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By R. K. Wharton

A European Directive requires that an explosive which is sold or transported within Europe must meet certain essential safety requirements from 1 January 2003. The assessment and certification of such an explosive is undertaken by an Explosives Notified Body and if the explosive meets the requirements a certificate is issued that allows the affixation of a CE mark. The presence of a CE mark ensures the product free access to European markets. The paper examines the requirements of the Directive, identifies those explosives that come within its scope, considers the role of an Explosives Notified Body, and explains the process of applying for certification.

Jan 1, 2002

By Chantale Doucet, Mario Paventi, Malcolm Scoble, Yves Lizotte

Laboratory studies in homogeneous material indicate that the area of new surfaces created by blasting is proportional to the energy imparted to the material. Field studies, however, show that fragmentation is also related to the rockmass structure. This paper reviews ongoing compilation of a comprehensive and integrated blasting database which is based upon field monitoring and laboratory testing. A priority application of the database is to support attempts to more fully understand structural control over fragmentation. Database construction and the relative importance of rockmass physical and mechanical properties are considered in the paper. A methodology for data collection prior to, during and after blasting is reviewed. Data summaries from three case studies of blast performance in surface and underground mines are presented. These illustrate various aspects of the methodology, which included image analysis to quantify the fragment shape and remnant geology evident in the muckpile as part of the evaluation of structural control over fragmentation.

Jan 1, 1994

By Jonathan Heiner

Rio Tinto Bingham Canyon Mine started its South Wall Push Back (SPB) in 2011. This push back will mine through the only road to the pit bottom (the 10%). The pit bottom is the main ore sector for the mine and supplies about 80 to 90% of the ore. In late 2017 the mine set off a blast in SPB that created a small wedge failure on the high wall between SPB and the 10%. This wedge failure released a rock approximately 20 minutes after that blast that rolled down the wall landing on the 10% near and then contacting a light vehicle

Jan 1, 2019

By Charles Zdazinsky

Many blasting applications in the mining industry demand that the hard rock being blasted remains structurally competent. For example, pre-splitting is a common technique to reduce fracturing, and operators of dimension stone quarries use this blasting method to eliminate overbreak. When pre-split design parameters are not applied correctly, there will be a redistribution of stresses within the rock, resulting in Blast Induced Rock Damage (BID). Advances in geophysical technology are enabling blast technicians to monitor BID and then use the results to correctly design their blasts.

Jan 1, 2011

By Jorge Cárdenas, Luis Huaroc, Máximo Cari, Nestor Delgado

In Peru, after four years of pandemic, some mining companies have chosen to install integrated operating centers in central offices where through network technology and video surveillance it allows them to carry out their activities remotely, this has become a disruptive strategy to promote a safer and smarter mining industry. Our fundamental value is to improve the quality of life, safety and well being of our collaborators, that is why we have created the remote blasting engineering control center " Core" that allows us to humanize mining. Core is an integration of experience, security, technology, quality of life and artificial intelligence; it has media technology connected directly to the mining operation, specialist engineers and technical assistants in team they seek to create optimal proposals of drilling and blasting designs remotely that generate added value to customers. In the planning process the team suggests drilling meshes, in the loading process there are optimized, digitized designs and efficiency in the factory trucks finally in the safety process allows us to identify inadequate pipes within the blasting project, deviation of procedures, remote inspections, identify operating conditions to prevent future risks that may arise in the blasting process. The remote communication systems allow you to monitor mining operations remotely to identify and alert any operational or security deviation that was not identified by the personnel present in the operation, as well as to store images in case investigations are required. The results obtained have allowed us to reduce the exposure of personnel to any risk of the mining operation, to optimize times in the activities of our engineers who are in the mining operations since there is the permanent support of centralized specialists to face every challenge that arises in the operation, for the engineers who are in the offices of Core can be very close to the family and do not lose it, and for our customers it is to meet their needs with engineers specialists in the drilling and blasting process, as well as in safety to be able to proactively cope with any deviation that arises.

Jan 21, 2025

By Steve Dillingham

With the millennium fever all but faded, we look to a new century filled with awe and excitement. We step forward in time, marveling over the achievements of the 20th century and wondering what the next 100 years could possibly bring. Will there ever be another time that produces such technological advances, economic progress or social changes? Keeping pace with the awesome accomplishments of the past century has not been an easy task and we must prepare ourselves for the possibilities of the future. Take, blasting safety for instance. We all know that safety is personal - a culture - promulgated not only by the company by which you are employed, but, by a sense of your own personal responsibility that must constantly be reinforced through awareness, training, and discipline. Great strides have been made in blasting safety since its crude beginnings, however, safety consciousness becomes even more important as technological advances and scientific progress are made in the coming years. It all begins with a positive safety attitude where every employee habitually examines each situation encountered, identifies potential hazards, and takes precautions to avoid those hazards.

Jan 1, 2002

By Dr. Tristan Worsey, Dr. Jhon Silva-Castro

Confinement is an important aspect of blasting. Reducing and increasing confinement can determine whether a blast design performs properly. Over-confined shots usually have poor fragmentation, higher vibrations, and stemming ejection, and unconfined shots usually have a lot of air blast and fly rock. When talking about confinement in blasting, static confinement conditions are typically referenced. Static confinement conditions are ruled by free faces, shot muck, burden, spacing, stemming, hole depth, toe, etc. All these conditions exist in a static state. Static confinement conditions are generally analyzed before the shot takes place, but once the shot starts, the conditions will change according to the sequence and delay of the shot. Once the shot starts, Dynamic confinement takes place. For the authors, Dynamic confinement is the confinement conditions that exist for the charge when it fires and should account not only for the variables included for the static confinement but also for the time and sequence of the shot. The paper explores the theory of dynamic confinement and its role in influencing blast performance. Time and sequence are the main influencers of dynamic confinement and will be the focus of the paper. How to generate the appropriate timing based on blast design, dynamic confinement, static confinement, and geology will also be discussed.

Jan 21, 2025

By Joe Sr Strobbe

In 1933 the Cobre Mining Company re-opened the 32-year-old UV Industry Mine, which is located in a scenic canyon near Silver City, New Mexico. The site location is shown in Figure 1. Current mineral extractions are copper and magnetite; both extractions similar to those mined many years ago. Copper is extracted from chalcopyrite imbedded in the host rock of massive limestone deposits and magnetite, an iron ore, is a by-product of the same extraction process.

Jan 1, 1998

By Art Frye, Lee Pratt, Gaichang Zhao, Greg Newman

This paper will discuss the Wight Pit wall slash at the Mount Polley open-pit copper-gold mine that scavenged a high grade block of ore from two double-benches of the pit wall. The Wight Pit orebody, discovered in 2003, is located in the Northeast of the property with the southeast pit wall approximately 50m (165ft) from the edge of Polley Lake. In early 2009, the Wight Pit was nearing completion while an estimated 150,000 tonnes (165,000 tons) of ore averaging a grade of 1.4% copper remained just inside the southeast pit wall. The ore block started 24m (78ft) above the pit floor and extended up another 48m (157ft) with a 70o plane defining the back of the block.

Jan 1, 2011

By M. Syafiq Isnaya, Rahma Norfaeda, Slamet Rachman Jaka

This paper is about project improvement to maximize energy distribution while ensuring beneficial blast results (reduce boulder condition). The main problem is how to manage complex lithology conditions related to detonation propagation in energy distribution control.

Feb 1, 2020

By Bengt Ljung

Manual charging of long upward drilled holes in mines is a heavy and risky job today. Mechanization of this work has been requested for some time by miners, their supervisors, industrial safety organizations and the trade unions, all of whom are interested in improving the working environment. This paper presents newly-developed charging systems intended primarily for charging in connection with sublevel caving and sloping. These systems have been field-tested during 1977 in the LKAB mines in northern Sweden. The results of these field tests and the results of laboratory work conducted to help eliminate the risks involved in charging explosives are also discussed. The equipment being tested (see fig. 1 and 2) consists of a charging vehicle with articulated steering, the PT-60, which has been equipped with a hose feed system mounted on the hydraulic extension boom. From a sheltered position, the operator brings the detonator and primer to the hole opening, after which the hose is pushed in mechanically to the end of the hole. Measuring equipment indicates when and if the end of the blasthole is reached. The operator then withdraws the hose mechanically as charging takes place.

Jan 1, 1978

By Rajesh Sonkar, Sanjeev Kumar

The deployment of Dragline machines in opencast coal projects involves huge capital expenditure as well as operating costs. The mine operators always endeavor to ensure smooth excavation of material by the Dragline machines while meeting the major objectives of safety, minimal disturbance to environment and optimal operating costs. Optimization of fragmentation through well designed blasts is fundamental in meeting part of the objectives is good fragmentation of rock or mineral proposed to be lifted by the Dragline machine. If the overburden lying over mineral is not properly fragmented, it may result in formation of ‘Toe’ the removal of which is the most arduous task in opencast coal mines. The mine operators always endeavor to achieve best possible results in blasting to ensure smooth operation of the high cost Dragline Machine. However, despite continuous efforts by the blasting engineers involved in bench blasting for the machine, the formation of ‘Toe’ is an ever nagging problem faced in large opencast coal projects eventually reducing the overall operational efficiency of mining.

Jan 1, 2011

By U Nyberg

Peak particle velocity (PPV) and distance measurements from a single-charge blast test conducted by Swedish researchers in iron ore at the Kiruna Mine in northern Sweden are presented. They are used along with theoretical PPVs calculated using an equation based on hydrodynamics to determine a damage distance range caused by a single charge. This equation, which relates PPV to explosive properties, charge geometry, and distance from a charge, was then applied to a charge of different geometry that was used in drift rounds. A comparison between calculated and measured PPVs suggests that the stoping holes likely damage the easer hole locations, and the easer holes produce damage to the perimeter hole locations. The practical effect is that typical damage limit predictions based on measurements conducted in fresh or undamaged rock are conservative. This suggests that even when perimeter control is not exercised in drifting (i.e., the perimeter holes are fully loaded), the resulting damage may be less than normally expected due to the wave damping effect of the pre-damaged rock. Due to the damping effect, poor perimeter blasting practices are somewhat self correcting. However, it must be strongly emphasized that well-engineered blast designs with perimeter control are highly beneficial in relation to both economic and safety aspects.

Jan 1, 2011

By M. Szumny, P. Mertuszka, K. Fuławka

Multi-face destress blasting is the basic method of reducing rock bursts hazard in Polish copper mines. Blasting operations of this type are carried out regularly, twice a day in order to minimize the geomechanical threat while maintaining high extraction efficiency. Unfortunately, the assessment of the effectiveness of this type of work until recently was based solely on determining whether a given destress blasting triggered a seismic tremor or not. Information on the characteristics of seismic waves generated by blasting has so far been omitted in analyzes of this type. The lack of reliable knowledge about the generated seismic effect makes the introduction of constructive corrective actions impossible, which in turn significantly reduces the triggering potential of conducted destress blasting. This study presents the results of comprehensive work aimed at increasing the effectiveness of active rock burst prevention in Lubin underground copper mine. For this purpose, an innovative system for continuous monitoring of seismic waves induced by multi-face blasting was developed, and a new method for seismic assessment of the effectiveness of the destress activities was developed. Based on the monitoring data and the comprehensive analysis of waveforms, the effectiveness of individual blasting operations was determined, and on this basis, modifications to the drilling and blasting patterns aimed at increasing the generated seismic effect were proposed. The use of innovative methods of monitoring and data analysis made it possible to increase the effectiveness of the conducted activities, in terms of the magnitude of seismic vibrations, up to 250%. It should be emphasized that the introduced modifications were aimed at increasing the effectiveness of blasting operations while maintaining the current level of costs. As a result, the proposed solution turned out to be highly effective, significantly affecting the safety of the work carried out in Polish copper mines. Thus the proposed approach is planned to be implemented in other Polish copper mines belonging to KGHM in the near future

Jan 1, 2024

By Lewis L. Oriard

The purpose of this paper is to provide an overview of close-in blasting effects on various types of structures and building materials, as encountered in this writer's professional practice. Structures range from old, deteriorated historical monuments to new, heavily reinforced buildings. Materials range from clay adobe to concrete and steel. Site locations range from tropical to arctic. Blasting ranges from sculpture blasting inside buildings to "coyote" blasting and large surface blasting operations. Space limitations permit a brief discussion of only 25-30 specific cases, but they have been selected to be typical of conditions found on hundreds of similar cases. The writer was asked to present a discussion of representative cases where relatively high vibration intensities were experienced. Virtually all of these cases were free of damage, but the few damage cases provide valuable insight to the mechanisms involved. Observations of such damage and non-damage cases have served as the basis of this writer's criteria for various structures and materials, as well as the technology to conduct blasting operations within those criteria. A sampling of these experiences is gladly shared with the reader.

Jan 1, 1991

By Eric Roller, Elliott Giles

All flyrock incidents have the potential to result in injuries or fatalities that can result in loss of company reputation, license to operate with clients, and bear the exposure to high cost liability. From 2007 to 2009,one NA Quarry and Construction Business experienced a series of flyrock incidents. In the spring of 2009, this business declared that the frequency and severity of Flyrock Incidents had reached an unacceptable level. A Flyrock Elimination Program was launched.

Jan 1, 2012

By Tuan Nguyen, Dirk Hummel, Ruilin Yang

In a tunnelling site in Japan, it was found that detonators failed to initiate with their shells and primary explosive intact. Their capacitors, however, were discharged due to some damage on the application-specific integrated circuits (ASICs). These detonators are distinctly different from other commonly observed failures, where the shells are rather crashed due to excessive dynamic pressure received from neighbouring blastholes which fired earlier. Such incident has not been reported elsewhere. Detonator failures during a blast are deemed not safe and can cause disruption on the project productivity. It is therefore desirable to understand the origin of such event. Various measurements were conducted to diagnose the problem, but the root cause had yet to be identified. This paper applies a discovery from a 60-year-prior-laboratory experiment and formulates a theory that could explain the observed detonator failure and predicts the measurements and observations.

Feb 6, 2023

By Gungor Tuncer, Ali Kahriman, Abdulkadir Karadogan, Simav Bargu, Savas Gorgun, Derya Kucukbrtem, Esat Tansev

Although many research studies had been carried out in the past in order to eliminate environmental issues produced from blasting unfortunately a general approach or formula has not been established yet because of the complexity of the matter. In addition to the wave and ground motion characteristics, the complexity of blasting parameters and site factors restrict the developing of a general criterion. So experimental site-specific studies should be still done in order to predict and control blasting effects.

Jan 1, 2002

By Robert J. Nothnagle, Kristen Franz Begor, Rodney W. Sutch

Recovery of contaminated groundwater in a fractured bedrock system presents some unique problems. Typically, the most common problem occurs from the inability to adequately characterize the discrete fractures through which contaminants may be migrating. Without adequate characterization, difficulties arise in properly positioning recovery wells and verifying the performance of the system. To overcome these difficulties at a site in Upstate New York, an innovative approach was developed involving the creation of an artificial fracture zone through controlled blasting to intercept contaminated groundwater flow.

Jan 1, 1988

By Hans Florin

This paper describes the modification of a nonelectric detonator which is ignited by a signal tubing. The heart of the new detonator lies in a so-called ignition transmitting element. The construction of the transmitting element is such that the detonator remains closed even after the signal tube has functioned. Due to the sealing of the delay element, this nonelectric detonator achieves the same accurate delay timing as high tech delay electric detonators and will not fail due to a sudden pressure loss.

Jan 1, 1988