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By David Ziegler, John Babcock, Gregory Poole

On December 9, 2003 at 3:59 PM EST an earthquake with a 4.5 magnitude occurred in central Virginia. According to a survey on the US Geological Survey website, this quake was felt as far away as Bridgeton Missouri, approximately 683 mile from the epicenter1. We recorded the vibrations from this earthquake on 14 seismographs that were set up for monitoring vibrations from blasting activities in the area. Having this data gave us an opportunity to compare earthquake and blasting vibrations. The amplitudes, frequencies and duration were much different than vibrations from mining and construction blasting. A common question we get from homeowners when discussing vibrations from blasting activities is “How does that compare to the Richter scale?” The goal of this report is to provide some simple answers for that question. The Richter and Mercalli scale are compared to the particle velocities in order to show their relationship.

Jan 1, 2005

By Robert Hopler

That some time in the year 1872 there was organized an association composed of practically all of the manufacturers of gunpowder and other high explosives in the United States, the members of which said association were as follows: E. I. du Pont de Nemours & Co., The Hazard Powder Company, Laflin & Rand Powder Company, Oriental Powder Mills, American Powder Company, The Miami Powder Company, and Austin Powder Company of Cleveland, all of which or their successors are defendants herein; that the object and purpose of said association was the elimination of all competition between the members thereof in the shipment and sale of gunpowder and other high explosives among the various States and Territories of the United States; that the only manufacturers of gunpowder and other high explosives which did not join such association at the time of its organization were the California Powder Works, The Sycamore Manufacturing Company, and The Lake Superior Powder Company, but your petitioner alleges that each of said three last named companies

Jan 1, 2008

By Brian W. Stump

Seismic networks provide the primary technology for monitoring compliance with a comprehensive test ban treaty. The design goal of the network is the identification of possible clandestine explosions detonated below the earth’s surface and possible in the oceans. Complementary technologies such as infrasonic, hydroaccoustic and radionucleide (particulates and noble gases) monitoring supplement the seismic monitoring covering explosions in the atmosphere and oceans. Seismic sources that will produce detectable signals will be both natural and man made in origin. Naturally occurring events include earthquakes, many of which are beneath the oceans or deeper than it is possible to drill, and volcanic eruptions. Accurate locations of such events to depths of beyond 10 km precludes consideration of these events further.

Jan 1, 1995

By William Wilkinson, Vladisla Kecojevic

Current three-dimensional (3D) computer design technology leveraged into drill and blast planning and operations is changing the way engineers and operations approach drill and blast design. Additionally, Global Positioning Systems (GPS) technology that is now readily available to the civilian population is being implemented into the mining sector with a variety of new products specifically designed for drill and blast operations. The objective of this article is to discuss the steps involved with 3D Computer-Aided Design (CAD) of drilling and blasting, and the benefits such a design can provide in conjunction with GPS and drill monitoring systems.

Jan 1, 2004

By M. Hagfors

On the underwater testing of explosives, the measuring system consists of water filled test pond, tourmaline based pressure sensor, measuring cable and measuring unit, which supplies the DC current to the pressure sensor. Depending on the length of the measuring cable, it is always possible that some signal damping may occur in case the measurements are carried out without the signal amplifier to keep the measuring system as simple as possible. Therefore the length of the measuring cable should always be as short as possible.

Jan 1, 2006

By Aloke Verma, R. Singh, S. Jana, C. Sawmliana, P. Pal Roy

On July 21, 2004, a trial blast using electronic detonators was conducted in India for the first time in an opencast mine at Pundi-E Quarry of TISCO, West Bokaro. Orica-IEL conducted the test using electronic detonators. To provide necessary technical feedback on wider applicability, CMRI scientists also participated in the trial blast.

Jan 1, 2006

By Robert B. Hopler

The history of the first twenty years of the high explosives industry in the United States begins as an illustration of the free enterprise system at its best and ends with the industry virtually taken over by a single company: a company which strongly opposed the new explosive material at the beginning of the period. In the world of the late Twentieth Century we could almost compare this history to the opposition of the mainframe computer manufacturers to the introduction of the personal computer, and their later entry into, and attempted dominance of, that market. With computers in the twentieth century the attempt to dominate the market has not been particularly successful: with dynamite in the nineteenth century it was.

Jan 1, 1994

By Calvin Konya, Anthony Konya

State and Federal construction specifications require the Blasting Contractor to prepare a Master Blasting Plan which is reviewed by the Owner’s Representative. The Master Blasting Plan requires the Contractor to submit the design of a typical blast. Most blasting specifications also require the Blasting Contractor to submit Daily Blasting Plans. The Master Blasting Plan and the Daily Blasting Plan require that the Blasting Contractor also submit the types and quantities of explosives and initiators used. The specifications also request that the Blasting Contractor submit the pounds of explosive used per delay for both production and presplit blasts. The Blasting Contractor may also be required to predict the anticipated ground vibration and air overpressure levels for the proposed blasts. There are equations that can be used to predict the ground vibration. There are also equations that can be used to predict the air overpressure levels. The data for these equations were primarily derived from quarry and surface coal mine and some construction blasts. Data from major construction projects were analyzed in this study to determine new air overpressure propagation equations for construction blasting. These new prediction equations compare calculated results analyzed from field data with other existing air overpressure prediction equations. Production blasting air overpressure values are also compared to air overpressure from presplitting

Jan 1, 2015

"AQUILA Mining Systems Ltd. is a Canadian company that designs and develops monitoring, control and navigation systems for the surface and underground mining industries. In 1992, AQUILA Mining Systems began the development of technology for monitoring, controlling and positioning mobile mining equipment. In 1993, AQUILA completed its first field test with GPS receivers onboard ablasthole drill, and thus demonstrated the viability and strategic relevance of this technology in surface mining. Since then, AQUILA has installed GPS-based technology on drills and shovels in several Canadian mines. This paper will review the development of these systems and discussthe benefits the mining industry could realise through their production implementation."

Jan 1, 1997

By Dale S. Preece, Lee M. Taylor

Accurate computer prediction of the muck pile produced by a conventional blast requires modeling of the physics that occurs during the rock motion phase of a blast. The ability to predict the motion and the subsequent muck pile can have a significant economic impact on the mining industry.

Jan 1, 1990

By Dale S. Preece, Stephen H. Chung

Electronic detonators and the attendant precise detonation timing that they facilitate are having a measurable effect on rock blasting in terms of improved fragmentation and vibration control. These improvements are increasingly well documented which is driving the expanding use of electronic detonators. In spite of the growing body of positive evidence concerning the benefits of precise delay timing, very little work has been done to document the impact of electronic detonators on the movement of rock. In this study 3-D computer programs, used to predict blasting induced rock heave, including the effects of detonation timing, are used to simulate the effect of precise timing on rock movement. Implementation includes quick, precise timing between blastholes going down a row and then much longer delays between rows of blastholes. For example an effective blast design might call for precise 3 ms delays between blastholes along a row and then 60 or 72 ms between rows. Several options are studied in this paper using computer simulations to draw some conclusions about the underlying physics affecting the process and how precise timing might have a positive impact on blasting induced rock motion.

Jan 1, 2005

By Larry Schneider

"0 ne of the incentives that led to the development of non-electric shock tube initiation systems was the desire within the industry to improve detonator safety. And to the extent that nonelectric initiators are immune to the hazards of stray current and radio frequency energy found on normal blast sites, an advancement in safety has been accomplished. However, as a cautionary note, it is important to realize that there are still many hazards associated with any initiation system. While some of these hazards may differ from those associated with electric detonators, others are identical to those associated with any type of initiation system. For instance, contrary to what some uninformedblasters may believe, lightning remains a hazard when using nonelectric initiation as well as electric initiation."

Jan 1, 1995

By Alastair Grogan

In October of 2002, the author was retained by Public Works and Government Services Canada, on behalf of the Department of National Defense, to design, construct and test the effectiveness of a bubble curtain system at an underwater demolition range, near Victoria, BC. The purpose of the bubble curtain was to reduce the potential for fish mortalities at the site. This paper presents some of the elements of the design, along with the results of overpressure monitoring during blasting and compares the results of fish mortality and animal behaviors with and without the bubble curtain in operation.

Jan 1, 2005

By Wilfrid Comeau

This paper deals with the concept of a Quality-Assurance Manual, to the ISO-9001 Level, for quarry blasting in the urban environment. A case history of the incident, which led to its development, is presented in addition to three other case histories. These case histories are related to the potential effectiveness of a well thought-out and applied Quality-Assurance Manual in the conclusions. The basic principle, behind the development of a Q-A manual, is to supply a maximum of quality assurance with a minimum of disturbance to the operation of the quarry. This requires that every intervener in the quarry blasting operations, from management to labourer, be made responsible for the quality of their work. This basic goal can be achieved with a minimum of paper work and added bureaucracy. The manual respects the ISO principle that: Q-A Manuals are not recipe books and should allow for continuing technological developments.

Jan 1, 2003

By John Watson

The earliest known records related to mining document in dramatic terms the fact that mining methods have undergone significant change over the centuries. Wooden wedges, hammers and chisels, “fne setting”, to name a few, were the frst tools used to extract ore .or quarry rock for civilization. These inefficient tools and unsafe practices have been replaced today with some of the highest technology known to man. At the heart of most mining operations is the blasting program which utilizes one of the most efficient tools ever invented.. . explosives. Ever since they were invented, miners have been searching for more efficient products and methods with which to harness this “tool” and make it safer, reliable, and more eficient to use.

Jan 1, 1997

By Lex L. Udy

Properties of an explosive which itiuence its performance on rock breakage are analyzed in relation to the rock: hardness and a discussion on the interaction of an explosive with the rock during the blasting process is given. Theoretical concepts regarding ideal and non-ideal detonation are reviewed to explain how the physical and chemical factors of an explosive influence the rate of energy release and its consequence on blasting performance. While a lower velocity of detonation indicates a slowed chemical reaction it does not necessarily mean a loss in energy from the explosive. High density ammonium nitrate (HDAN) can be used effectively in the formulation of modern industrial explosives to slow the energy release rate with its attendant decrease in detonation velocity. Examples of blasting performance using custom formulated explosives with HDAN are presented.

Jan 1, 1995

By Michael S. Wieland

"Toxic fumes cause fatal andnonfatal incidents in underground mining, where the working environment tends to trap the fumes, hindering the restoration of non-harmful conditions. Workers can underestimate the residual fume toxicity and return to the work site too quickly. The toxic fumes from charge explosions depend upon a number things: formulation ingredients, mixture uniformity, water resistance, hole contaminates, rock hardness, and dust interactions. Transitory hole-to-hole waves can cause partial desensitization, ruin the reaction kinetics, and worsen the fume toxicity.Traditionally the toxic fume hazard for a candidate explosive is resolved from a requisite tally of fume components. The resolution starts with the fume spectrum, a tabulation of specie concentrations, transformed to standard reference conditions and readjusted to remove the air dilution. The resultant influence, which is referred to as relative fume toxicity RFT, is deduced by a formula rule with some chosen constants and the requisite concentrations. The RFT result is normally compared to an RFT criterion that represents the worst-case (maximum) tolerable fume toxicity, as stipulated by regulations or otherwise."

Jan 1, 1997

By Alastair Torrance, Mitchell Nipperess, Andrew Olsson, Italo Onederra, Gary Cavanough

Components of bulk explosive products include ammonium nitrate, water, fuel, stabilizers, and calcium nitrate. The physical attributes include prill/emulsion ratio, density, and viscosity and in the case of prilled ammonium nitrate, hardness, size distribution and fuel oil absorption. These components and attributes in conjunction with ground conditions determine all aspects of explosive performance including the risk of fume. This paper presents a fume risk assessment matrix of explosives components and physical attributes as a function of a simple description of ground conditions. Instrumentation to provide a measure of the quality of the explosive product are also described and these include both “on bench” physical measurements and laboratory analysis. “On bench” methods include “in hole “density, velocity of detonation (VOD), detonation pressure and detonation temperature. Part of the quality control process involves a mobile laboratory unit which at this stage can provide measurements of water content, ammonium nitrate content, calcium nitrate content, fuel content, prill characteristics and prill/emulsion ratio. This unit can be taken to sites to enable the testing of bulk and sensitized products at site rather than after transportation.

Jan 1, 2015

By Charles Pretorius

Electronic Delay Detonators (EDDs) with remote wireless programming and initiation capabilities have been successfully used for almost two years now. This system has been used in blasts mainly in South Africa, but also in South America and other countries in Africa. Initially the industry was slow to accept the idea of remote programming and blasting. The advantages were not fully understood and there were some safety concerns. With close to 200 successful blasts as a reference, a much better understanding exists. The advantage of such a system becomes even more significant when the programming of the detonators is digitally integrated with the blast design software as used by the Blast Engineer. It is now possible to import a survey file into the blast design software, to do the blast design using actual hole positions and to then export the designed firing times directly to the detonators down the hole via remote wireless communication. Mines that have been exposed to this technology favour it to the extent that wireless centralised programming is becoming the norm against which other electronic delay detonator technologies are measured.

Jan 1, 2005

By D. Pickering, R. Wharton

The deadline for meeting legal requirements relating to the sale of explosives in the European Union was 1 January 2003. The paper examines the range of materials that have already been certified by the different Explosives Notified Bodies as well as recent national and European Commission decisions relating to this work. The implications of enlargement of the European Union are also discussed as is the future role of the Great Britain Explosives Notified Body in certification and assessment.

Jan 1, 2003