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By Lon Santis, David Leidel, John Tatom, Meredith Hardwick

This paper describes the development and methodology of the Institute of Makers of Explosives’ Safety Analysis for Risk (IMESAFR), a risk analysis software program for commercial explosives operations. IME is a nonprofit safety and security association devoted to the safe and secure manufacture, transportation, storage, and use or disposal of commercial explosives in the US and Canada since 1913. The software methodology’s basis is the U.S. Department of Defense Risk Based Explosives Safety Criteria Team’s Safety Assessment for Explosives Risk (SAFER) software. A diverse group of industry and government experts contributed to modifications to SAFER that reflect commercial operations. IMESAFR is intended to supplement the American Table of Distances (ATD) and offer standardized methods of managing risk from a wide variety of commercial explosives operations where the ATD does not apply. The modifications made to SAFER primarily involved the addition of commercial activities and potential explosives sites (PES). A review of commercial explosives accidents and operations over the last 20 years served as the basis for establishing probability of event values. An industry survey of commercial PES types in the U.S. and Canada was conducted to identify and address critical differences in commercial structures as compared to the military structures in SAFER. The paper concludes with discussion of the potential uses for quantitative risk analysis (QRA) and a description of other explosion effects software

Jan 1, 2007

By Hernan Navea, Carlos Alvarado, Exequiel Nuñez, Matías Suarez, Jhon Silva, Bryan Townsend, Bryan Caceres, Felipe Pontanilla

Nowadays, technology dominates all aspects of human activities, and drilling and Blasting (D&B) is no exception. In most cases, the use of technology in D&B is focused on controlling individual activities such as drill performance, drilling advance rates, truck loading performance, etc. Still, in very few instances, the advantages of using technology along each D&B activity and how this influences the D&B results are documented. This paper shows how technology is applied to create a “relative hardness” model for the mine Caserones in Chile. In the future, the model can relate the relative hardness parameter to several variables, including excavation rate, fragmentation results, and vibrations. It can also be used in the explosives loading process, similar to the model used by Dyno Nobel’s Differential Energy (DE) technology. In the relative hardness model for Caserones, a design is loaded in the drill system, and data is collected during the advance of the blasthole. The collected data includes rpm, torque, pressure, etc. Then, an algorithm using the measured variables while drilling and known relationships between the properties of the rock and the drill's performance is used to classify the average relative hardness of the blasthole in four intervals: hard, medium, soft, and very soft. Optimization techniques and models used in the oil and gas industries to analyze drilling performance were adapted to implement the algorithm. The model uses the concept of mechanical specific energy (MSE). Using the data from the drill, the algorithm identifies the depth where the MSE reaches a minimum to calculate the “relative hardness” for the blasthole under analysis. The results are presented in maps highlighting the areas where hard, medium, soft or very soft rock masses are expected. That information can be used to anticipate areas where explosives with higher energy need to be used or to predict areas of the blast with additional digging difficulties and then lower loading rates. The paper shows examples where “relative hardness” maps are compared to drilling speed excavation rates and other variables.

Jan 21, 2025

By William Reisz

The explosives and blasting industry has a commendable safety and security record, especially over the last several decades. This is due in large part to our newer technologies, better training and education, engineering practices, corporate initiatives, our professional organizations, and whether we like to admit it or not - our regulatory agencies.

Jan 1, 2012

By Anne Caroline Costacurta Polli, Jose Rojas Cáceres, Roberto Mahler de Morais, Thais Costa Silva

The technology and the knowledge about the behavior of explosives and detonation accessories allowed to create new products for different situations by the restrictions imposed by the market. In a Brazilian underground copper mine the restriction occurred in the use of high grammage Det Cord in the development heading blasts perimeter holes. Enaex Brazil has developed Densiex UG™ (Low-Density Bulk Emulsion), a water-resistant bulk gassing emulsion with a density ranging from 0.60 to 0.90 g/cm³ to replace the high grammage Det Cord in blasts. That product is pumped in the same Mobile Manufacturing Unit (MMU) as Enaex Brazil's standard underground (UG) bulk emulsion. This product has a Lower Velocity of Detonation (VOD), vibration, and detonation pressure, which contributes to a better finishing of the drift, lower impact in the support structures, and lower generation on unstable rocks in the perimeter of the drift. This case aims to summarize the results of the work on the application of the Low-Density Bulk Emulsion in perimeter holes in an underground development gallery at an underground copper mine in Brazil. During this work, 10 horizontal drift blasts were performed using the Low-Density Bulk Emulsion, which presented an average density of 0.64 g/cm³, increasing safety, a 25% reduction in overbreak, a 23% reduction in scaling time, elimination of rework, and a saving of $135,000 per year for this business partner that immediately implemented this new product in all blasts at this mine.

Jan 21, 2025

By Paul Worsey, Larry Kenchel, David Randall, Mark Schmidt

The University of Missouri-Rolla (UMR) has historically maintained a manual, paper inventory of explosives stored and used at the university. Although this system was accurate for inventory control and reporting criteria, it was labor intense and delays in record keeping were predominant. A directive from the university’s administration mandated the development of a precise real time system “on-line” to maintain and control the explosives inventory in line with the universities new chemical tracking policies.

Jan 1, 2001

By Martin Langenderfer, Sergii Chertopalov, Catherine Johnson, Vadym Mochalin, William Fahrenholtz

The high temperature and high pressure of an explosive detonation can be used for the production of nanomaterials. The controlled detonation of explosive compositions along with the collection and characterization of reaction products encompasses a process known as detonation synthesis. The primary advantage of the method of detonation synthesis is the possibility for producing monocrystalline nanoparticles with diameters of less than 10 nm. In order to successfully synthesize nanomaterials via the detonation process, it is necessary that the explosive detonation is conducted in a sealed environment. This environment when pulled to a vacuum or purged with inert gas such as argon will reduce the oxidation of detonation reaction products. Detonation synthesis testing is currently being conducted in a 1.8 cubic meters (m3) (64.3 cubic feet (ft3)) ellipsoidal pressure vessel consisting of two interlocking half shells. The testing involves the controlled detonation of cast mixtures of Cyclotrimethylene-trinitramine (RDX) and 2,4,6-Trinitrotoluene (TNT) in conjunction with siliceous compounds to produce nanocrystalline diamond and silicon carbide. Alternative detonation environments including the presence of a cooling medium such as water or dry ice to absorb residual, post detonation, thermal energy and enhance the stability of the materials being produced have improved yield. Modifications to the explosive charge composition have an effect on the type and quantity of materials that can be produced. Doping of explosive charges with various organic and inorganic compounds has shown promise in the synthesis of materials that are difficult or uneconomical to produce through other methods. This paper outlines the process development of detonation synthesis facilities. Preparation of the pressure vessel to create a suitable detonation environment for the production of nanomaterials is examined. Formulation of explosive charge compositions and considerations involving test charge initiation are discussed in detail. Experimental results and analysis from initial testing as well as plans for future research are also evaluated.

Jan 1, 2018

By M E. Hanson, K Chong, R H. Jacobson, S C. Way

To create conditions for economic rates of mineral recovery in a deep, hard rock mass, enhancement of naturally occurring permeability is necessary, and may be achieved through explosives detonated in boreholes. Previous theories of explosively created permeability are reviewed and found to relate permeability solely to the degree of fracturing, neglecting porosity. A theory is presented that includes both fracture density and porosity, and its results are applied, together with a knowledge of explosive behavior, to derive design parameters for in-situ mining.

Jan 1, 1983

By Dennis J. Viscusi, James H. III Rowland, Lon D. Santis, Mark H. Weslowski

This paper describes the procedure for analysis of toxic fumes from the detonation of high explosives using the Large Chamber at the U.S. Bureau of Mines (USBM), Pittsburgh Research Center (PRC). This test is specified in 30 Code of Federal Regulations (CFR) Part 15.20 (g) as a requirement for the Mine Safety and Health Administration's (MSHA) approval of an explosive as permissible for use in underground coal mines. The Large Chamber replaced the Bichel gauge and CrawshawJones (C-J) apparatus in the 1989 revision of these regulations. To determine the safety of an explosive in terms of toxic gas production, the Large Chamber Test attempts to simulate mine conditions and miners' exposure to toxic gases from explosives.

Jan 1, 1995

By Ken Tunnel

In the spring of 2005, the Lake Superior Chapter of the ISEE invited me to speak about raw materials used for blasting, anhydrous ammonia and the effect of this important feedstock on the cost of ammonium nitrate.The invitation was extended because our company is involved in trading ammonia and the production of ammonium nitrate. In a response to a request to update that presentation, it struck me how events such as hurricanes Katrina and Rita can change the landscape of our businesses.

Jan 1, 2007

By G E. Frantii

In the exploitation of low grade mineral deposits, blasting engineers are vitally concerned with maximizing the efficiency of explosive fracturing of rock while simultaneously limiting deleterious environmental affects to acceptable levels. Efficiency can be inferred from radiating seismic waves. Likewise, seismic waves carry direct information on damage potential. The usual approach to this problem is to measure the maximum signal level close to a blast, where it is difficult to instrument and where the signal complexity is intensified by mixtures of wave types and by local heterogeneities. Near-field sites are usually more easily monitored and more readily interpreted. Therefore, a study is being conducted to determine if variations in multi-hole, delayed blasts produce measurable changes in the spectra of seismic waves recorded in the near-field and if these spectra can be correlated with close-in strong motions and affects. To date, power spectra for the well-developed phase Lg and its early coda have been computed and are found to vary measurably when nominal changes occur in blast conditions. Up to a distance of about 50 km the spectra of Lg and its coda appear to be dominated by body wave characteristics (thus source-controlled), whereas beyond 50 km path affects seem to dominate. Additional data must be collected to fully explore the consistency of near-field Lg observations and to verify their usefulness as diagnostics of the engineering affects of blasting.

Jan 1, 1977

By O E. Jr Crenwelge

Recently promulgated regulations governing blast induced ground vibrations in the mining industry contain a frequency criterion as one option for verifying compliance. This criterion is based upon an oversimplified method which assigns the entire peak particle velocity amplitude to one frequency. Depending upon the nature of the vibration time history, it is possible that this frequency may not even be one of the predominant frequencies of the signal. In addition, the criterion does not specifically define the data analysis approach to be used by the industry for obtaining either the amplitudes or the frequencies of the vibration components. And because personnel in this industry generally have little understanding of vibration phenomena, a number of different approaches are currently being used for satisfying the criterion. This paper presents a method for obtaining both the Fourier amplitude-frequency spectrum and the integrated predominant amplitude-frequency components for the vibration record. The method is both physically and mathematically correct and is in common use in a number of other industries. Therefore, it should be of help to regulators, blasters, and consultants charged with developing, enforcing, or implementing ground vibration criteria.

Jan 1, 1988

By Frank Sames

Blast vibration and airblast overpressure signals are generally rated and compared only by their maximum amplitude and the principal frequency associated with the peak pulse. The scaled distance concept is often used to predict peak amplitudes and can be applied for blasts in the same area of a mine to evaluate the statistical properties of a set of readings.

Jan 1, 1997

By K Ramachandra Rao

Joints, fractures and other structural defects bring anisotropic character Into a rock mass. Conventional methods of blast design In a rock mass consisting phyllites, mica schist etc., which are characterised by the presence of closely spaced, nearly vertical planar Joints, result In formation of large slabs which cannot be handled by the excavation and loading equipment without resorting to secondary blasting. Frequent secondary blasting Is not only expensive but also, Is a source of environmental hazard. Interruption of production cycles frequently, leads to uneconomical mining. This problem could be minimised by designing blasts which produce forces whose components along and across the joints/fracture planes Is lust sufficient to break the rock mass In both directions. Rock mass strength can be assessed from field and Laboratory tests. Projecting structural features with respect to bench orientation on a stereoplot helps In assessing magnitude and direction of force vectors required to fragment the rock mass to the desired size range.

Jan 1, 1995

By Katherine L. Heineken, Timothy J. Tope, Kim David Murphy

One method for small arms disposal is the use of a deactivation furnace or explosive waste incinerator. There are numerous hurdles a facility typically encounters to get the furnace or incinerator fully operational and permitted. For example, one Department of Defense installation was in the permitting process 7 years, which included numerous facility upgrades and modifications. This paper will discuss the technical approach for proactively addressing permitting issues and requirements and will identify potential pitfalls to avoid as well as ways to reduce costs. For example, when determining the waste profile, the facility should forecast its treatment needs (taking into account the net explosive weight limits of the furnace/incinerator) and then classify the wastes into "chemical families" based on the type and composition of the wastes. One waste from each family should then be selected for potential inclusion in the trial burn. Modeling the waste disposal can help to narrow down the number of wastes requiring characterization during a trial burn, as well as the number of analyses.

Jan 1, 1997

By I. Petropouleas, J. Croll, R. Bassett

A programme of tests on controlled internal explosions to a class of circular reinforced concrete columns, has allowed the relationships between the blast energy and the extent of local damage to be understood. These tests have also demonstrated the important additional effects on the damage levels of preexisting axial loads.

Jan 1, 2006

By Calvin J. Konya

Precision Blasting has designed easy to use, yet, highly powerful databases for storage and retrieval of blasting data. Three different Databases are available for blasting data management. The Vibration Data Management is a complete vibration record keeping system. The Blasting Data Management will record the information from the blasting report as well as the vibration data. The Explosives Inventory Control makes the control of explosives and initiators quick and easy.

Jan 1, 1991

By Valerie A. Rhodes, Catherine T. Aimone

Often blast damage litigation involves structural damage which clearly is not blast related. The fact that structures are observed to be damaged when blasting has taken place in the near vicinity of these structures does not necessarily mean that the damage was caused by blasting. If careful blasting and seismograph records were kept by the blaster which decisively indicate damage is not blast related, then other causes of structural damage need to be assessed. These include problematic soil characteristics and long-term changes in climate or subsurface soil moisture. This paper presents the evaluation process required to investigate soil problems leading to damage often attributed to blasting.

Jan 1, 1991

Casting design for bench blasting in surface coal mines is a new focus and a fairly recent success. This study aims at the development of a mathematical model to predict the throw of overburden material based on geological conditions of a bench and charges in blast holes. The procedure, derived on the basis of blasting theories and dynamics of the multiple-particle system, explores the mechanisms of casting rocks into pits. Implementing the model with a computer program is a part of the study. The computer program will supply quantitative data for evaluation. It serves the purposes of verification for the model and, hopefully, field applications.

Jan 1, 1988

By Karl E. Burger

Recently an experiment was completed at the Golden Sunlight Mine, a property owned by Placer Dome Inc. of Vancouver, British Columbia, to measure the Body Waves entering their highwall created by blasting. The purpose of the study was to assess the damaging effects of blasting on the highwall, in order to further slope stability. Stress and Strain experienced in the earth that is created as a result of blasting can be determined by knowing several important pieces of information. These include the compressional and shear wave particle velocities initiated by blasting, the Body Wave travel velocities in both the shear and longitudinal direction, and the densities of the rock in question. A series of equations based on wave theory can then be used to determine the stress and strain affecting the highwalls. The Blasting Engineer can then use this information to design blasts that create peak particle velocities less than levels that maintain the integrity of the highwalls. This paper first discusses the experiment used to measure the Body Wave velocities. It then traces through the subsequent calculations necessary to generate the information needed by the Blasting Engineers, the Mining Engineers, the Geological Engineers, and the Geophysicists to design blasts and develop open pit plans to alleviate unstable highwall conditions.

Jan 1, 1989

By A Gene Riggs

The Cerrejon Coal Project in Colombia, South America is one of the largest coal mines in the world. The mine is located in northeastern Colombia on the La Guajira penninsula. The area is in a remote valley 132 miles east of the city of Barranquilla.

Jan 1, 1984