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According to the Directive 93/15/EEC, given on 5th of April 1993, all the commercial explosives placed on the market and transfered in European Union and EFTA countries have to be certified and contain the CE-marking. Before the products can be awarded by the CE-marking they have to fulfil the Essential Safety Requirements (ESR) of Appendix 1 of the Directive. From the beginning of last year the commercial explosives could not have been be sold in Europian Union countries without the CE-marking. The legitimacy of the Directive 93/15/EEC encompasses High Explosives, Detonating Cords, Safety Fuses, Gun Propellants and Detonators. At the moment in Europe, there are seven Notified Bodies (NB) working in the field of commercial explosives. They are in Spain (LOM), Germany (BAM), France (INERES), England (HSL), Netherlands (TNO-PML), Sweden (SP) and in Finland (PvTT). The Swedish SP has qualifications only for the detonators and the Finnish PvTT for High explosives, Detonating cords, Safety Fuses and Gun Propellants, but not for the detonators. The role of the NB is to work as a third independent body between the client and the manufacturer testing, studying and certifying explosives by the commission of the manufacturer. The Notified Bodies are operating independently competing the clients, the explosives manufactures.

Jan 1, 2004

By S. Lim, G. Walsh, V. Romero

The cable television show, Mythbusters, contacted the New Mexico Institute of Mining and Technology requesting a pressure gauge to be used in underwater testing. The requirements for the gauge were: it must be passive (i.e. require no power to function), it must indicate when a certain, pre-determined pressure was reached, and that indication was to be visual. A pressure gauge was developed, using standard, commercially available rupture discs, set to burst at 500 psi. Underwater testing was conducted using a 400 lb Pentolite charge. Test devices were set out at ranges from 50 to 200 feet from the seat of the blast. The rupture discs showed a lethal range up to 100 feet, but not at 150 feet. This result matched well with the behavior predicted through modeling and simple shock physics calculations. Additionally, the geometry between the incoming shock and the pressure gauge did not seem to have a strong effect on gauge performance.

Jan 1, 2009

By Paul Schmiesing, Matt Higgins

Central Oregon is a fast growing resort community centered in Bend, Oregon. Bend is bordered by the Cascade Mountains to the west and the high dessert to the east. Central Oregon is blanketed with lava rock with little topsoil. Ditch blasting is a staple in the area. Almost all utilities excavation (gas lines, sewer lines, water lines, and electrical lines) requires blasting. There is also a considerable amount of blasting required for site excavations and drywells. On average, there are over 500 blasts per year in Bend alone. All of this blasting is done using small holes, generally 2.5 inches in diameter. Typical ditches will have 200 holes, between 2-3 rows wide, with an average depth of 8 feet, and on 36 inch centers. Almost all shots are dry. Successful blasting requires careful control of drilling and loading. The vesicular basalt contains numerous lava tubes and caves making drilling and loading difficult. The rock conditions vary greatly from one side of town to the other requiring different powder factors and different scale of distances for vibration control. Caret%1 calculations of vibration predictions and use of site-specific seismic info is necessary. Marry shots will require deck loading and careful timing to ensure one-charge per delay. It is an every day occurrence to be blasting near residential and commercial structures or high pressure gas lines. Many times ditch blasting will incorporate excavation blasting. The different hole patterns used for the ditches and the excavation shots presents challenging timing sequences.

Jan 1, 2000

By Ravi Sahu, Kris Jeremiah

This paper aims to study the benefits of using Post Processed Kinematics(PPK) surveying methodology combined with Drone photogrammetry to achieve highly precise positioning (X, Y, Z) of drill holes based on the drill pattern and to highlight innovative workflow of transmitting the drill plan to smart drills for accurate drilling.

Feb 1, 2020

By Thomas M. Keevin, Gregory L. Hempen

A user-friendly model for environmental effects from underwater explosions is presently available. The model by Munday et al. (1986) is effective for determining fish mortality radii from underwater shooting. The IBLAST program (Coastline Environmental Services 1986) from this model includes estimates for both borehole-loaded explosives for demolition or rock removal purposes and midwater shots. Midwater shots may be used for fish population assessments or some seismic surveys. The program produces approximate mortality distances for planning purposes. IBLAST does have serious shortcomings of which users should be aware.

Jan 1, 1995

By Gungor Tuncer, Ali Kahriman, Umit Ozer, Abdul Karadogan, Mehmet Aksoy, Ertugrul Kaya, Deniz Adiguzel

This research was performed on the quarry that will be opened to produce aggregates and rock filling material at Catalagzi region at Zonguldak providence. Excavations will be done by drilling and blasting. However, there are some structures which can be adversely affected by blasting at the quarry. These structures are a methane exploration drill hole and a house at the distances of 340 m and 390 m, respectively. The one of the main goals of this study is to perform a preliminary assessment of possible damage effect of ground vibrations induced by blasting on these structures by risk analysis based on ground vibration measurements.

Jan 1, 2009

By Rakesh Raghavaraju, Bibhu Mohanty

The paper analyzes the decay of shock pressure as a function of distance from the borehole, and its implication on shock-induced fracture properties of the target rock as the first step in predicting fracture and fragmentation behaviour in a well-characterized rock.

Feb 1, 2020

By Diego Quezada, Carlos Munoz, Marco Arellano

It is well-know that the presence of fine materials in mining has a direct impact on the plant processes with a great influence in the total amount of ore production and recovery. In Cu mining heap leaching is affected negatively by the presence of fines material (< 100 # Ty) in leaching piles, where a decreasing in Cu recovery is achieved in a lot of cases. D&B practices used normally in mine operations can generate fines > 4% in blasted piles, but the principal effects are reflected in the downstream processes where pre-conditioning post-blast materials release greater quantities of fines.

Jan 1, 2010

By Sami Kara, Marsel Nabium

This paper provides an overview of the solution applied in underground Silver mine in Russia. The paper reviews the dilution problem throughout the entire mining process, and provides a rational approach to underground mine Blast design in order to minimize dilution

Feb 1, 2020

By Denis Rickman, Jon Windham, Stephen Akers, Byron Armstrong

The soil crater formed by detonation of an explosive charge is of considerable military interest because of the common use of explosives to create soil obstacles. The soil crater is also an important piece of forensic evidence for the investigation of terrorist bombings. With recent advances in numerical codes, modeling and simulation of explosively-formed soil craters is becoming an attractive means of analyzing this phenomenon. Consequently, the need exists to better understand the relationship between soil properties and the resultant soil crater. An extensive database has been developed for the case of explosives detonated in or above in-situ soils of various types. However, in most cases, the soil properties were either not adequately quantified or the soil materials themselves varied such that the gross properties were poorly understood. A research program is underway to improve methods of relating soil crater dimensions to soil identification properties such as USCS classification, particle-size distributions, and Atterberg limits, as well as to soil composition properties such as density, moisture content, and volumes of solids, water, and air. As part of this effort, both explosive detonations conducted over well-controlled and well-documented soil backfills and companion numerical simulations were studied. This paper presents an overview of the effort.

Jan 1, 2010

By Alejandro Ferrada Vergara, María Jesús Barros Godoy

Reducing costs while maintaining productivity and achieving good results is a constant challenge in mining operations, especially in the drilling and blasting stage, since a bad blast can affect production plans, increase costs, affect safety and jeopardizing the pit stability. Examples of undesirable blasting effects are: flyrocks, boulders, loading equipment damages, lower production rates, etc. In some of the biggest open pit mines using conventional blasting patterns visited by the authors, the pattern does not adjust properly to the rock mass, in most cases blasting polygons are large and the rock mass condition is variable within the designed blasting pattern. On the other hand, conventional blasting patterns with stemming columns use 40-50% of the blast hole with inert material (the stemming). Moreover, blasting engineers spend efforts to improve fragmentation results by increasing explosive charge in spite of having the negative effect of ground vibrations, with little or no success. The classic approach is "the more explosive in, the better the fragmentation is", furthermore it is assumed this relation is direct and infinite, but it is definitely wrong. This work challenges the notion of a limitless direct relationship between explosive charge and fragmentation, this means this is partially true but just up to a certain limit. In other words, there is still room to improve energy distribution among the classical blasting techniques without increasing the explosive energy by using air decks. In the work to be presented air decks are built using conical shaped stemming plugs called Paraplug®. The results obtained suggests a wedge effect acts in the bottom of the stemming column that cushions the shock wave and the air deck to reduce the detonation pressure (this is due to the decoupling factor resulted from the air deck). The demonstration shows improvements in fragmentation results, reduced vibration records accompanied with lower dust column and costs savings in explosive charge.

Jan 21, 2025

By Sami Kara, Marsel Nabium

As a mining project is developed from conceptual to production phases, there exists a variety of uncertainties and difficulties that affect the operation’s designs and economic values. A notable design parameter to be taken into account is the factor of dilution. Dilution is the waste material not separated from the ore in the stages of mining and is sent to the processing plant. It is defined at the ratio of tonnage waste mined and sent for processing over the combined ore and waste tonnage milled. Dilution reduction is one of the areas that offer metal mines an opportunity to increase revenue and reduce costs, resulting in enhanced profits. Effective dilution control programs require interaction on a multidisciplinary level. This paper outlines recent initiatives undertaken at Polysmetal Silver Magadam Mine to reduce dilution and increase revenue. This paper provides an overview of the solution applied in underground Silver mine in Russia. The paper reviews the dilution problem throughout the entire mining process, and provides a rational approach to underground mine Blast design in order to minimize dilution. The mining companies put a lot of effort into extracting lower grade while minimizing cost. The dilution control assists with achieving this goal. In Polymetal Silver Magadam Mine we succeeded to control more than 20 blasts by keeping almost the same grade measured in the face. The results indicated that using the adequate blasting timing design can help to separate the ore from the adjacent waste in drift blasting with different ore body configuration.

By Lazar Kricak, Zoran Teodorovis, Dragan Bogunovic

Scattering of delay interval around nominal value is an important issue in blasting practice. The scatter interval, as becomes wider, increases a probability of time delay overlapping adjacent blastholes. An excessive flyrock, ground vibrations, air blast and poor fragmentation are the symptoms for scattering related problems. Utilization of the short delays in the blastholes and longer delays on the surface are recommended solution to overcome mentioned problems. In contrast to global trends manifested through the application of electronic detonators and non-electric shock tube systems, revitalization of inexpensive electric detonators in combination with an accurate initiation system may be an acceptable solution. An extensive work was carried out at the Blasting Center Laboratory at the College of Mining and Geology, University of Belgrade, to develop a precise initiation system. As a result, Sequential Blasting Initiation System – Radio Frequency (SBIS-RF) was developed. It is expected that this system will increase blasting productivity, and reduce negative environmental impacts and total blasting costs.

Jan 1, 2008

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 Paul L. Matrin

This paper will discuss the recent and on-going drill and blast optimization measures at the Sparkhule Limestone Quarry, which have resulted in a 44% reduction of drill and blast unit costs per ton of broken limestone. This amounts to approximately $240,000 of drill and blast saving per year at current annual production rates of about 2.5 million tons (2.3 million tonnes) total material shot. The reduction of drill and blast costs were accomplished by a detailed and controlled in-the-mine drill/blast experimentation and cost evaluation using 8 different blast pattern designs and shots totaling approximately 267,000 tons (242,200 tonnes) of shot and mucked material. A careful review of the geology of the deposit was performed to determine the different rock classification/strengths/structural properties and to adjust blast designs to optimize fragmentation for the different rock types. Equipment loading productivity and crusher throughput performance were monitored as part of the evaluation process to assure that an optimal fragmentation of broken rock was achieved with the new blast designs. The study included the review of bulk explosive and accessory selection criteria (ammonia nitrate/fuel oil mix - ANFO, mini prills (high density ANFO), sensitized and un-sensitized emulsions at a 30% emulsion/70% ANFO blend), blast pattern design, charge diameter and the cost of drilling. Laser profiling technology was used to assure proper bench heights, stemming and sub-drill footage and front row burdens. High speed photography, video and still photos were taken of the different designed shots to assist in the evaluation of the performance of each blast. Powder density checks, size distribution, back break, detonation velocity and pressure measurements were taken. Different borehole diameters were used for the drill optimization study and drilling cost and productivities determined. A detailed cost comparison between in-house blasting and complete shot service was prepared to evaluate if shot service is a cost effective alternative to current in-house loading and blasting including a review of the new and pending United States Bureau of Alcohol, Tobacco and Fire Arms (ATF) regulations and associated owner costs/risks and potential benefit of shot service.

Jan 1, 2004

By Frank Sames

Blast vibration and airblast overpressure signals are generally rated and compared only by their maximum amplitude and the principal frequency associated with the peak pulse. The scaled distance concept is often used to predict peak amplitudes and can be applied for blasts in the same area of a mine to evaluate the statistical properties of a set of readings.

Jan 1, 1997

By G Dean Barrett, Ed Jr Smith, Calvin J. Konya

The purpose of the project was two fold: 1. To determine whether Pyrodex, a propellant, manufactured by the Hodgdon Powder Company, could be used as a substitute for high explosives for presplitting in granite and other materials. 2. To determine if Pyrodex, a slow reacting propellant which produces no stress waves in rock because it reacts subsonically, could cause the rock to crack similar to the results achieved with high explosives.

Jan 1, 1986

By J S. Brower

Disposing of the AMDP-1, Jackup drilling rig in the Arabian Gulf.

Jan 1, 1978

By John R. Schuring, Walter Konon

The 2.0 in./sec. peak particle velocity criterion traditionally used to protect structures from blast induced vibration damage is non-conservative for landmark structures. Various factors which must be considered in establishing vibration criteria for landmark structures are discussed. Existing criteria by past investigators for this class of structure are presented.

Jan 1, 1984

By G Alan Foster

The presence of approximately 600,000 attorneys in the U.S.A. and the determination by the courts that blasting is considered an 'ultra hazardous' activity makes every practical blaster aware that at some time during his working life he will probably be faced with defending himself in court.

Jan 1, 1982