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By Robert Pumpelly

During my nearly 30 years with ATF, (Bureau of Alcohol, Tobacco, Firearms & Explosives), I conducted hundreds of inspections. In many cases hours of time were wasted because the licensee or permittee, who had basically done everything right, was not prepared for the audit. In these cases, required documents were scattered, personnel were unprepared and no plan was in place. This paper will provide some simple steps to avoid these embarrassing delays. A list of common violations is also provided.

Jan 1, 2010

By Lawrence C. Schneider

In the past decade regulations governing the manufacture, distribution, storage, and use of explosives have proliferated. These laws have been developed by a host of federal agencies with no coordination. The result has been contradictory and impractical standards, which once adopted, are resistant to change or repeal. The current OSHA standards are one example which is examined in detail. The Commonwealth of Kentucky has made progress in modifying these standards, and still providing protection to the blaster and the public.

Jan 1, 1981

By Thomas E. Brown

With the ever increasing public sensitivity to our environment, the blasting industry can no longer be concerned with just drilling and blasting. Government regulations, augmented by public pressure, require that the industry must be more diligent in preventing spills, disposing of distressed products and packaging materials, controlling fumes and dust, preventing product contamination, developing environmental impact studies, and preventing unnecessary regulations. These liabilities in conjunction with those of vibration, air overpressure and flyrock will continue to greatly impact the industry.

Jan 1, 1995

By Joseph A. Sohara, John J. Mullay, Curtis J. Keefer, Robert L. Schrepple

The desensitization of an explosive column by the action of a previous detonation (adjacent borehole, deck or detonating cord) is a vital concern to the explosives industry. Previous reports to this symposium and in other places have addressed this issue. However, this work has been mainly concerned with model or simulated conditions. No systematic study has appeared that utilizes an actual borehole environment. Thus the relation between this work and expected field performance is somewhat uncertain. The present paper attempts to partially resolve this difficulty.

Jan 1, 1990

By Gary L. Self, Ronnie Daniel

With the advent of large scale blasts utilizing overburden casting techniques, it was imperative that an ultra reliable surface delay system be developed. Shock tube and detonating cord surface delay systems have been hampered by the lack of a reliable easy-touse method of incorporating multiple paths of initiation to each hole. Two new redundant nonelectric delay systems have been developed utilizing multiple signal paths to allow a higher degree of safety and reliability. The first system designed uses a combination of detonating cord and nonelectric shock tube delays to allow multiple delay paths to each hole. The second system incorporates a new all shock tube delay system which allows multiple delay paths while minimizing over-pressure by eliminating detonating cord trunk lines. These two redundant systems have been used in over 500 production blasts without any misfires due to surface cut-offs or detonator malfunctions.

Jan 1, 1989

By Tyler Acorn, Tristan Worsey

A dozer operator at a surface gold mine accidentally drove a D10 off the side of a highwall. The blade of the dozer caught on the lip of a catch bench 60 ft. (18.3 m), down stopping its descent. The operator scrambled to safety in fear that the dozer would not hold.

Jan 1, 2014

By Leslie Taylor, Uli Leiste

In this paper, results from small scale testing conducted to determine pressure time profi les acting on a plate (taken to represent the bottom of a vehicle) at any given distance from the center of the plate will be presented. These results will be discussed in relation to visual observations of the upward moving sand.

Jan 1, 2008

By Roger Favreau, Patrice Favreau

The article reviews the aspects which contribute to the quality of the results from a blast with explosives, namely a good floor, no large blocks, easy mucking, and explains the mechanisms of the blasting process which decide on the quality of these aspects for a given blast method, and how these mechanisms can be simulated from basic principles. It proposes that good fragmentation size distribution can also be important if the rock is going to a crusher, e. g. for the ore in a mine and for the rock excavated in a quarry.

Jan 1, 2012

By Anthony Konya, Calvin J. Konya

The publication, RI8507, from the U.S. Bureau of Mines established an envelope equation that related scaled-distance to peak particle velocity in an attempt to predict ground vibration in the design phase of a blast. This has been further modified by Oriard, Dupont, Konya & Konya, and others to develop more refined prediction models for specific situations to obtain better predictions. While these equations can be an ideal starting point for a greenfield blasting project or a project with no given information, these equations can have errors.

Jan 1, 2018

By Calvin J. Konya

When blasts are designed, we normally assume the best case situation. We assume that all burdens and spacings will be properly drilled, holes will be properly loaded, initiators will fire at the nominal time and the explosives will release their full energy. This type of precision can be obtained at a machine shop where precision equipment is available to do machining, however, in the field, no matter how well a blast is designed on paper, it most likely will not be done in the exact manner in the field.

Jan 1, 1990

By Ed Jr Smith, Calvin J. Konya

The purpose of this paper is to describe the case history of a blasting project conducted jointly by Precision Blasting Services and Cherokee Explosives. It is the intent of the authors to show how blasting could be done in controlled fashion near very expensive computer controlled machinery. The job was done in minimal time with no complaints or allegations of damage in spite of the fact that blasting was conducted within five feet of the equipment and with the 32 acre plant fully operational, with machine operators working within 10 feet of the blasting site.

Jan 1, 1986

By Michael A. Barbaglia, Mark William Withey

The lift shot is an essential blast design in the execution of mine creation and expansion plans. Whether it be opening a new quarry, creating a new level in an existing operation, or for control of water, lift shots are utilized to create the desired results. Lift shots by their nature differ from conventional production blasts because they have no free faces for relief of the blast. Due to this fully confined state, the primary direction of the rock movement is vertical, and the potential for excessive vibration and fly rock generation is great.

Jan 1, 1994

By D Linn Coursen

Detonation propagates in the subject blasting agent at about 2.7 km/sec when it is heavily primed but explosion propagates in it at only about 0.43 km/sec when it is lightly primed. When propagating at 0.43 km/sec, it produces a borehole pressure that is slightly less than 1 kb, but no yellow fumes or other sign of incomplete reaction. It is a pumped AN/emulsion blend to which additional water is added by circumferential injection at the inlet of the hose through which it is pumped.

Jan 1, 1994

By Roger Holmberg, Dick Salomonsson

Nitro Nobel (the company was acquired by Dyno Nobel in 1986) originally developed non-electric initiation systems. These system were based on the 1967 invention of the shock tube fuse by Per-Anders Persson. Through licensees CIL and EB production and sales also started in Canada and the US. Early on, some accidental initiations of the tube occurred in production. It was found that static electricity was involved. After corrective action was taken - by changing the aluminium content in the tube core load - no further accidental initiations were reported until 1991.

Jan 1, 2002

By Robert B. Hopler

Hercules Incorporated has developed and introduced a totally new non-electric delay blasting cap system which utilizes a low energy gas detonation to activate the caps. Unlike any other initiation system, there is no hole-to-hole connection other than empty plastic tubing until the blast is to be set off. Only at that time, when all personnel and equipment are in the clear, is the special gas mixture introduced through the tubing. The actual time of firing is completely under the control of the operator, by pressing the fire button on the blasting machine.

Jan 1, 1977

By Joe Atalla, Jesse Desrochers, Rodrigo Hayashida, Joseph Mukendi Kabuya

The Mont-Wright mine stands as a prominent open-pit operation in Canada, renowned for its vast iron-ore reserves. However, the efficacy of its blasting operations, crucial for efficient production, has encountered challenges due to the diverse lithological compositions across multiple pits. This study presents a comprehensive approach to optimize blasting practices at Mont-Wright mine, tailored to the specific lithological characteristics of each rock domain. Through systematic analysis and experimentation, blasting guidelines were meticulously developed, aiming to enhance grindability and equipment productivity. The implementation of these guidelines promises significant improvements in operational efficiency and resource utilization, positioning Mont-Wright mine at the forefront of sustainable iron-ore extraction.

Jan 21, 2025

By David Scutt, David Noon

Blast crews are exposed to a number of major hazards including explosives and chemicals, ground conditions, machinery, unique work environments and specific blasting hazards such as fly rock and misfires. Unfortunately, injuries caused by sudden and/or unexpected movement of ground are continuing to occur. Blast crews are not equipped with the knowledge or tools to understand whether a high wall that they are planning to work under is safe.

Jan 1, 2011

By Ayman Tawadrous, Hendrik Botha, Simon St J Tose

The early miners and their mules always had the challenge of transporting unstable dynamite underground. The modern pumpable explosives, whilst far safer, still present a major logistics challenge for the mobile charging units (MCU). The challenge today is the efficient explosive delivery into declines, ramps, and vertical shafts, often requiring the MCUs to travel excess distances up and down to surface to re-load. Alternatively, the management of cassettes or ISO containers is utilized to deliver the pumpable base emulsion to the MCUs at the working face. Additionally, local laws and regulations regarding shaft clearance further compound the task and result in pausing other operations in the shaft or decline or ramp until the completion of the explosive transport. This paper examines the research & development challenges of dropping base emulsion down a vertical pipe to depths in excess of 1000 m (3280 ft.), either to an underground storage or directly into the MCU, depending on the depth. The boreholes (with pipes) are drilled in close proximity to the underground work areas. The paper also discusses the rheology of the emulsion within these vertical pipes as well as the economic benefits of such an innovative system. The learnings gained from this work, along with examples demonstrating the significant reduction in MCU travel and the safety benefits, are presented for the industry to consider moving forward.

Jan 21, 2025

By MacDonald B. Johnson, Douglass P. Bacon

With the advance of science, rise of public interest in environmental matters, and continuing erosion of air quality, Federal and state regulators are demanding an increasing complex array of data concerning emissions produced by burning and detonating energetic materials. The U.S. Department of Defense, one of the world's largest consumers of energetic materials, now must characterize combustion products resulting from open burning/open detonation disposal operations. The catch-all phrase "below detection limits" no longer satisfies the regulators who now want testing to delve into the ppt level for volatile organic compounds and ppt level for semivolatile organic compounds.

Jan 1, 1995

By Mark S. Stagg, Rolfe E. Otterness, Stephen A. Rholl

The Bureau of Mines has developed computer software to study the effects of initiator scatter on all aspects of the blasting process. The software is useful because it is difficult to obtain actual initiator data, particularly the standard deviation which is needed to express initiator scatter. The new software is structured to allow blasters to answer the question: how precise must initiators be to insure a successful blast? Successful is defined statistically in terms of a confidence level. The software can be used with any possible design since there are no restrictions due to size or complexity.

Jan 1, 1992