solution is based on Fourier’s heat equation along with the Arrhenius heat source. The theory allows to draw conclusions on the thermal behaviour of any substance. The critical ambient temperature appears as a function of the apparent activation energy, Arrhenius temperature rate, temperature diffusivity, and the volume. The thermal stability of a chemically reactive material may be determined by means of these dependencies. Different volumes of five explosive materials were exposed to hot storage tests. These experiments generate appropriate kinetic parameters for these materials that are compared with known values from literature. Once these parameters are known, self‐ignition temperatures can be calculated for any arbitrary volume and boundary conditions. This is of major importance in the safe transportation and storage of explosives, munitions, and weapons.

Aluminum Foam-Lined Suppressive Shields for Safe Transport of Explosives

The manufacture, transportation, and storage of explosives in Canada and around the world pose serious challenges to explosives regulators and inspectors tasked with ensuring the safety of nearby populations. Explosives are routinely transported through, and manufacturing and storage facilities are often located close to, populated areas and traffic routes. This proximity increases the risk of severe casualties and infrastructure damage if there is an accidental or deliberate explosion. Even though an explosion is unlikely, the consequences can be severe. Several accidents that have involved explosives are discussed in the literature. These accidents highlight the devastation likely to result from an explosion and underscore the importance of finding cost-effective solutions to mitigate the effects on the population and infrastructure. This paper presents a research program designed to investigate the effectiveness of suppressive shield containers in reducing the blast pressure outside the container and eliminating fragment hazards from an explosion. Several types of suppressive shield panels, including panels lined with aluminum foam, were tested in a blast chamber. The results show reduced peak blast pressure outside the container by as much as 60% and in the incident impulse by about 58%. When the suppressive shield was lined with aluminum foam, a further reduction in peak incident pressure (up to 80%) was achieved.

Review of threshold quantities for the control of explosives in health and safety legislation in The Netherlands

This paper describes a study undertaken for the Ministry of Social Affairs and Employment in The Netherlands, to examine systems and limits for the control of explosives. An important part of the study was the development of a questionnaire and its issue to 11, key countries to obtain information on controls for the storage of explosives, especially fireworks. The responses to the questionnaire are analysed and used in conjunction with published information as the basis for our recommendations. The paper concludes that the threshold quantity for explosives in Dutch regulations should continue to be that quantity equivalent to 1000 kg of TNT. The paper also concludes that two threshold quantities for professional fireworks should be added to the list of explosives in the regulations. These proposed, new entries will cover report shells and other types of professional fireworks.

Risk-based regulation of technical risks: lessons learnt from case studies in Switzerland

In administrative law, various regulation strategies are used to limit technical risks. Frequently, their approach is deterministic. Risk-based regulation seeks to make law more efficient as well as more transparent. Its aim is to replace prescriptive, deterministic regulations by goal-oriented, probabilistic regulations, based on the criteria of cost-effectiveness and limitation of individual risks. The overall goal is to achieve more safety at less cost. The project 'Risk-Based Regulation' (1996-99) was intended to evaluate the feasibility of the approach from both technical and legal perspectives in the Swiss context. Nine case studies were carried out: storage and management of explosives (both military and civil), occupational safety, non-occupational accident prevention (mainly road accidents), fire protection, transportation of dangerous goods, waste disposal (conventional toxic landfills and radioactive repositories), and nuclear (reactor) safety. This paper summarizes final results of the case studies and draws general conclusions on the possibilities and limitations of implementing a risk-based approach. Its findings should be useful in formulating standardized approaches as envisaged by the European Commission under the heading of a 'Compass for Risk Analysis' (EC-JRC, 2000), and the safety guidelines of the so-called 'Swiss Agency for Technical Safety' (SATS), a new institution to be set up in Switzerland to integrate all federal regulatory bodies dealing with technical risks.

Compatibility testing of energetic materials at TNO-PML and MIAT

Compatibility is an important property for energetic materials and their additives such as a casing material or a binder. If these substances are incompatible an extra risk is introduced in handling and storage of ammunition and explosives. As part of a co-operation program between the Dutch TNO-PML and the Polish MIAT several compatibility tests are performed and compared with each other. All tests are performed according to a NATO Standard in which several tests are described which can be used to determine the compatibility of an energetic material and an additive. These tests were performed on a huge set of energetic materials e.g. propellants (single and double base), explosives (RDX, PETN, HMX and TNT) and several additives like Teflon, polypropylene, self-burning case, inhibitors etc. The results of pressure vacuum stability tests, dynamic thermogravimetry measurements and differential scanning calorimetry tests with several combinations of energetic materials and additives used during the co-operation program are presented and discussed.

New method for true-triaxial rock testing

Sub-surface structures provide attractive alternatives for storage of explosives and other military hardware. These facilities are commonly constructed at shallow depths where rocks have undergone extensive weathering and the geologic system contains joints and discontinuities. For underground munitions storage structures, risk and performance assessment studies have to be conducted to qualify the site and establish the “clear zone” in case of accidental detonation. At high loading densities, accidental detonation of a munitions storage facility can lead to rupturing of the overburden cover and creation of a hazardous fragment environment. The degree and extent of the “clear zone” is controlled by the overall characteristics of the geologic and engineered systems. Rock joint spacing is considered to be important in prediction of the hazardous range of blast-induced fragments and associated impact energy. A full scale tunnel explosion test was conducted in 1988 in the desert of California. The tunnel was constructed in a weathered, jointed, igneous rock mass with several, well defined discontinuities. The information from the overall characteristics of this tunnel was used to construct five scaled model tunnels, with simulated joints and discontinuities, under physical modeling at 1-g. The loading densities used in two of the model tests were equivalent to that of the full scale event. For the other three tests, loading densities were changed in order to determine the effects of the explosive weight on the jointed rockmass response. The tests reported in this paper are unique in terms of size and simulation method. Five large test beds were constructed in trenches filled with model material simulating the full scale jointed rockmass with through-going discontinuities at 20:1 scale. Geometric and strength related properties were scaled, whereas the density scale factors were maintained at unity. The model materials were formulated in such a way that similitude conditions between the properties of the full scale rock mass were maintained. Test beds were constructed by step-by-step casting of the model materials into the excavated trenches. Impedance characteristics of the model materials were matched with those of the host-ground for realistic simulation of the ground shock propagation. This paper provides a brief discussion on the tests performed and elaborates on the applicability and the economics of the physical modeling for studies related to explosives-underground-structures interaction.

Impact of joints and discontinuities on the blast-response of responding tunnels studied under physical modeling at 1-g

Sub-surface structures provide attractive alternatives for storage of explosives and other military hardware. These facilities are commonly constructed at shallow depths where rocks have undergone extensive weathering and the geologic system contains joints and discontinuities. For underground munitions storage structures, risk and performance assessment studies have to be conducted to qualify the site and establish the “clear zone” in case of accidental detonation. At high loading densities, accidental detonation of a munitions storage facility can lead to rupturing of the overburden cover and creation of a hazardous fragment environment. The degree and extent of the “clear zone” is controlled by the overall characteristics of the geologic and engineered systems. Rock joint spacing is considered to be important in prediction of the hazardous range of blast-induced fragments and associated impact energy. A full scale tunnel explosion test was conducted in 1988 in the desert of California. The tunnel was constructed in a weathered, jointed, igneous rock mass with several, well defined discontinuities. The information from the overall characteristics of this tunnel was used to construct five scaled model tunnels, with simulated joints and discontinuities, under physical modeling at 1-g. The loading densities used in two of the model tests were equivalent to that of the full scale event. For the other three tests, loading densities were changed in order to determine the effects of the explosive weight on the jointed rockmass response. The tests reported in this paper are unique in terms of size and simulation method. Five large test beds were constructed in trenches filled with model material simulating the full scale jointed rockmass with through-going discontinuities at 20:1 scale. Geometric and strength related properties were scaled, whereas the density scale factors were maintained at unity. The model materials were formulated in such a way that similitude conditions between the properties of the full scale rock mass were maintained. Test beds were constructed by step-by-step casting of the model materials into the excavated trenches. Impedance characteristics of the model materials were matched with those of the host-ground for realistic simulation of the ground shock propagation. This paper provides a brief discussion on the tests performed and elaborates on the applicability and the economics of the physical modeling for studies related to explosives-underground-structures interaction.

Mutagenicity of HPLC-fractionated urinary metabolites from 2,4,6-trinitrotoluene-treated Fischer 344 rats

The production and storage of explosives has resulted in the environmental accumulation of the mutagen 2,4,6-trinitrotoluene (TNT). In order to characterize the production of mutagenic urinary metabolites, 6-week old male Fischer 344 rats were administered 75 mg of TNT/kg or DMSO vehicle by gavage. The animals were placed into metabolism cages, and urine was collected for 24 hr. Following filtration, metabolites in the urine were deconjugated with sulfatase and beta-glucuronidase and concentrated by solid phase extraction. The eluate was fractionated by reverse-phase high-performance liquid chromatography (HPLC) using acetonitrile/water, and the fractions, were solvent exchanged in DMSO by nitrogen evaporation. Each HPLC fraction was bioassayed in strains TA98, TA98NR, TA100, and TA100NR without metabolic activation using a microsuspension modification of the Salmonella histidine reversion assay. Fractions 3, 5-18, 21, 22, and 24-26 contained mutagens detected by strain TA98. In the nitroreductase-deficient strain TA98NR, some mutagenic activity was lost; however, fractions 3, 6, 9-11, 15, and 25 clearly contained direct-acting mutagens. Fewer fractions were positive in strain TA100 (9-16, 19, 20, and 25) with less activity observed in the nitroreductase deficient strain TA100NR (fractions 3, 12, 14, 15, and 25). Although some mutagenic activity coeluted with known TNT metabolite standards, there were still many unidentified mutagenic peaks.

Mutagenicity of HPLC‐fractionated urinary metabolites from 2,4,6‐trinitrotoluene‐treated Fischer 344 rats

The production and storage of explosives has resulted in the environmental accumulation of the mutagen 2,4,6-trinitrotoluene (TNT). In order to characterize the production of mutagenic urinary metabolites, 6-week old male Fischer 344 rats were administered 75 mg of TNT/kg or DMSO vehicle by gavage. The animals were placed into metabolism cages, and urine was collected for 24 hr. Following filtration, metabolites in the urine were deconjugated with sulfatase and β-glucuronidase and concentrated by solid phase extraction. The eluate was fractionated by reverse-phase high-performance liquid chromatography (HPLC) using acetonitrile/water, and the fractions were solvent exchanged in DMSO by nitrogen evaporation. Each HPLC fraction was bioassayed in strains TA98, TA98NR, TA100, and TA100NR without metabolic activation using a microsuspension modification of the Salmonella histidine reversion assay. Fractions 3, 5–18, 21, 22, and 24–26 contained mutagens detected by strain TA98. In the nitroreductase-deficient strain TA98NR, some mutagenic activity was lost; however, fractions 3, 6, 9–11, 15, and 25 clearly contained direct-acting mutagens. Fewer fractions were positive in strain TA100 (9–16, 19, 20, and 25) with less activity observed in the nitroreductase deficient strain TA100NR (fractions 3, 12, 14, 15, and 25). Although some mutagenic activity coeluted with known TNT metabolite standards, there were still many unidentified mutagenic peaks. Environ. Mol. Mutagen. 30:298–302, 1997. © 1997 Wiley-Liss, Inc.

Safety Design in Explosives Testing Laboratories. Some examples at CERCHAR

AbstractFor more than forty years, CERCHARCentre d'Etudes et Recherches de Charbonnages de France. 's activities on explosives and related items have employed a staff of 10 to 20 people including 3 to 5 engineers. This staff, called LSEVLaboratoire des Substances Explosives de Verncuil , acts as the official French laboratory for testing and performing a variety of studies. The main research topics concern the safety in manufacturing of explosives, their transport, storage, and use, particularly in gassy and dusty mines. The same holds for hazardous chemicals that are potentially explosive or otherwise unstable. Related to these activities is the safety of the personnel involved in testing, which requires special attention to be paid to adapted procedures and instructions and to special devices or equipment, desiged for the most part by CERCHAR itself. Three examples of such designe are presented. Their objectives and advantages are disscussed.The first one is an explosion chamber for firing confined explosive charges up to 2 kilograms. This facility has the possrommy of being highly instrumented. Fragments formed in the detonation of deflagration regimes are totally stopped by the walls of the chamber.The second one is a cell device for daily storage of explosives. This device led to a very important reduction in the quantity of explosives handled by people in the same room. This avoids a possible catastrophic mass explosion when large samples are needed such as for modern, insensitive mining explosives. the design of the cell structure, based on ful scale experiments, limits an unexpected explosions to the contents of a single cell without propagation to the other cells.The third and last example presented is a movable wood barrier, located in areas where explosives are fired in the open. This barrier ensures a significant reducation in the blast effect. It allows the worker to stay in the immediate vicinty of charge during the final preparation stages i.e the connection of the detonator wires to the firing circuit.

Development of risk assessment techniques for use in the field of explosives and ammunition

Abstract After reviewing the techniques currently used for ensuring that the risks inherent in the storage of explosives and ammunition are maintained at an acceptably low level, a Risk Assessment technique is developed. The technique is based on a systematic approach to hazard identification through the use of a HAZOP procedure and Fault Trees together with occasional use of Event Trees where a single initiating event, such as a lightning strike, can lead to a number of top events. Quantification of the Fault Trees taking full account of the important contributions of human factors enables the frequency of unintended initiations to be estimated. Analysis of the consequence of these initiations allows the risk levels to be estimated. It is found that the risk levels achieved by application of the current NATO Safety Principles based on Quantity Distances are considerably lower for materials of Hazard Divisions 1.2 and 1.3 than 1.1. The present approach provides a significant advance over previous work in ...

Gas cloud explosions and resulting blast effects

The design of nuclear power plant structures to resist blast effects due to chemical explosions requires the determination of load-time functions of possible blast waves. Whether an explosion of a hydrocarbon gas in the atmosphere will occur in the form of a deflagration or a detonation is largely dependent on the type of flame acceleration process which is closely related to the rate of energy release. Flame propagations at normal flame velocities in a free explosible gas cloud will certainly not lead to detonation. However, with sufficiently large clouds — particularly under adverse boundary conditions — the flame acceleration could become so high that an initial deflagration changes into a detonative process. Results of recent investigations, which will be discussed in detail, show that in a free cloud with deflagrative ignition (flame, heated wire, sparks) the occurrence of a gas detonation can practically be excluded. Apparently, free gas clouds can only be induced to detonate by a sufficiently strong detonative initiation. Independently of the initiating event in the practice of damage analysis, it has become customary to describe the consequences of an explosion by means of the so-called TNT equivalent. Therefore, it is attempted to specify this equivalent for hydrocarbons by means of energetic considerations including the propagation functions for the case of spherically symmetric detonations. Analogous to the safety distances required in the handling and storage of high explosives, a mass-distance relation of the form R = k(L) 1 3 could be considered where L is the mass of spontaneously released hydrocarbon and k varies only with the structural shape of the blast loaded buildings. With the inclusion of an empirical relation which relates the quasi-static design pressure for a building with the normally reflected blast pressure of a blast wave, it is further attempted to establish a relation between the structural capacity of a building — i.e. the pressure resistance of a building structure for detonative dynamic loading and for quasi-static loading — and the unit-mass distance R L 1 3 .

On the bullet sensitivity of commercial explosives and blasting agents

This paper presents the results of experiments conducted to compare the projectile, cap, and bullet sensitivity of a number of commercial explosives and blasting agents. It was found that No. 8 electric blasting caps having either aluminum or copper shells yield essentially equivalent results in cap sensitivity testing. It was also found that the results of projectile impact tests could be correlated with the results of cap sensitivity measurements in the sense that a projectile velocity could be defined that represented the approximate threshold between cap sensitivity and cap insensitivity. The most important finding was that under ordinary conditions of confinement expected in the transport and storage of explosives, materials that were not sensitive to a No. 8 blasting cap were not observed to be sensitive to rifle-fired bullets.

Factors Determining the Amount of Damages

Two seemingly contradictory objections are raised against the traditional rules of liability for damage; on the one hand the requirement of fault appears to preclude just compensation of many persons who have suffered loss or injury, particularly such as is caused by modern dangers—motor traffic, the use, storage or transportation of high explosives, or the release of atomic energy. On the other hand damage caused by even the slightest degree of negligence may exceed by far what can justly be demanded from the person responsible.In Dunne v. North Western Gas Board no less that 46 coal gas explosions occurred simultaneously in the streets of Liverpool. The people injured were unable to recover because it turned out that the defect in the gas mains had developed without the fault of any person. In Fowler v. Lanning the plaintiff suffered injuries from pellets discharged from the defendant's gun. He pleaded this fact as a sufficient cause of action, leaving it to the defendant to explain the accident. That seems indeed to have once been the law. Today, however, the plaintiff has at least to allege negligence (if not intention) or to set out facts which “shout negligence”; only then does the rule res ipsa loquitur relieve him of the burden of proof, and then only of that burden alone. Ought not a hunter to be responsible for his gun, a gas board for its pipes?

A Primer on Explosives

THIS little book should prove of great value to those for whose benefit it has been mainly written, viz. the local inspectors under the Explosives Act, and those dealers whose trading necessitates the handling and storage of explosives.