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By Ashley Haslett

A European Directive on Identification & Traceability of explosives came into effect on the 4th of April 2008. This directive is intended to establish a harmonised system for the unique identification and traceability of all packaged explosives, detonators, reels of detonating cord and primers used in civil applications across the European Union. The directive must be adopted into the national legislation of each European Union member state by the 5th of April 2009 with compliance achieved throughout Europe by the 5th of April 2012. The requirements of the Directive apply to all explosives manufactured, used and imported into the European Union from 5th April 2012.

Jan 1, 2010

By Rakesh Raghavaraju, Bibhu Mohanty

Prediction of fracture and fragmentation characteristics of a rock mass subjected to dynamic loads, such as in blasting remains a major technical challenge. The present study is aimed at characterizing the shock transmission properties in controlled experiments in small scale in a well-characterized granitic rock, under varying borehole coupling conditions. Single blast-hole tests were conducted in a granitic rock sample of 145 mm (5.7 inches) diameter and height. The boreholes (in two diameters: 6.4 mm (1/4 inch) or 9.5 mm (3/8 inch)) were loaded with detonating cord of varying charge weight (5.3 g/m or 25 grains/ft to 31.8 g/m or 150 grains/ft of PETN). The effect of explosion gas penetration into the target rock was eliminated by inserting a thin-walled copper liner along the borehole wall. Embedded carbon composite resisters were employed at varying distances from the borehole to measure transmitted shock pressure for two coupling conditions (i.e. air and water) at distances of 1x to 9x the borehole diameter. 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.

By Robert Jacob Cefalo

In 2019, the Bingham Canyon Mine, owned by Rio Tinto Kennecott Utah Copper Company, mined through the active underground that dewaters the pit. The active underground required the limitation of vibrations to avoid catastrophic damage or damage that would require work to the shotcrete and additional roof support. The surface design of the current sector was mined next to and through portions of the active underground.

Feb 1, 2020

By Iván Aguirre Palacios, Jean Guiroux Toro, Eduardo Valdés Guerra

Currently, mining operations seek to be competitive in the market. To achieve this, one of the relevant factors is to maintain and improve the productivity of the extractive processes, mainly the loading from the point of opening of the mineral bodies. To do this, many techniques suggest reducing production costs, with the first opening of your free-face up raises. However, there are different ways to carry out these open-face raises up opening processes, where the balance of costs and construction time must be well planned to meet production plans. Operationally, there are different techniques for its construction, the most common being Blind-Hole up Raises and those with drilling with current production equipment that operates mining operations. This study shows a methodology and the results of the implementation of access stack drilling with production drilling rigs for a maximum height of 15 m with electronic detonators in production blasting. Within the methodology used, Qa/Qc processes were considered in cargoes with explosives, instrumentation for monitoring (vibrations), VOD registration, among others. As a result, of a total of 12 raises up blasts, construction time was reduced by 45% and the cost of drilling and blasting (P&V) was reduced by 50%, for up raises with a maximum height of 15 meters. Regarding the efficiency of the heights, this was 97% compared to the planned drilling design.

Jan 26, 2026

By Steve Kane

Lightning is a very real problem in the surface mining industry. Today, as adverse market conditions continue to influence the surface coal industry, it has become necessary that all functions of the surface mining process become as efficient as possible. High production with reduced manpower is the winning combination of staying competitive in the market place. We at AMAX Coal are committed to staying in the coal business, but we have always been committed to providing a safe work environment for our people and will continue to do so in the future. Approximately two years ago, our Midwest mines installed state of the art lightning detection and warning systems at our mines. This paper will cover its application at Delta Mine; the benefits and problems encountered, and the impact this system has had on Delta Mine.

Jan 1, 1992

By C. K. McKenzie

Presents outline of flyrock model and a field procedure to validate predictions of maximum projection distance. Field results are presented from 13 field tests with two different hole diameters.

Feb 1, 2020

By Guillermo Lazcano Ríos, Jorge Parvez Aguirre, Alejandro G. Díaz Berríos, Felipe Rodriguez Alveal

Codelco's Chuquicamata Underground Division (DCHS) faces issues due to collapses in its subsidence streets, which hinders the advancement of the subsidence front and leads to the loss of areas and reserves. To address these issues, DCHS and Orica have developed a new excavation methodology based on pre-loading explosives in high drawbell. This methodology involves creating a high drawbell extending from the floor of the production level to the ceiling of the subsidence level, divided into two phases: upper and lower. A resin stemming is used to separate these phases. The excavation strategy adjusts to variables such as reception volume, fluffing, and excavation geometry, involving vertical pre-loading of the explosive and the use of a separating element between the phases. The test aims to validate the new excavation methodology and the retaining element in the rock mass, evaluating aspects such as drawbell geometry, impact on the rock mass, damage to the retaining element, and fragmentation. Wireless electronic detonators are used in the upper phase to improve safety by eliminating the need for physical connections, while traditional electronic detonators are employed in the lower phase. Low-density bulk emulsion is applied to minimize the impact on the Crown pillar and extraction point, and higher-density explosives are used above the subsidence level to ensure good caving. Results showed that the blast achieved 86% conformity with the theoretical design. Resin stemming allowed for 100% effective detonation in the upper columns, and the fragmentation obtained was 5.44 inches, which was less than expected. No damage to the Crown pillar was observed, and the explosive quality met standards. This technique has proven to be effective and viable, suggesting the possibility of eliminating the subsidence level in future levels, resulting in savings, and providing greater stability to the rock mass.

Jan 21, 2025

By Shannon Studden, Angela King, Allan Koski

Cliffs Natural Resources is an international mining and natural resources company with over 160 years of history. A member of the S&P 500 Index, the company is a major global iron ore producer and a significant producer of metallurgical coal. Throughout its history, employees have been the foundation of the company’s success, which has long embraced a focus on continuous business improvement.

Jan 1, 2014

By D. Scott Scovira, Thomas Gustavsson

The potential of hydrogen peroxide explosives was introduced to Thomas Gustavsson and Robert Håkland by Dr Miguel Araos through his development of hydrogen peroxide gel compositions (HPG). In 2020, Thomas and Robert developed a concept project with Boliden Minerals and received Swedish government funding to evaluate HPG technology in a mine environment. The project showed HPG reacted violently with mine mineralization and concluded that HPGs did not offer a commercial solution due to safety concerns. Thomas and Robert engaged with Stefan Nilsson to develop hydrogen peroxide emulsion (HPE) compositions and the process techniques to manufacture them. In 2021, laboratory work produced a promising low carbon intensity, nitrate free, ammonia free, emulsion formulation based on industrial grade hydrogen peroxide and a fuel-emulsifier phase. Design and construction of an HPE pilot plant and underground charging unit commenced. The manufacture of hydrogen peroxide emulsion shares several similarities with the production of nitrate-based emulsions in that the plant is a facility to blend a strong oxidizer solution with a liquid fuel phase into a finished emulsion. A key differentiator between HPE and nitrate-based emulsion is that the manufacture of HPE is a cold production technology in that neither the oxidizer phase (HP) nor the fuel-emulsifier phase requires high temperature heating to prepare raw materials. A successful proof-of-concept HPE evaluation ran from April 2022 to October 2022 at Boliden’s Kankberg underground mine in Sweden. This evaluation demonstrated HPE technology's safety, performance, production, handling, and indicative environmental benefits.

Jan 21, 2025

By M. Ramulu, A. K. Chakraborty, P. B. Sahu, C. Bandopadhyay, P. B. Choudhury

Human response to blast induced vibration and air overpressure is an unsolved problem that accompanies excavation process in mining. Pre-assessment and understanding of annoyance due to production blasting is probably one of the most important aspects of a successful mining operation. Complaints arising due to unoptimised blasts lead to various critical situations that hamper production. Inspite, this important aspect has been covered by a limited number of researchers in the world and probably least in Indian context. Human response is a complex phenomenon and the sensitivity of individual also vary from person to person depending on various factors like age, sex, literacy, health and exposure to mining. With ever increasing demand of minerals, opencast mines are expected to approach habitats and thus mine management may witness increased response to blasting. Many developed countries have their own guidelines based on scientific analysis, addressing such environmental problems, where as there are a few studies available in India. This study introspects above phenomenon in tune with mining requirements by analysing direct human response. This paper is based on a case study regarding the human response to blast induced hazards in a Manganese mine situated in central India. Advanced techniques of Critical Path Method and Multiple Response Analyses have been used to unearth important inferences on the response of different crosssections of population residing about the mine to blast induced noise, ground vibration and air overpressure. Various inferences drawn may provide guidelines to the planners, environment or safety departments and blasting official for safe and environment friendly blast design.

Jan 1, 2004

By J. P. Proulx, Richard O’Meara, Ruilin Yang

A blast optimization project was carried out at an Open Pit Metal Mine using the Multiple Blasthole Fragmentation (MBF) Model and the Multiple Seed Waveform (MSW) blast vibration model. The aim of the project was to optimize rock fragmentation of the ore blasts to significantly increase metal recoveries while keeping the blast vibration levels at the highwall under control. The project also examined the blasts in the waste rock using the Fragmentation model to expand the blast pattern and select economical explosives for drill and blast cost savings while minimizing any adverse effect on the dig rates. Two sets of near field signature blasthole tests were conducted in both hard ore and relatively soft waste rock. The information from the near-field signature blasthole vibration was used as input to both the MBF and MSW models, as site specific geological information interacting with blasting. The implementation of the full blast design is also input to the MBF and MSW models. A production blast for each rock type was monitored for blast vibration and rock fragmentation. The full blast information and the blast results are used to calibrate and validate the models. The Fragmentation and Vibration model were established for the two rock types at the mine. At each site the Fragmentation modeling was conducted in parallel to the Vibration modeling to ensure blast vibrations were under control while the rock fragmentation was improved. The Fragmentation MBF and MSW are each an integral part of the blast optimization tool. Various scenarios using different explosives, hole delays and blast patterns were modeled for rock fragmentation and blast vibration. The recommendations from the modeling project were to be field trialed at the mine. The implementation of the recommendations was expected to help the mine significantly in terms of the mining economics, and high wall stability and safety.

By Lloyd Litwin

The ARTA 2008 Project (Alpha Ridge Test of Appurtenance) was a Canadian Government sponsored deep water seismic survey carried out on the high arctic permanent polar ice cap. This Geological Survey of Canada operation was the second seismic research project in the high Arctic and was monitored by the Danish Government. Utilizing 100% air support from Eureka and then helicopters from an ice based tent camp north of Ellesmere Island, the five week study was accomplished in the early spring just after the sun returned to the far north.

Jan 1, 2011

By John Petty, John Loviza

Single sentence describing content-- "The best ally an Explosives Engineer can have in a court of law is a regulations enforcer stating all codes and standards were met on a jobsite".

Jan 1, 1996

By N. Skopak, W. Birch, A. Douglas, C. Johnson

Determining the origins of air overpressure has been a long-debated topic within the explosives engineering community. Historically, it has been accepted that the initial face movement gave rise to air displacement, resulting in an air overpressure pulse. Later research proposed that the air overpressure pulse resulted from the shockwave rapidly propagating through and impacting the quarry face. Most recently, researchers have derived that air overpressure is associated with the gas phase from which a gaseous product from explosives rapidly pours out the quarry face under high pressure. Significant research has strongly indicated that the time at which the air overpressure pulse exits the face fails to coincide with either the arrival of the shockwave at the free face or the initial face movement. Research has consistently shown that the shockwave arrival at the face occurs before the air overpressure pulse leaves the face. Therefore, to best determine which blast mechanism contributed to the initial air overpressure pulse, testing was aimed at verifying the precise time at which the air overpressure exited the faces compared to when the face first moved. This research describes tests using scaled concrete blocks, which provided the ability to control the key parameters necessary for the research to be successfully concluded. Black powder was selected as the energetic material to eliminate the production of the detonation wave while still inducing other gas-producing effects. The components evaluated were air blast arrival times in front of the face, the initial movement of the blast face, the precise initiation time of the blast hole, timing of pressurization within the rock mass (between borehole and face, or adjacent borehole), and the speed of sound in the air. A detailed timeline was created which portrays the actions within the blast to promote an understanding of the sequencing of events. The results showed that the initial face movement occurred at 17.57 milliseconds (ms) while the calculated time at which the air overpressure exited the face occurred at 7.07 ms. The large disparity continues to reaffirm the premise that the origin fails to coincide with the air pressure pulse. Average pressurization through the block occurred at a rate of 341.23 feet per second (104.15 meters per second) which resulted in the gas release pulse being calculated to exit the face between 4.41 and 6.21 ms. This pulse correlates more accurately with the air overpressure origin timing which will be the focus of continued research. Knowing the precise origin of blast-induced air overpressure will assist in being able to better control it through appropriate blast design.

Jan 1, 2024

By Robert Hopler

That some time in the year 1872 there was organized an association composed of practically all of the manufacturers of gunpowder and other high explosives in the United States, the members of which said association were as follows: E. I. du Pont de Nemours & Co., The Hazard Powder Company, Laflin & Rand Powder Company, Oriental Powder Mills, American Powder Company, The Miami Powder Company, and Austin Powder Company of Cleveland, all of which or their successors are defendants herein; that the object and purpose of said association was the elimination of all competition between the members thereof in the shipment and sale of gunpowder and other high explosives among the various States and Territories of the United States; that the only manufacturers of gunpowder and other high explosives which did not join such association at the time of its organization were the California Powder Works, The Sycamore Manufacturing Company, and The Lake Superior Powder Company, but your petitioner alleges that each of said three last named companies

Jan 1, 2008

By J. Schoonover, A. Moore

In the explosives industry, individuals face a multitude of hazards while working in mines, quarries, and construction sites. Safety becomes an ever-present driver as companies attempt to control costs, promote quality service and products, and grow business all while ensuring employees return home safely every day. One of the most challenging hazards that threatens the goal of absolute safety is flyrock. Ensuring that a blast does not result in rock leaving the blast area, thereby creating a danger for personnel in the vicinity, can be complicated due to the multitude of factors. Shot design, geology, operational procedures/techniques, explosive products, security plans, communication methods, and drilling practices can all adversely affect the safety of individuals helping execute a blast through an increased risk of flyrock. Flyrock can also pose a major threat to the public and other non-blasting personnel in proximity. Like many other industries encountering various challenging hazards, the explosives industry has recently adopted innovative technologies to help mitigate the risk of complex hazards such as flyrock. Specific applications of Unmanned Aerial Vehicles (UAVs), commonly referred to as drones, employed in the explosives industry can help reduce the likelihood and severity of a flyrock incident. This paper explores a case study and theories of how the integration of drone technology within blast security plans, mine planning, blast design, design auditing, and blast area clearance procedures can help to decrease the risk of a flyrock event through the provision of data and information previously unavailable. Multiple opportunities exist during a blasting operation to gather data using drone technology. It is these data-gathering opportunities that can be leveraged to be maximally equipped for the mitigation of flyrock. Better data from drones can be sourced and used in security plans and clearance measures as well as utilized during mine planning and blast design. Increases in the quality and quantity of information during these crucial steps of blasting has proven to be an effective way to increase the peace of mind for explosive end users. This peace of mind, along with design flexibility and adherence to performance, is why the integration and utilization of drone technology is key for effective flyrock risk reduction

Jan 1, 2024

By Ambrose Buchanan, Rob Farnfield, Charles Adcock

Beginning on 7th September 1940 the City of London was subjected to 57 consecutive days of bombing in what became known as the ‘London Blitz’. To commemorate the 70th anniversary of this event a television series was commissioned that required the open detonation of World War 2 equivalent bombs close to purpose built structures constructed using period design and materials. The structures were built on a remote test facility in the North of England that is able to fire large quantities of explosive in the air.

Jan 1, 2011

By G Alan Foster

Many complaints generated from blasting operations result from the marked human response to ground transmitted vibrations and air blast effects and so many authorities have considered the regulation of blasting in terms of human response rather than, as previously, in terms of preventing damage to structures.

Jan 1, 1981

By Brian Micke, Mick Gavrilovic

The problem of rock hang-ups in underground mining operations has been a continuing one since the days of the “hang-up man”. This position commanded the highest pay of any underground worker in many historical Western U.S. underground bulk-mining operations, due to the occupational hazards of the job. Although underground mining techniques and especially work practices have changed greatly since then, the hang-up problem is a continuing one in many mines which use gravity flow of coarse rock in their transport systems or in those mines where stressed ground causes rock slabs to spa11 and bridge rock passes and stopes. In addition, with mechanized underground open-stoping mining methods now being used in many different types of ore deposits worldwide, this problem has again emerged as a very significant one in many of these highly mechanized operations. This is especially so where the remote operation of loaders is used for removing blasted rock from underground open stopes.

Jan 1, 1999

By Raden Haris Handayana, Jihan Farhan Lubis, Milia Putri, Tengku Deli Hamonangan Hasibuan, Sani Salahudin

An environmental issue that must be controlled from coal overburden blasting near the structure is ground vibration. Damaging ground vibration is the effect exerted from residual energy from blasting that does not work to fracture the rocks. Sebuku Tanjung Coal is a coal mining that operates T3 Pit adjacent to the High Voltage Tower. This structure is included in the Class 5 building with a maximum Peak Particle Velocity (PPV) of 40 mm/s. The shortest distance from the blasting location to the structure is 105 m. The initiation system used is electronic detonators combinate with emulsion as an explosives type. In Indonesia, the government regulated vibration limitation on SNI 7571:2010. The blast outcomes targeted are PPV below 40 mm/s, fragmentation size <80 cm for Excavator Komatsu PC-2000, and digging time <12 seconds. In this paper, the blast design was engineered by conducting Signature Hole Analysis for optimizing delay timing configuration and Scale Distance regression analysis to determine optimum charge weight per delay at the blast site. PPV results from 30 blastings achieved 100% below 40 mm/s with the range of about 1.773-30.250 mm/s. The deviation between PPV prediction to PPV actual is less than ±18% which provides the blasting with electronic detonator resulting in good PPV prediction for controlling vibration. The average fragmentation size (D80) is 55.81 cm in the 1st layer and 54.81 cm in the 2nd layer. The average digging time is 10.30 seconds in the 1st layer and 10.12 seconds in the 2nd layer.

Feb 6, 2023