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By Manuel Gutkrrez, Nasslo Gallardo, Arturo Cancec

The study done in Dofia In&s de Collahuasi aims to improve the fragmentation in one of the most difficult rocks to deal with in an operation, It is the Ignimbrita. In order to avoid ejections and to increase the efficiency of the explosive it has been obtained an improvement in the stemming quality by using the Blasting Optimisation Program in Ignimbrita. Different materials were used in the stemming. In 1997 it was used soil material (Paleorrelleno), then in 1999 started the use of crushed gravel and during this year it is being implemented the utilisation of Stemtite only loaded with drill cutting. The first improvement was obtained with the utilisation of gravel, yielding good fragmentation results in comparison with the stemming with detritus material. The stemtite has made easier the blasting operation and it has signiticantly improved the fragmentation.

Jan 1, 2001

By Frank Hirthammer

The paper explains the procedure of implementing Track & Trace solutions for manufacturers of explosives based on customer experiences. By using concrete examples, the process from project start to implementation is described. Lessons learned from the experiences of European explosives manufacturers are presented.

Feb 1, 2020

By Neal Lee

Often the effects of wet boreholes are not taken into consideration when designing a blasting program to exhibit a certain amount of explosive energy per unit of rock such as design by powder factor, expressed in lbs./bcy (pounds explosives per bank cubic yard) or kg/bcm (kilograms per cubic meter), often the effects of wet holes are not considered. This paper examines different methods of loading wet holes and the effects they have on actual explosive quantities/unit of rock. In particular, we are looking at the amount of water trapped within the explosive column (bulk loading from the collar), or the annular space left void of explosives product around and between cartridges (wet-bags) with many of the current wet hole loading methods in use. We will focus on the effect this has on actual powder factor relative to “as designed” dry hole loading values, as well as the effect on performance of the explosives.

Jan 1, 2011

By Robert Hopler

Testing Stations Abroad At the Seventh International Congress of Applied Chemistry, Drs. Mente and Will communicated a paper on the above subject. All large coal-getting countries employ testing stations of some kind, in order to safeguard, to the highest possible extent, the lives of the men employed in this industry. Most countries employ galleries of considerable diameter, and fairly short length; but within recent times, long galleries, with drives and other accessories approaching as closely as possible the actual conditions of mining have been installed. The following are the details of the testing stations employed in the countries mentioned.

Jan 1, 2010

By Randy Wheeler

In recent years the issue of seismograph calibration and accuracy has been a major focal point of the ISEE Blast Vibration and Seismograph Section. In fact, questions concerning the consistency and reliability of seismograph measurements essentially led to the development of this ISEE section. One of the early actions of the section involved the development of “Field Practice Guidelines” for the use of seismographs. These guidelines specifically state that “Placement and coupling of the vibration sensor are the two most important factors to ensure accurate ground vibration recordings.” This paper will address the results obtained from using different coupling methods to record vibration and airblast levels generated from production blasting in a limestone quarry. The data obtained clearly indicate that seismometer burial provides the best coupling for recording ground vibrations. Microphone height has also been an issue regarding the accuracy of recorded airblast levels. The data we obtained indicates that microphone height is not a significant factor.

Jan 1, 2004

By Tom Snyder, John Brulia

PART 3 – UN Identifi cation Markings for the Highway Transportation in Commerce of Bulk Explosives, Oxidizers, and Combustible Liquids

Jan 1, 2015

By John A. Davis, David W. Brunton

(Excerpts, pp 157-160) The usual means of firing blasting charges, especially in tunnels and adits in the Western States, is by the use of a safety fuse. The term safety fuse originated from the fact that when properly used under working conditions this fuse burns at a uniform rate and does not flash or explode, as was often the case with the means employed for igniting blasting charges previous to its invention; but the term is somewhat misleading, because the fuse is not, nor has it ever seriously been claimed to be, safe for use in gaseous coal mines. The fuse used for tunnel work is composed of a core of gunpowder surrounded by various layers of waterproofing material.

Jan 1, 2015

By Daniel Richards, Dr Rob Farnfield, Dr Geoff Adderley

The 8-millisecond rule has been in use for many years as a basic technique to help minimize vibration levels from surface blasting operations. The rule was based on work carried out in the 1960’s by the USBM by recording the vibration levels from a series of test blasts in a quarry over a range of distances. This work included the firing of a series of single hole blasts and a number of single row production blasts using a variety of inter-hole delay times. The delay times employed were limited by the technology available at that time to instantaneous, 9, 17 and 34 milliseconds. There have been several papers in recent years suggesting that the use of the 8-millisecond rule is no longer required, when using electronic detonators, due to their enhanced accuracy and greater initiation pattern design flexibility. This paper examines this proposition by revisiting the original work and employing the linear superposition technique to reprocess some of the original recordings. Similar techniques are then applied to a large database of single hole vibration recordings for a range of rock types, distances, and number of decks, with calculated reinforcements compared to the minimum separations in typical patterns. The results suggest that there is some validity to the 8-millisecond rule when applied to electronic detonators but not in the way it is traditionally applied. Simple guidance is suggested for those designing blasts with electronic detonators to minimize vibration levels even if the benefits of linear superposition trials are not available.

Jan 21, 2025

By Reynold N. Hoover, Davis S. Shatzer

The Bureau of Alcohol, Tobacco and Firearms (ATF) is responsible for the regulation and enforcement of the explosives laws codified in the Organized Crime Control Act of 1970, Title XI. To meet its responsibilities ATF has special agents, inspectors and specialists who regularly interact with the explosives industry. However, with just over 2,000 special agents and 800 inspectors and specialists, it is difficult to visit the almost 10,000 explosives licensees and permittees in the United States.

Jan 1, 1995

By Dyno Nobel

Impact of Enhanced Security on Operations Budgeting - What is the “value” I receive for enhanced security? Is there a “return” for the money I spend? Regulatory driven Economic driven

Jan 1, 2006

By Gordon C. Petersen, Gary A. Almeraris

This paper describes the controlled blasting techniques required to mine a rock tunnel section of a main interceptor located in the Boston Metropolitan area. The 3m (10 ft) x 2.8m (9.25 ft) horseshoe shaped tunnel was driven 490m (1600 ft) by conventional drill and blast methods. The geology varied round by round and consisted of five highly faulted and jointed igneous rock types. The tunnel intersected numerous slickenslides and open mud seams which hampered both drilling and loading operations. Smooth blasting wee critical in order to keep overbreak tc a minimum in this extremely hard but blocky ground.

Jan 1, 1991

By Lance McAnnuff

Whatever system is devised to control noise and ground vibration from blasting operations must present an effective compromise between the rights of the individual to be undisturbed by the actions of others, and the necessity for society, the whole of the population individually and collectively, to have the services and the products of commerce, industry and transportation along with the relaxation of recreational and cultural pursuits, all at a price within the means of the same society. One of the first jurisdictions in North America to attempt to quantify acceptable environmental limits for specific blasting operations was Ontario, Canada’s largest and most populous province. A process for development of guidelines applicable only to quarries and strip-mining operations was begun in 1974 and culminated with their inclusion in a “Model By-Law” published by the Ontario Ministry of the Environment in August 1978. This paper examines the process of development of the final guideline document and its application over the last 25 years. While acknowledging that the published guidelines for air blast and ground vibration control have provided a useful and generally workable framework for the purposes of land use planning and complaint or damage claim reduction, a number of flaws, weaknesses and misinterpretations connected with their application are identified. Recommendations for amendment of the controversial items are submitted with a view to making these and potentially similar guidelines in other jurisdictions, more acceptable to both government and industry.

Jan 1, 2004

By Steve Dillingham

The origin of the written blasting log or shot report can likely be traced back to the earliest annals of blasting and record keeping. These records were, for the most part, a way of checking inventory, production progress, or billing, and not necessarily designed with the intention of being used as a legal document in a court of law. As our litigious society has evolved to include far reaching regulatory requirements, however, the blasting log has developed to support and aid in the defense of the common blaster from blasting lawsuits by providing a comprehensive written report of his or her actions.

Jan 1, 2002

By Norman Paley

A blasting project was undertaken at the Teck Alaska Red Dog Mine in 2005 to 2007 to determine the extent that using electronic detonators could increase Semi-Autogenous Grinding (SAG) mill throughput. The results of that project were reported at the 2010 ISEE Annual Conference. This paper is a postscript to that project and provides the fragmentation resulting from the implementation of a 15% pattern expansion using electronic detonators.

Jan 1, 2012

By Rob Grant, Manuel Lopez Cano, Mike Briggs, Ken Fletcher

The scorched desert sands and life giving waters of the River Nile in Egypt have been the back drop to awe inspiring engineering feats for over 4,700 years. The latest engineering marvel to grace the land of the Pharaohs is the Mubarak Pumping Station Project at Toshka. This ambitious project aims to open up an area of 607,000 hectares (1.5 million acres) of barren desert to irrigation based farming with the supply of 29 million tonnes (32 million tons) of water per day, drawn from Lake Nasser on the river Nile. It is anticipated that this currently unpopulated area of southern Egypt will soon flourish and become home to several million Egyptians who will conduct their lives around the water supplied by the 230 kilometers (144 miles) of concrete canals. An integral part of the pumping station is the intake canal. The canal was excavated in two sections – the dry excavation, and the wet excavation. The wet excavation comprised of some 5.5 million cubic meters (7.2 million cubic yards) of rock to be drilled, blasted, and excavated, from the surface of the lake. The challenge at hand was how to achieve this safely, quickly, and cost effectively, with water depths of up to 45 meters (148 feet), excavation depths of up to 47 meters (154 feet), blast production rate peaks of up to 30,000 bank cubic meters (39,200 bank cubic yards) per day, blistering summer air temperatures up to 60°C (140°F), and security concerns about the storage of large quantities of explosives in the Middle East region. The solutions to these challenges were engineered by UEE Explosives and centered around the use of a microgel bulk explosive called Rioflex™ and an international team of engineers and operators from three continents. The microgel and accompanying pumping system allowed pumping rates of up to 17,400 kg (38,400 lb) per day, and more importantly, enabled the bulk product to remain as an oxidizing matrix whilst in transport and storage, transforming into an explosive only moments before being pumped into the blastholes. This case study outlines the underwater drill and blast process employed at the Mubarak Pumping Station Project at Toshka, and the novel solutions to the unique challenges encountered.

Jan 1, 2004

By D. Lynn Gordon, Larry B. Weston, Michael W. Manhart, Patrick R. Bowden, Michael W. Redmond

Study of confinement effects on detonation characteristics and subsequent fitting form development as a function of confiner strength and thickness.

Feb 1, 2020

By Clarence Hall, Charles E. Monroe

Squibs, Fuse, and Detonators It has been made clear in the discussion of combustion and explosion and the description of various explosives that they can be caused to explode by various means. All of them can, under some circumstances, be made to explode by fire. Some of them can be caused to undergo a detonating explosion by setting off a detonator in contact with them. In blasting use is made of both these means for setting off explosives, the means used being determined by circumstances.

Jan 1, 2010

By Soseol Kim

A high-performance Emulsion-based booster explosives has been developed that can be used as a booster for bulk explosives. Currently, Pentolite booster, which is mainly used as a booster for bulk explosives, has a high risk of accidents due to the sensitivity of its raw materials PETN and TNT, and has a low melting point, making it impossible to use it in high-temperature ground. The Emulsion-based booster was developed to maximize the Velocity of Detonation (VOD) while elimination the shortcomings of the Pentolite booster. The VOD of the Emulsion-based booster is about 6,500m/s, so it can maximize the performance of the bulk explosive. In addition, it can be used in high-temperature ground and does not cause accidental detonation due to the external environment. In this article, the performance of the Emulsion booster was verifies through comparative test blasting of the developed Emulsion-based booster and Pentolite booster.

Feb 6, 2023

By Laurence Neufville

Proper risk assessment and blast design are very desirable to the execution of a blast. Not only will this ensure that it achieves its desired outcome, but the probability of complaints and litigation will be reduced. Blasting engineers rely heavily on site-specific data for analysis and input to the blast design equations, and therefore data collection is critical to this process. The traditional approach to data collection is to carry out site-specific reconnaissance by visiting the site, but the time spent doing so can be reduced if a remote sensing approached is adopted.

Jan 1, 2009

By Dale S. Preece, Ruilin Yang

Shock wave physics is an important part of air-deck behavior since the bulk explosives in the column impart a shock into the air-deck where the air shock then passes through the air-deck at a rapidly attenuating velocity. Through both high-fidelity modeling and shock physics theory it is shown that the resulting pressure in the air-deck is two orders of magnitude less than the detonation pressure of the explosive. The induced air blast reflects from the bottom of the borehole and this reflected pressure, even though doubled, is still approximately two orders of magnitude less than the detonation pressure. Air-shocks will ring back and forth in the air-deck for a few tens of milliseconds while the adjacent explosive column(s) are detonating. Transmission of the initial shock through the air along with reflections is an intensive energy consuming process. Energy balance results in shock heating of the air and a temperature increase. However, the increased temperature of the air is also orders of magnitude less than that of the explosive detonation products immediately behind the detonation front. Replacing high energy explosives with zero energy air-decks in a blasthole will always have a negative impact on the adjacent rock fragmentation and movement.

Jan 1, 2016