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By Steve Dillingham

With the millennium fever all but faded, we look to a new century filled with awe and excitement. We step forward in time, marveling over the achievements of the 20th century and wondering what the next 100 years could possibly bring. Will there ever be another time that produces such technological advances, economic progress or social changes? Keeping pace with the awesome accomplishments of the past century has not been an easy task and we must prepare ourselves for the possibilities of the future. Take, blasting safety for instance. We all know that safety is personal - a culture - promulgated not only by the company by which you are employed, but, by a sense of your own personal responsibility that must constantly be reinforced through awareness, training, and discipline. Great strides have been made in blasting safety since its crude beginnings, however, safety consciousness becomes even more important as technological advances and scientific progress are made in the coming years. It all begins with a positive safety attitude where every employee habitually examines each situation encountered, identifies potential hazards, and takes precautions to avoid those hazards.

Jan 1, 2002

By Zhao Jie, Christopher G. Smith

Commercial explosive use in China has been dominated by powdered AN-TNT mixes. Water gels and emulsions are now gaining market acceptance because they offer potential for better performance. Although raw material costs for emulsions initially may be more than AN-TNT mixes, the more expensive technology improves sensitization and leads to lower costs overall for mining operations. A recently completed study in northeast China compared microsphere-modified emulsions to AN-TNT and lower-cost emulsions. Testing of microsphere-modified emulsions at several pH levels indicated a high degree of stability and consistency of VOD. Using 42 mm blastholes in underground mines and 170 mm holes in sandstone open pit mining demonstrated the superior performance of glass microsphere sensitized emulsions. Comparisons of explosive cost, drilling cost, secondary blasting cost and muck pile profile were favorable to the microspheres-sensitized-emulsions. Noxious fumes with AN-TNT or with water-based systems that partially fail during detonation are also a concern. Efficient detonation of emulsion products sensitized with hollow spheres appears to reduce fume generation. Prolonged storage or exposure to water also is not a problem.

Jan 1, 1997

By Mark D. Kirkbride

This paper outlines the process for designing a hard rock blast in an underground coal mine. The coal mine is located in Western Kentucky and operates four continuous miner units at 7 unit-shifts per day. The mine operates in the Western Kentucky No. 11 Seam with local variations from 4.5 - 5.5 feet seam thickness. The seam has sporadic siderite deposits. Usually these deposits do not significantly interfere with the mining process. When previous siderite deposits were encountered they were small enough to drop an entry for a couple of crosscuts. The blasting plan was called for after a siderite deposit was encountered in the belt entry at about one third of the panel length. The other sides of the panel had been previously mined and sealed so the decision was made to mine through the siderite deposit with the continuous miner instead of abandoning the panel. The deposit was approximately 300 feet in length down the belt entry. Mining through the deposit with the continuous miner was expensive in both terms of production and of wear and tear on the continuous miner. A blasting plan for the siderite deposits was designed to minimize damage to the continuous miner should a similar situation occur.

Jan 1, 1999

By Michael S. Wieland, Thomas C. Ruhe

Delay blasting in underground coal results in shock waves traveling through the coal that can damage delay charges remaining in the blast pattern. Undetonated explosives which are dynamically desensitized or react sympathetically from shock wave impact ruin blast results. Such malfunctions, sometimes manifest as misfires, more frequently are covert weak detonations, and result in poor coal breakage and fumes with above normal toxicity. To reduce these mining hazards and resolve charge performance problems, the Bureau of Mines has developed and tested forty prototype rugged explosives in the laboratory. Rugged explosives work properly under difficult circumstances because they not only retain their shock initiation sensitivity but also are resistant to shock damage. This research investigation resulted in one candidate emulsion explosive, formulation #37, which passed all the permissibility tests required by MSHA approval regulations. However, approval was not granted because it reached shelf-life (would not shoot properly) seven months into testing. For research purposes, the remaining tests were conducted with a second batch of formulation #37. This paper discusses the prototype rugged explosive composition and permissibility test results. Where possible, for reference purposes, comparisons are made to a commercial product that has been approved. Further research work is required to overcome the noted deficiency of short shelf-life.

Jan 1, 1992

By Richard J. Mainiero, Marcia L. Harris, James H. Rowland

In the past several years, there have been a number of blasting-related carbon monoxide migration incidents. In each case, there have been some common factors that appear to be related to carbon monoxide migration. Geology, heavy confinement of the blast, close proximity to the affected structure, and open pathways into the affected structure are just a few. Prince William County, VA is an area undergoing a boom in suburban development. In the year 2001, more than 4,050 new homes were constructed within the county.1 In the new housing development located in Bristow, VA, trench blasting was utilized to excavate proposed sewage and utility lines. On November 8, 2002, a trench blast was conducted for the installation of utility lines. Later that evening a carbon monoxide detector alarmed in a nearby house. The gas company and fire department sampled for carbon monoxide and measured 100 ppm and more than 200 ppm on the first floor and in the basement respectively. Subsequent efforts to prevent migration of CO into the nearby homes met with mixed results. The only reliable technique for protecting neighbors from CO appears to be the placement of CO monitors in the homes. The events are presented and discussed.

Jan 1, 2004

By Dale Preece, Stephen Chung

The DMC-BLAST (Distinct Motion Code) has been developed for modeling bench blasting to one or two free faces such as choked blasting in surface gold operation and cast blasting in coal mining, respectively. This computer code has been used to assist the analysis of rock mass displacement after a blast was initiated in an orderly delay sequence. Applications of this feature can be found in the studies of dilution control in surface mining of gold as well as coal involving complex rock structures. Recently, DMC-BLAST has been modified to include a designated delay firing order coupled with variable rock strengths in the blasted media. This newly added feature allows the investigation of the effects of delay firing order on rock displacement in blasting a complex interbedded ore-waste structure. Examples of blasting a steeply dipping coal seams and bedded rock structure, especially in coal mining operations will be addressed and the comparison of efficiency in blasting in an up-dip as opposed to blasting in a down-dip direction will be discussed. Also covered in the paper is a new application of DMC-Blast to simulate a stope blasting underground. Simulations of blasting in a few selected types of timing/structure combinations will be presented in this paper.

Jan 1, 2000

By Juan Pablo Henríquez, Sebastian Lozano, Constanza Soto, Gonzalo Segura, Carlos Torres, Danko Morales

The Atacama Kozan underground mine, located in Tierra Amarilla, Atacama, Chile, was facing over-excavation and slow progress in drift construction, issues associated with the use of traditional explosive, ANFO. The presence of water in the blast holes required as well the use of cartridged emulsions, which extended loading times and increased operators’ effort. With loading times ranging around 76 minutes and lower advanced rate, Enaex Underground proposed the use of a pumpable emulsion-type explosive to optimize blasting, enhance safety, and streamline the operational process. This explosive is loading into the blasting holes using an UBT equipment (Unidad Bombeable para Túneles in spanish). This equipment allows mechanized loading, adaptation to small and medium diameter boreholes, ensuring compatibility with varying drilling profiles, integration with Atacama Kozan’s operational equipment and improvement in environmental and occupational conditions, with a measurable reduction in contaminant emissions and worker exposure risks. The implementation of this emulsion-based explosive allows an increase in productivity in drift development. A notable effective advance rate of 95% to 96% was achieved, alongside a reduction in overbreak in 7%, and a decrease in loading time to 40 minutes. Additionally, there was a 40% occurrence of drilling half cast, contributing to contour drift quality. The operation also benefited from a cleaner and safer working environment, enhancing operator ergonomics and reducing the need for jetanol and compressed air.

Jan 26, 2026

By Michael S. Wieland

Toxic fume concentrations from industrial mining explosives depend somewhat upon the type of rock (or other strata) confinement. Though traditional detonation theory disregards this influence, the work principal from thermodynamics reveals it, when the violent interactions that transpire within the rock blast are taken into proper account. Resolution of the work principle technique requires total thermodynamic equilibrium under constraint, so the nonequilibrium dynamics is rendered in that way, using an old trick from theoretical mechanics that revises the representation of forces. The rock pressure reduces to a four-component sum: the rock compressive strength and natural atmospheric pressure, as reckoned quasi-statically, and the gravitational influence and reversed inertial resistance, as reckoned dynamically. Tabulated specie concentrations and graphical trends reveal the dependency upon rock pressure, rock temperature and the fuel-oil percentage in ammonium nitrate mixtures (ANFO), used to illustrate the model. Rigid-wall test chambers have notable ullage (residual space), where rapid expansion influences the reaction quenching, yielding a fume spectrum unlike that for rock confinement; reported rock tests are therefore used for comparisons. For the thermodynamic regime where quenching occurs, seven concentrations are resolved, including carbon monoxide (CO) and total nitrogen oxides (NOX). Their trends yield inferences regarding the way unwanted charge desensitization from transitory hole-to-hole wave impact in conjunction with reduced rock pressure can yield nasty toxic fumes, the dark rusty cloud phenomenon!

Jan 1, 2005

By TTE-Europe GmbH

A few years ago, the term Track & Trace for explosives was only known in Europe and Brazil at most; the introduction of this technology is experiencing an undreamt-of boom worldwide. More and more countries are enacting legislation to introduce Track & Trace of explosives and follow Europe and Brazil on this path. At present, the world's leading manufacturers are already using such solutions, are in the process of implementing them, or are in the planning process. However, based on the experience gained in Europe, there are outstanding challenges for all manufacturers. These are questions of compliance, logistics, distribution, and, of course, especially, the necessary adaptation of the production environment. However, this development involves considerable effort on the part of the manufacturers. New devices for marking the explosives and digitally recording the data are integrated into the production process. This should be done as cost-effectively as possible, without restricting production capacity and speed, and with as few process changes as possible. This paper uses real-life customer experiences examples to explain paths from project design to real implementation. Lessons learned from the experience of European explosives manufacturers are presented, missteps are described, and solutions are identified. Individual steps along this path are explained, and solutions are told to avoid pitfalls and bottlenecks. Finally, it refers to the risk analysis and concrete examples in implementing the planning into production. Methods of marking various explosives are shown, and the use of Track & Trace to solve logistics tasks in picking and shipping explosives, including the data exchange with ERP (Enterprise Resource Planning) systems.

Jan 26, 2026

By Jean A. McIntyre

The Office of Surface Mining (OSM) has twice proposed rules for a blaster training and certification program to implement Sections 515(b)(15)(D) and 719 of the Surface Mining Control and Reclamation Act of 1977.

Jan 1, 1980

By Rolly Thorpe

Bulk emulsion explosives have been used at surface mines and quarries for many years. Recently, this technology has been adapted for underground use in relatively confined work areas and in smaller diameter blastholes.

Jan 1, 1994

By N H. Maerz

The digital image analysis program WipFrag has been developed under contract to INCO for use in quality control of underground blasting operations. This paper outlines the relevance of fragmentation to underground mining, the hardware and photography requirements, and key features and operating principles of the software.

Jan 1, 1995

By R. Wharton, M. Bagley

Following a series of papers relating to the certification of explosives for sale in member states of the European Union presented at previous ISEE conferences, this poster paper has been prepared to stimulate discussion and debate on the recently published European Directive on Pyrotechnic Articles.

Jan 1, 2008

By Alan R. Cameron, Alastair C. Torrance

An explosives underwater test facility has been established and commissioned in the Hunter Valley, New South Wales, Australia which allows the measurement of the actual shock and gas energies of the explosive

Jan 1, 1990

By D K. Joyce

Large diameter boreholes have become increasingly popular in underground mining. Drilling equipment can drill full rings, including vertical upholes. Special techniques are required to load upholes of three inch to eight inch diameter. The current methods for loading AN/FO and bulk or packaged emulsions are described.

Jan 1, 1988

By Jim Daley

This case history discusses a pre-split test conducted at BHP Mineralss Navajo Mine in Fruitland, New Mexico. The test was an extension of earlier pre-split testing conducted by Virgil Stachura of the U.S. Bureau of Mines in conjunction with Navajo Mine and WESCO Inc. which tested low-density product in 10.625 diameter holes.

Jan 1, 1996

By David R. Ziegler

Blasting complaints are as unpredictable as human nature. Being prepared to speak to the complainant, and having a good idea of what you should say, or what NOT to say, may affect the evolution, and eventual resolution of the complaint. The person taking that first phone call will probably not be responsible for resolving the complaint. However, the person in charge should respond to the complainant ASAP, the same day, if possible.

Jan 1, 1998

By Robert F. Flagg

This paper reviews the state of the art of precision explosive demolition particularly as it pertains to steel bridges. The two key factors affecting the acceptance of this type of demolition/are discussed as well as the physics and performance of the key explosive tool, the linear shaped charge. Methods of planning and executing typical bridge demolitions are discussed and examples of noteworthy engineering tasks given.

Jan 1, 1976

By Jaak J. K Daemen, Carol Geertson

A portion of a tailings impoundment may need to be removed with the expansion of an open-pit mine in northeastern Nevada. The tailings are saturated and consist of fine silty soil. During the removal of the tailings, they would have no support structure and vibrations induced by blasting in the pit could lead to slope failures.

Jan 1, 1998

By Eduardo Berger

This paper describes a mechanized loading system, the HYDRODOSE, which allows the use of pumpable emulsions in underground mining. It also describes a pumpable emulsion explosive for small diameter holes, HYDROMITE PDB. Included are test results carried out in two Chilean underground mines.

Jan 1, 1991