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By Mike Higgins

"The purpose of mining and its related industries is the removal of, and usually the subsequentprocessing of, material from the earth. This includes mining for minerals, quarrying for stone, and civilexcavations. Where this involves rock, the most common method is to fragment the rock by blasting. "

Jan 1, 1997

By David G. Borg, John Bussey

The new AIRDEK (tm) technique for pre-splitting in surface coal mines produces highwall conditions that have greater safety with lower costs for explosives, labor, and drilling. Successful applications have been made in highwalls ranging from 20 to 100 feet or more and in blasthole diameters from 3-1/2 inches to 12 inches.

Jan 1, 1988

By Fred Baldassare, Marcia Harris, Kenneth K. Eltschlager

Surface mine blasting was recently investigated as a potential source of high concentrations of stray gases found in nearby residences of western Pennsylvania. In one incident carbon monoxide was detected in a home and in the other, high concentrations of carbon dioxide were found in a home. Both carbon monoxide and carbon dioxide are by-products of blasting. However, other potential sources of these gases may also exist in a residential setting. In each case, gas chromatography (GC) and carbon isotopic analyses were used to define atmospheric concentrations inside the homes, and to determine the source of a stray gas. Molecular and isotopic analyses provide geochemical evidence as to the origin and source of the stray gas. This paper discusses elements of a stray gas investigation and the analyses necessary to identify the source of a stray gas.

Jan 1, 2004

By Joshua Hoffman, Braden Lusk, John Rathbun

A Flyrock Prevention Taskforce was established in Kentucky with the support of Kentucky's Department of Natural Resources, Kentucky's Explosives Industry, and the University of Kentucky. This paper presents the initial work of the Flyrock Prevention Taskforce towards its missions of identifying the root causes of flyrock incidents based on the analysis of previous events, and tracking the progress of flyrock elimination in the future. Work identifying root causes of flyrock events is presented through the development of a database which manages information about the blasts which caused flyrock. This data includes: blasting and seismograph records, drill logs, videos of the event when available, company notes/incident reports, and any additional information regarding probable cause. Work tracking the progression of flyrock elimination efforts is presented in this paper through the introduction of a flyrock index. Several metrics are proposed for this index, and are discussed for their appropriateness and shortcomings. In order for these indexes to be valid forms of tracking flyrock incident rates additional records must be kept and reported, such as the annual consumption of explosives by surface coal blasting. Suggestions for record keeping, flyrock investigation practices, and means of tracking flyrock incident rates are proposed in this paper.

Jan 1, 2013

By Richard E. Danell

"There are a variety of approaches for wall control blasting in open pit mining operations. Safety forworking in the pit is the principal benefit. There are also a number of economic and productivitybenefits when appropriate techniques are used. The purpose and requirements of wall control blasting can vary quite significantly for different operations. When considering blast design, geology, geotechnical factors, drilling, explosives, economics and blasting history are all part of the engineering design process. In many operations, there is a high reliance on blasting history and economics for determining wall control blasting measures. This presentation outlines approaches that broaden the design process and discusses their advantages."

Jan 1, 1997

By E. Contestabile, R. von Rosen, R. Guilbeault, R. Fouchard, P. Lightfoot

In August 1998, a truck loaded with 18 tons of blasting explosives, including over 13 tons of ANFO, left the road near Walden, Ontario. The crash caused a fire; approximately 30 minutes later a large detonation occurred, causing substantial damage to the roadway and local property. Although nobody was injured in the explosion, the consequences of a similar incident in a heavily populated area could have been catastrophic. Following the Walden incident, Transport Canada and Natural Resources Canada embarked on an extensive experimental program to determine the cause of the detonation. This paper describes part of that experimental program, designed to understand better the thermal decomposition of ANFO.

Jan 1, 2003

By B. Winterberg, C. Lewis, M. Starkel, C. Johnson

Non-electric systems, specifically shock tube, have become the pyrotechnic detonator of choice over electric due to their safety regarding accidental initiation from stray radio signals. Typically, the best practice when hooking up shock tube systems is to have direct contact to ensure initiation. When gaps are introduced to the explosives chain, there is potential for detonation to come to a halt. It is understood that direct coupling is required between the various elements in the explosive chain to ensure detonation. This holds true whether tying in non-electric detonators, loading holes in a mining related blast, or priming a block of C-4. Poor contact and gaps in the explosives chain can lead to detonators firing out sequence, leading to increased vibration, air overpressure, and other undesirable blast results. Furthering work conducted in previous experimentation, a new study was conducted at the Missouri University of Science and Technology’s Experimental Mine in Rolla, Missouri to observe the initiation potential of an air gap and fragmentation on non-electric shock tube. A series of small test blasts were conducted using 50 grain detonating cord and fragments from a blasting cap to initiate a non-electric shock tube across an air gap of varying distances. The data collected in the high-speed imagery was used to analyze the velocity of the pressure fronts and blasting cap fragments used to initiate non-electric shock tubes across an air gap. It was found that the shock tube was sensitive to 50 grain det cord at a 5cm (1.97in) distance while parallel and 10cm (3.94in) when perpendicular as well as sensitive to frag from the electric cap out to 2.4m (7.87ft).

Jan 1, 2024

By Timothy Stark

At present blasters are strictly liable under tort law for personal injury and property damage caused by ground vibrations and/or air overpressures. The application of strict tort liability to vibration and air overpressure damage has resulted in litigation that has hampered and probably will continue to hamper the blasting industry. There are many case histories in which blasters have been sued for the appearance of cosmetic cracking, some of which have involved frivolous claims and marginal expert testimony (Oriard 1999). This litigation has resulted in additional costs to the blasting and construction industries and the American public because there are usually many plaintiffs involved and each case is usually adjudicated separately instead of under a class-action format. It is proposed herein that blasters not be held liable for vibration or air overpressure damages unless their conduct is proven to be negligent. A number of reasons are presented for raising the legal standard from strict liability to negligence including: (1) improvements in blasting technology that allow blasting to be conducted without substantial risk of damage and if damage does occur it is likely to be cosmetic, (2) establishment of conservative ground vibration and air overpressure damage limits for typical structures, and (3) established industry standards for construction blasting.

Jan 1, 2002

By Thierry Bernhard, Johan Finsteen, Charles Dowding, Mathias Jern

To bring some clarity to how different standards relate to each other a project was initiated within the European Federation of Explosives Engineers (EFEE). The first part of the project was a literature study and a survey including an evaluation of the answers provided by members of EFEE. The results were presented at the International Society of Explosives Engineers (ISEE) conference in Denver 2020 as well as the EFEE conference in Helsinki in 2019.

Feb 1, 2020

By David Cole, Paul Cooper, Dale Preece, Jerome Stofleth

The Explosive Destruction System (EDS) has been designed at Sandia National Laboratories for the disposal of chemical munitions (phosgene, mustard gas, sarin etc.), many dating back to World War I. EDS is a portable system that is trailer mounted and consists of a vessel into which a chemical munition can be loaded and opened for neutralization with linear and conical shaped charges. Gases are contained within the sealed chamber. The linear shaped charges split the munition in two and the conical shaped charge (CSC) is aimed at the explosive burster, in each munition, which is detonated by the resulting shaped charge jet, Toxic chemicals remaining in the vessel following detonation are neutralized and disposed of. This paper documents the development of a new CSC needed to reliably detonate explosive bursters in an expanding array of chemical munitions that are beyond what the EDS device was originally designed to eutralize. Design of this new CSC was controlled by the need to deliver energy above the detonation threshold into the explosive after penetrating the outer steel casing, fluid, the burster casing and finally the explosive. Design considerations were driven by jet conditions at the steel/explosive interface inside the burster. Parameters to consider in CSC design include: 1) diameter, 2) liner thickness, 3) liner position in body, 4) explosive weight, and 5) liner shape or interior (apex) angle. The effects of these parameters on final CSC performance are examined in detail. CSC’s that meet the design specifications have been manufactured and tested. The performance of these charges are compared with the original design requirements.

Jan 1, 2002

By Jeffrey L. Dean

Now in its twenty-fifth year, the ISEE has grown to more than 4000 members representing 75 countries. The Society and its 35 chapters in the US, Canada and Australia work to educate the public about our industry, provide forums for the exchange of explosives technology, serve as a repository of explosives information, offer expert help to governments, develop standardized methods and terminology, and promote research and education by, creating and conducting certificate and trainktg programs and encouraging the teaching of the safe and controlled use of commercial explosives.

Jan 1, 1998

By William Reisz

Many different types of drills coming in a wide range of sizes and configurations are used in the blasting industry today. While each system may have its own unique attributes and capabilities, it may hold its own perils as well. This article will focus primarily on hazards that are mutual to most every type of drilling system.

Jan 1, 2013

By Catherine Johnson, Barbara Rutter, Phillip Mulligan

Shock tubes, shock tunnels, and blast tubes have been widely used by explosive researchers and shock wave investigators to understand the characteristics of shock waves. Rectangular, cylindrical, and conical are the three simple geometries commonly used in shock tube and shock tunnel testing. These geometries result in shock waves that resemble the Friedlander curve’s simple exponential decay. However, geometries that are more complex have not been studied. This research investigates how changes in shock tunnel geometry affect the pressure versus time waveform. The Large Arena Test Simulator (LATS), which is composed of four different rectangular sections connected by three expansion sections, was used to determine how the changes in geometry affect the shock wave profile. Shock wave profiles were measured inside and outside the LATS to investigate the geometry’s effect. A representative shock wave profile from each geometry and open-air explosive testing were compared visually showing the geometries effect on the shock wave profile. The LATS produced a waveform with four pressure peaks behind the initial shock front, which were found to be associated with the four rectangular sections. The resulting pressure trace was compared to pressure traces from simulated urban bombings. The number of turns in an urban environment equated to a new peak, which is caused by additional expansion sections of the shock tunnel. From this observation, complex geometry shock tunnels can be purpose built to simulate an explosion in an urban setting. The use of shock tunnels with complex geometry in simulating urban bombings can allow for numerous representations and a better understanding of profiles produced during an urban bombing or similar scenario.

By T. Palangio

Most blasters wouldn’t think of initiating a shot without a seismograph to record vibration and air blast results. Some might even measure the velocity of detonation but few surprisingly record the event on video, photo document loading conditions or take pictures before and after the shot. This paper discusses digital imaging, the equipment, methods, techniques and information that can be learned from digital pictures taken in the field during blasting operations. The guy who said “a picture is worth a thousand words” probably understated it.

Jan 1, 2008

By Roger Holmberg, Donald Jonson

The Swedish Standard SS 460 48 66, “Vibration and shock - guidance levels for blasting induced vibration limits”, is based on more than 50 years of experience from blasting close to structures and tunnels. The Swedish Standard gives a method for calculation of guidance values for different types of buildings and ground condition under the building. This is done for every building and structure within a predetermined zone. The guidance levels are for the peak particle velocity monitored in vertical direction. The standard is valid for all kinds of blasting project (tunnelling, quarrying, mining etc.) The guidance levels neither take in to consideration discomfort for people inside the building or structure nor vibration sensitive equipment inside the structure. The paper also presents the Swedish Standard SS 02521 “Vibration and shock - Blast induced airborne shock wave - Guidance levels for buildings”.

Jan 1, 2005

By Ron Beeslaar, Tony Rorke

The Professional Blast Manager is a blast design tool that has been developed in South Africa. It is aimed at mining and civil engineen, blasting contractors and mine planning engineers. The code can be used as a stand-alone package or be combined Into complex mine information systems.

Jan 1, 1998

By Barbara Rutter, Phillip Mulligan

This research investigates how changes in shock tunnel geometry affect the pressure versus time waveform. The Large Arena Test Simulator (LATS), which is composed of four different rectangular sections connected by three expansion sections, was used to determine how the changes in geometry affect the shock wave profile.

Feb 1, 2020

"The objective in controlled blasting is to reduce overbreak to control the final pit wall slope, shaft, drift ditch, bench, etc. to the final planned excavation limit. The six main types of controlled blasting utilized today are:1. Line Drilling2. Cushion Blasting3. Smooth Wall Blasting4. Buffer Blasting5. Presplitting or Preshearing6. Air Deck Presplitting"

Jan 1, 1994

By Richard L. Ash

A question that frequently arises during litigation concerned with accidents or alleged damages involving blasting is "were the explosives used according to the best known standards"" The question is not confined to only law suits, however, but also everytime poor blasting results occur. Unfortunately, general guidelines that can be used to define what may be considered as proper practice have not been established by any responsible body upon which to base a reliable Judgment; more often than not decisions are made primarily according to personal opinion.

Jan 1, 1975

By Robert C. Fouchard, Gordon Chalmers, David E. G. Jones, Ivana Alilovic, Phillip D. Lightfoot

There have been numerous international instances over the last several years in which pumping emulsion explosives has resulted in accidents, apparently as a result of increased thermal sensitivity under these conditions. The key questions for the explosive industry are (1) what are the parameters that influence the sensitivity of emulsion explosives and, (2) how do these various parameters interact. To address the sensitivity of emulsion explosives to various parameters, a study was undertaken using an accelerating rate calorimeter (ARC) and a heat flux calorimeter (HFC). The effects ofthe addition of ammonium nitrate (AN) prills and different grades of aluminum (Al) on the thermal behaviour of emulsion explosives were determined. Additionally, changes in pressure, atmosphere (inert or oxidizing) and sample vessel material were assessed for their impact on thermal sensitivity. Addition of AN prills, fine granular Al or atomized Al did not affect the onset temperature for exothermic decomposition, so that the maximum “safe” temperatures for emulsions containing these additives will be similar. There were differences in the rates of self heating, however: AN prills decreased the rate of self heating, whereas atomized Al increased it. The emulsion formulations containing atomized Al produced small holes in titanium vessels. This phenomenon did not occur in Hastelloy C vessels, providing a reminder that materials of construction need to be carefully considered for equipment used to manufacture or handle emulsion explosives.. Both ARC and HFC experiments gave lower onset temperatures in air than in argon. We attribute this to oxidation of the oil phase by air. This result is significant for dry-running pumping conditions, where emulsion is heated in the presence of excess air.

Jan 1, 2000