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By Amund Bruland, Vegard Olsen

This paper presents analytical assessments around unintended misfire detonation, within rock debris drilling and bench top cleaning, primarily in the quarrying and mining industry. The main purpose of the work has been to see which operation has the lowest fatal accident probability. To be able to do this a risk analysis model is developed and the basics of the model are described first in the paper. Further a practical approach of the model use is presented. This includes a summary of general fatal injury statistical data, which is used to establish input parameters in the model. The result of the work shows that the rock debris drilling operation has at least half the probability of fatal injury compared to bench top cleaning. The result of the work should bring along rewriting of the Norwegian explosives regulation. The statistical data also shows that the blasting industry generally has a high fatal injury rate compared to other industries and basic risk reference levels. Risk reduction efforts concerning the examined operations are described.

Jan 1, 2008

By Xue Yongpeng, Zhu Zhenhai, Zhu Ming

The purpose of the Solid Medium Controlled Blasting Technique and Its Applications is to have the inside of the vessel-shaped framework (e.g: oil tank , water pool, gas chamber, chimney, water tower, grain warehouse and etc.) or the one side of the thin wall-shaped structure(e.g: steel bar concrete wall and etc.), both of which are intended to be demolished, inserted with the required solid medium (e.g: soil , sand , coal, salt and etc.) ,in which there is a certain mass density, and then through which the blasting energy is transferred to fulfill the blasting task. For such a technique, it is necessary to bury the explosives into the inserted solid medium and then to start the explosion to blast the intended target into pieces. The filling of the solid medium may be done mechanically or by man. Compared with the water pressure blasting technique, this one has the characteristics of good effect. wide application, simplified construction procedure , safe and reliable operation and small vibration (less vibration than water pressure blasting by 80% to 90%)in particular without any flying stones, thus resulting in better and comprehensive social and economickfficiency.

Jan 1, 2000

By Egonk Arriagada, Jair Alarcon

The efficient use of energy in the ore comminution process is an increasingly important strategic issue for improving the productivity and competitiveness in the mining industry as is in recent years the related focus on reducing energy intensity on the atmospheric pollution and greenhouse gas emissions from its use.

Jan 1, 2015

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 Benedict C. Di Duca

In the underground construction industry. when bidding work, not only is the contractor faced with determining if rock: is in existence within the parameters of his work. he must also estimate the quantity and the most efficient method of removal.

Jan 1, 1990

By Dan McCutchen, Oettmeier

Kelly bar drilling and blasting is unique to Florida, the' Bahamas and other marine limestone areas in the world where blast holes are required but will not remain open for the loading of explosives. This type of rock formation usually yields 1.5 tons of recoverable rock compared to 2.2 tons per cubic yard for competent limestone. The loss of .7 tons per cubic yard is due to voids and sand in the formation. These deposits all contain water to the top of the blast holes which are collared only a few ft. above the ground water level. The working pit is a water filled lake which is excavated from the bank by draglines. These drills have been used in Florida for many years to depths of 65 ft or less.

Jan 1, 1991

By Thomas L. Barkley

My historic auditing of Underground Drilling and Blasting Practices has demonstrated to the author the need for reviews of many mines' procedures in these processes. Poor understanding of the basic principles and practices of the drilling and blasting science in Underground Development Mining has created significant costs to mining operations in many instances.

Jan 1, 2019

By Sharkey Bowers

This study was undertaken in order to determine a conservative estimate of the attenuation rate of vibrations through the shallow limestone in South Florida due quarry blasting. The natural limestone bedrock in occurs at or near the surface in southeastern peninsular Florida. While the shallow overburden soils is advantageous for mining purposes, vibrations from blasting has been a contentious issue in South Florida due to the proximity of the mines to several residential communities. White Rock Quarries and Krome Quarries are two active mining facilities in South Florida which generate numerous complaints, insurance claims, and lawsuits from residents in nearby communities who claim that the vibrations cause damage to their houses. Both quarries are located on the eastern edge of the Everglades, with thousands of nearby residences at the western edge of development in Broward and Miami-Dade Counties. Data obtained from over 400 publicly available blast monitoring and associated seismograph reports from White Rock Quarries were reviewed and compiled. The data was used to emperically develop a conservative estimate of the ground attenuation rate based on the scaled distance from the blast origin, which can be compared to Figure B-1 from USBM RI 8507 to determine whether it is feasible if damage could have occurred at a given property.

By Donald Hurd, James Rowland, Richard Mainiero

In previous conferences the authors have reported on toxic fumes generated by the detonation of ANFO. The research reported here extends the earlier work to include an emulsion blasting agent and ANFO/emulsion blends. Explosive mixtures were shot in 4-inch Schedule 80 steel pipe (outer diameter 4.50 in (11.43 cm), inner diameter 3.83 in (9.72 cm)) in a chamber in the experimental mine at the Pittsburgh Research Laboratory (PRL). Following each shot, the fumes in the chamber were analyzed using on-line instrumentation.

Jan 1, 2001

By Mark S. Rayson, Jessy Lee, David O. Johnson, Matthew R. Rawls

The ability to manipulate the structure of liquid chemicals in an explosive is important in mining applications, where precision blasting is crucial for the safe, reliable, economical and eco-friendly extraction of ores. Static mixers allow explosives, emulsion-based in particular, to be custom-made as they offer precise and reproducible mixing without the need for moving mechanical parts. In this paper, we perform numerical simulations on the laminar mixing of two nitrate-based fluids in a Kenics static mixer unit for various mixer parameters. Two numerical methods were investigated in the study of the mixing pattern: solving the mass transfer equation and using particle tracking. The former introduces artificial numerical diffusion which can lead to spurious smearing of the component boundaries, a problem that can be avoided with the latter technique. We have also demonstrated that the particle tracing method is capable of qualitatively predicting the blending patterns under the conditions studied.

Jan 1, 2014

By Jorge Cárdenas, Diego Gamarra

In previous phases of the mine, a landslide resulted in several losses in production delays. The stability of slopes in a mining operation is critical for the sustainability of the operation, as they are exposed to vibrations and damage caused by blasting. Therefore, it is essential to implement controls and innovative technologies to reduce these vibrations levels. This study focuses on the application of low-energy emulsions with lower densities than conventional explosives, developed to reduce vibrations and the energy delivered to the rock mass adjacent to the near blast holes as a buffer row. Near field studies were carried out by embedding triaxial geophones. Vibrations were recorded, and mathematical models of vibration associated with different types of explosive mixtures were generated. This allowed us to determine the benefit of implementing low-density explosives in reducing vibrations compared to Heavy ANFO explosives. The application of low-energy explosives with densities ranging from 0.7 to 0.8 g/cm³ and Relative Bulk Strength (RBS) of 51-65 allows for a 40% reduction in vibrations compared to the detonation of Heavy ANFO explosives.

Jan 21, 2025

By Francisca Tapia, Jorge Blázquez, Paulo Couceiro, Patricio Vergara, Luis Manriquez, Luis Martínez, Juan Navarro

Efficient energy transmission is critical for effective rock fragmentation in open-pit blasting. However, in zones with highly fractured or soft rock, mismatches in acoustic impedance between the explosive and the rock can lead to significant energy loss. These mismatches reduce fragmentation efficiency and, when energy input is increased to compensate, can trigger unintended side effects such as NOx fume generation. This paper presents a novel methodology that integrates the Fragment Size Energy Fan model with acoustic impedance theory to dynamically optimize explosive energy delivery. A redefined impedance formulation captures volumetric energy transfer and enables the calculation of a Rock Impedance Factor (RIF), calibrated through non-linear regression. To operationalize the model, rock impedance is estimated using the X-4Traits Model—a meta-learning algorithm that interprets Measurement While Drilling (MWD) data from both autonomous and manually operated drills to produce high-resolution, spatially distributed impedance maps. The methodology was calibrated and applied at Minera Escondida Limitada (MEL), using data from over 218,447 blastholes and 526 blasts. Two case studies illustrate its application: Expansion 1 demonstrates improved fragmentation consistency and a 10.7% reduction in powder factor by aligning explosive energy with local impedance variations; Expansion 2 highlights the model’s utility in managing NOx emissions in fractured zones by optimizing energy distribution and confinement without compromising fragmentation. This impedance-based framework provides a robust tool for improving fragmentation outcomes, optimizing energy use, and enhancing control in geologically variable blasting environments.

Jan 26, 2026

By Ian Bell, Shahram Tafazoli, Bahram Sameti, Aylin Azmin, Edmond Chow, Nima Ziraknejad

Image-based rock fragmentation analysis methods have been applied by blast engineers to estimate rock size distribution for over 25 years. These methods utilize a wide range of image segmentation techniques, from manual to fully-automated, to delineate the edges of the rocks in the image. In most commercially available image-based rock fragmentation analysis systems, rock delineation results are converted to physical rock sizes by introducing one or more reference objects (e.g., basketballs or other objects with known geometry) to the scene as size-scaling references.

Jan 1, 2014

By David E. Siskind

Increased mineral consumption and environmental concern have caused much interest in potential damage and annoyance from ground vibration and airblast produced by production blasting in surface mines and quarries. Ground vibrations are traditionally blamed for "shaking the house to its foundations," but often the airblast is responsible, particularly when the distances from mine to structure are large. Simultaneous measurements of ground vibrations, structure vibrations, and indoor and outdoor noise from blasting are being used by the Bureau of Mines to determine the relative importance of the ground and airborne blast energy in shaking the structure and making windows, dishes, etc., rattle.

Jan 1, 1977

By Y Wada, Y Ogata, T Nishida

"Shaped charge is used for blast demolition of steel construction in general. It is important tocontrol movement of cutting part with shaped charge for the blast demolition of steel construction.Movement of cutting part was studied in the small scale experiment with steel bar. A numericalsimulation using the Discontinuous Deformation Analysis (DDA) was carried out. The DDAmethod was applied to the full scale blast demolition of steel construction. Results of thesenumerical simulation was compared with the blasting demolition work of steel tower."

Jan 1, 1999

By M. Gonçalves Peixoto da Silva, E. Rodrigo Carvalho Souza Siqueira

Mining in narrow veins is commonly applied for precious metals, generally carried out to extract gold in underground mines, due to the ore occurrence on narrow veins, mainly up to 2-meter large. The current work presents the implementation of the methodology in a zinc mine located in the state of Minas Gerais in Brazil. The Vazante Mine through the years has always carried out mining on stopes with a thickness larger than 3,5 meters, but nowadays due to the need to reduce the waste planned in its blocks, as well as increase the useful life of mine, mining has been implemented in blocks that are less than two meters. Given this, the challenge is to be able to carry out blasts that does not exceed the operational dilution required and does not generate an impact on recovery, as working with extremely heterogeneous stopes. This study seeks to correlate the main characteristics of stopes and its relationship with the results obtained in the execution of those blasts. Also, it proposes an analysis between the empirical data, and existing theoretical references, creating ideal mining parameters, such as minimum thickness, maximum height, and optimum timing in the blast plan. One of the main challenges for carrying out this mining method is the control of operational dilution, generally pointed out as the biggest difficulty for companies that adopt this methodology, due to the thickness of those stopes, any displacement can make it unfeasible, thus the technical level on carrying out the drilling and loading of these blocks must be impeccable, an understanding of the structural geology of the site is also essential for dilution control. The outcome will be a set of ideal parameters and mining methodology to guarantee the success in execution of these blocks, thus bringing a financial benefit to the company.

Jan 21, 2025

By Douglas Bartley

As the economy continues to slowly recover, our industry continues to finds ways to increase productivity while being forced to cut costs. The drilling and blasting process is the starting point of any aggregate or mining process. Many people refer to it as the “Primary Crusher” as it will always be more efficient to crush rock with explosives energy than it will be mechanical energy. It is the more efficient use of this energy that is addressed in this paper.

Jan 1, 2012

By Tom Goforth, Rongmao Zhou

The interest of seismologists in mining explosions has increased substantially with the construction of the International Monitoring System (IMS). The IMS supports the Comprehensive Nuclear Test-Ban Treaty by providing global data coverage from seismic, hydro acoustic, infrasonic, and radionuclide sensors that will detect a host of natural and man-made events at regional (<2000 km) distances. Ideally, the recorded data can be used to identify those events that have explosive characteristics and therefore might be clandestine nuclear tests. The regional observations assure the detection of mining explosions, and these must be properly identified to avoid false alarms of the monitoring system. Cooperation with the mining industry, including documentation of the firing programs, provides critical information necessary to characterize the seismograms.

Jan 1, 2006

By Matthew K. Coy, Paul N. Worsey

The work described in this paper comprised the master’s thesis work of the primary author and was conducted at the Missouri S&T experimental mine. The objective was to determine if rubber tractor treads could be used as an alternative material for blasting mats. These treads are made from steel cable and vulcanized rubber and are very tough. However, once they reach the end of their life on mobile equipment, they are destined for a landfill, or dump site, because they are too tough to recycle. A potential alternative use for them is as blasting mats. Several discarded treads were obtained from Kolb Grading in St. Louis.

Jan 1, 2015

By J Edmund Hay, Harry C. Verakisl, Richard J. Mainiero, John J. Mulhern

As the first stage in the rulemaking process, MSHA prepared requirements for the approval and use of permissible explosives and blasting items in underground coal mines. These draft requirements known as "preproposals" were announced in the Federal Register in mid-1984. The draft requirements on the use of explosives were written as a revision to Title 30, Code of Federal Regulations, Part 75, Subpart N. The draft requirements for approval of permissible explosives including sheathed explosives for unconfined applications, approval of water stemming bags, approval of detonators and approval of blasting machines were prepared as Parts 15, 16, 17 and 25 respectively.

Jan 1, 1985