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By Jeff Friedman

This paper addresses certain problems to be encountered when a blasting contractor agrees to provide indemnification. Nearly 100% of all blasting work is performed pursuant to a contractual agreement. Whether the explosives engineering firm works directly for the property owner, or for a general contractor by way of subcontract, indemnification agreements are generally required to protect owners, operators, general contractors, and other interested parties in the event there is subsequent litigation. These contractual requirements are typically referred to as indemnification and “additional insured” agreements. We will address the ramifications of contractual indemnification as well as “additional insured” agreements in this presentation. Some of the aspects of this paper will include:

Jan 1, 2004

By Alfred Osborne

Progressive cavity type pumps are widely used by commercial explosive manufacturers for pumping water gel, emulsion and emulsion / ANFO blend explosives. Tests by explosives companies and investigations into incidents have shown that this type of pump can develop dangerously high temperatures when operated deadheaded or dry. [i.e. with no flow of product through the pump.] In some tests and incidents, explosion or detonation of the explosive (or residual explosive) in the pump has resulted.

Jan 1, 2002

By Kenneth Eltschlager

Post-blast assessment techniques using off-site data which includes location, seismograph and photographic data were discussed during the Blaster’s Weekend at this year’s ISEE Conference. Blast and property locations with commonly available GPS units allow for the spatial relationships surrounding the blasting to be documented. When distances are coupled with the charge weight per delay, the scaled distance can be calculated to any structure for either compliance with the rules, or to project limitations. When blasting seismograph data is obtained, the scaled distances are then able to be plotted against ground and air vibration levels for post-blast assessment purposes.

Jan 1, 2007

By Neil E. Gehrig

The word "slurry" was used by Dr. Melvin Cook and Mr. Henry Farnam to describe a new blasting agent developed in 1956. This development, along with the development of ANFO triggered the Modern Era of Blasting. We have seen the results, a massive expansion in the commercial explosives industry. Someone once said, "You can't know where you're going if you don't know where you've been." With that in mind, this paper deals to some extent with the origin and development of slurry explosives and then with their future high potential.

Jan 1, 1982

By Raymond M. Dixon, Dale L. Ramsey

Upon being introduced to the MAGNETIC COUPLING concept,Balsinger,Inc. wanted to conduct field trials to explore the potential of Magnetic Coupling in the U.S.. Although the Magnetic Coupling Concept has been widely used, the U.S. proposed blasting criterion not previously addressed by the system. Modification to the system assembly and blasting accessories had to be made to make the system adaptable to our specific requirements. The field trials and system modifications are the basis of this paper.

Jan 1, 1990

By E. A. McCullough, Jackson B. C., S. K. Metz

Public perception is a significant challenge facing the explosives industry. The public often perceives that its needs and interests are in direct competition with those of blasting companies’, leading to conflict between corporations and the community. This misunderstanding lends to unnecessary political and regulatory hardship, and ultimately, social discontent. Although individual corporations implement strategies to address conflict, many of these techniques are insufficient. Consequently, stakeholders resort to expensive litigation. If blasting companies could reduce or eliminate the volume of judicial disputes, valuable resources could be re-directed to more productive activities.

Jan 1, 2015

By Shulin Nie, Mats Olsson

The mechanism of rock fracture by explosive is a fundamental in rock blasting. It is generally believed that the shock waves from the detonation initiate the fractures. Then the detonation gases penetrate into the fractures and elongate them. However, our previous researches indicated that the detonation gases do not contribute significantly to the fracture propagation. In our latest experiment, blasts have been carried out in 8 large granite blocks. The main goal was to study the fracture mechanism, namely to determine whether the shock waves or the detonation gases fracture the rock.

Jan 1, 2001

By Jack Eloranta

This paper documents the relationship between material handling and processing costs compared to blasting cost. The old adage, "The cheapest crushing is done in the pit", appears accurate in this case study. Comparison of the accumulated cost of: powder, selected wear materials and electricity; indicate a strong, inverse correlation with powder factor (lbs powder/long ton of rock). In this case, the increased powder cost is more than offset by electrical savings alone.

Jan 1, 1995

Increasingly specialized blasting needs require that the explosive energy available in a borehole be reliably known for representative blasting conditions. The underwater test, when properly performed, can yield such information and thus provide a reliable rating of explosives in terms of energy release. This paper reiterates the stringent experimental conditions to be satisfied, and data analysis and interpretation techniques to be followed to achieve this. This is supported by detailed experimental studies involving select parameters in both detonator and booster sensitive explosive compositions. The paper also illustrates the inadvisability of equating blasting performance with the commonly calculated energy values.

Jan 1, 2000

By Dale S. Preece, J Paul Tidman, Stephen H. Chung

A discrete element computer program named DMC_BLAST (Distinct Motion Code) has been under development since 1987 for modeling rock blasting (Preece & Taylor, 1989). This program employs explicit time integration and uses spherical or cylindrical elements that are represented as circles in 2-D. DMC_BLAST calculations compare favorably with data from actual bench blasts (Preece et al, 1993).

Jan 1, 1997

By Thomas Bakley, Rob Lee, Jay Rodgers

The present state of technology in Controlled Blasting uses standard explosives’ products to create a crack between holes along a desired line of break. The resulting pre-split, post-shear or cut line is often of variable quality with unwanted damage at right angles to the desired cut line. A new concept in Detonating Cord manufacturing has provided a radically different performing explosive. This new Cord has reduced the Velocity of Detonation by more than a third. It changes the Detonation Pressure proMe of Detonating Cord to a lower and longer sustained pressure pulse. In addition, it develops more gas than conventional cords. At the same time it maintains all of the handling and reliability advantages of conventional Detonating Cord.

Jan 1, 2001

By D. K. Ingram, G. L. Mowrey, T. R. Rehak

This paper summarizes flyrock and blast area security fatalities from 1989 to 1999 and examines the causative factors. Coal and nonmetal mining used about 43 billion pounds of explosives and blasting agents between1989 to 1999. A majority of this consumption was used at surface mines. Accident data indicates that flyrock and lack of blast area security were the primary causes of blasting related injuries in surface mining. Fatal injuries due to lack of blast area security were attributed to: failure to clear blast area; failure to follow instructions; inadequate guarding; inadequate blasting shelter; and unsafe location.

Jan 1, 2002

By John Watson

Overview: Intro and Product Use Trends ?? Packaged Explosives ?? Bulk Explosives ?? Initiation Systems – Conventional Initiation Systems – Electronic Detonators ??Q&A

Jan 1, 2006

By John A. Franklin, Norbert B. Maerz, D Linn Coursen

Accurate measurement of blast fragmentation is important in mining and quarrying operations, to monitor blasting and optimize blast design. A new digital photoanalytical method to measure the block size is presented here. Photographs of the broken rock are digitized, apparent size distributions measured, and corrections made for overlapping blocks, by means of an empirically derived correction function. The method was tested during recent full-scale blasting tests in Virginia, USA. It shows great potential as a practical aid to predicting, monitoring, and controlling the quality of the fragmented rock.

Jan 1, 1987

By Vaughn Bowns, Allen Stanley, Brian Redeker

"Running casing in drilling operations is often complicated by boulders or large cobbles.Past practices of dealing with these have included use of drop hammers, attempts to drillthrough or around the boulder, contact explosive charges and even pulling the casing andrepositioning the hole. All these methods are time consuming, expensive and offer noguarantee of success. In this paper a different method of dealing with these boulders ispresented that promises to be faster and less expensive with a much higher success rate.This involves using a light plastic conduit pipe to place a shaped explosive against theboulder. It requires no special tools or techniques not commonly in use in the drilling andblasting industry."

Jan 1, 1993

By D. Bartley, R. McClure, W. Reisz

Ever since the 8ms criterion was developed in the early 60’s there has been an ongoing debate among many blasters as to its actual value in controlling ground vibration. The perpetuation of the myth surrounding the 8ms window can be partly attributed to its simplicity and convenience as a means for regulatory compliance. Unfortunately, the mindset that many blasters have adopted has hindered the development and use of more effective techniques and in many cases can actually be counter productive to vibration control.

Jan 1, 2006

By Michael S. Wieland

This report discusses the U.S. Bureau of Mines research regarding the desensitization and malfunction of cap-sensitive explosives deployed in underground coal mines. Delay blasting in underground coal generates severe shock waves and rifting forces that fracture and heave coal. These dynamic interactions can damage other charges still remaining in the delay pattern. The debilitating impacts precipitate degrees of reduced charge performance ranging from misfires to weak detonations or out-of-sequence firings. Damaged charges react poorly, perform less useful work, and/or generate atypical fumes with higher toxicity.

Jan 1, 1993

By T I. Jerman

The Du Pont "Detaline" nonelectric initiation system utilizes a low energy detonating cord. It is compatible with conventional detonating cords and shock tube downlines as well as nonelectric in-the-hole delay caps. "Detaline" millisecond surface and in-hole delays offer a great degree of flexibility in developing effective delay patterns for improved fragmentation and reduced vibration. All components are easily assembled in the field.

Jan 1, 1982

By Ettore Contestabile, Cameron Thomas

Implosive-type electrical/mechanical connectors such as XECONEX have been used extensively for joining electrical transmission lines. This implosive action of explosives has also been applied to other forms of high energy metal working with excellent results. However, as with many other products, the inherent blast energy of these units has caused some environmental concerns especially when used in proximity to inhabited areas.

Jan 1, 1995

By J Edmund Hay, T S. Bajpayee

The Bureau of Mines is developing a test to determine the initiating strength of commercial detonators. Various tests of "detonator strength" are in use, but many of them do not correlate well with each other, and so far, there is little evidence that any of them correlates well with the ability of detonators to initiate detonation in an explosive. Therefore, the Bureau decided to attempt a measurement of the ability of detonators to initiate detonation. To this end, an explosive mixture of adjustable sensitivity was developed. This mixture was nitromethane sensitized with ethylene diamine, the sensitivity being "fine-tuned" by the addition of nitropropane.

Jan 1, 1992