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By Travis A. Davidson, Ralph E. Burnham, Cathy Aimone-Martin, J. Kelly Ratliff

Blasters face a long list of tasks to execute daily—from vehicle inspections to blast design and layout, hole loading and tie-in, securing the site, and finally, safely executing the blast. Good practices and, in most cases, regulations and requirements necessitate documenting their work, specifically their blast report. While some blasters use paper forms, others use electronic means to streamline the process. The authors have served as attorneys and expert witnesses in representing companies and individual blasters in numerous administrative and legal matters in which documentation of the blaster’s work was both critical and detrimental to the effectiveness of defending their work. This paper discusses in a case-study manner the authors' observations concerning good blast report format, specific observations around electronic and paper report completion, record-keeping, seismograph setup and recordkeeping, video and photo documentation, internal auditing, and other topics related to documenting the blast. The paper aims to serve as a discussion guide for blasters to improve their blast record-keeping process, develop better practices that effectively document their work, and allow them to defend their work should a claim arise concerning their operations.

Jan 21, 2025

By Brian T. Burch, Paul N. Worsey

When fired, submerged Linear Shaped Charges (LSCs) lose all effectiveness in the cutting of steel. Users in underwater applications have reported having to substantially increase the charge size to the point where brute explosive force shears rather than cuts the target.

Jan 1, 2015

By Jack Eloranta

The winning of metals often requires fine grinding of very hard ore. The US Bureau of mines measured compressive strengths exceeding 100,000 PSI (700 MPa) in Minnesota taconites. Grinding down to 300 mesh (50 µ) is required for some fine-grained taconites. While other metal ores may not be as strong, significant grinding costs are the rule rather than the exception. One author recently reported that a 7% drop in grinding costs would fully offset a doubling of the drill and blast budget. Another author found that drill and blast costs were 13% of the costs of producing iron ore concentrate while fine crushing and grinding were over 60% of the cost of producing concentrate.

Jan 1, 2013

By Chris Uys, Johan Labuschagne

Sishen Iron Ore Mine, located in the Northern Cape, is an open cast mine excavating approximately 100 million tons rock to produce 25 million tons of high grade haematite ore per annum. The size of the pit is approximately 12 km ‘1.5 km ‘150 metres. The final depth is planned to be around 350 metres. It is hard rock mining operation employing the conventional truck and shovel method. Mining benches are twelve and a half metres in height and are divided into blasting blocks, each consisting of approximately 300 000 tons of material.

Jan 1, 1997

By Lon Santis, Dale Ramsey

The use of aircraft to support blasting operations in mines, quarries and construction sites goes back to the early days of aviation. Invaluable at times, aircraft use has been limited by cost, the unpredictability of weather impacts and other factors. Recently several technologies have matured to open up a new way to acquire aerial data with unmanned aircraft systems (UAS), commonly called drones. Equally important, the U.S. Federal Aviation Administration has recently implemented an exemption process and rulemaking to implement the commercial use of UAS into the United States’ National Airspace. The skies are opening for many applications of UAS. The most notable may be photogrammetry, which is the science of making measurements from photographs, especially for determining the exact positions of surface points.

Jan 1, 2016

By Türker Hüdaverdi, Özge Akyildiz

"In this research, image analysis technique, Kuz-Ram and KCO Models were used to examineefficiency of the quarry blasts. Investigations were performed in Cendere region, Istanbul. As a firststep, image analysis software was used to determine particle size distribution of muckpiles.Additionally, the results of KuzRam and KCO fragmentation models were compared to the results ofthe image analysis technique. The efficiency of KuzRam and KCO models was investigated and theimportant points to be considered were explained. Additionally, the effect of the rock factor valueson the size distribution curves was investigated. The blasthole diameter is 89 mm. (3.5 in) in thestudied quarry. Each measured blast has a different burden, spacing and stemming length. Blastholes was drilled in a staggered pattern. It is concluded that, KuzRam and KCO models can be successfully used to determine fragment size distribution in Cendere Region Quarries, Istanbul. Site engineers can predict blast fragmentation using the theoretical fragmentation models and they may change blast design parameters before blasting operation if necessary. It is possible to calibrate the Kuz-Ram and KCO fragmentation models using the measurements obtained by image analysis technique."

Jan 1, 2016

By Joseph Nawrocki, Margaret Hettinger, Dr. Catherine Johnson

"Optimized rock fragmentation is essential for minimizing downstream costs to mining operations.Photographic fragmentation analysis, vibration monitoring, and high-speed video all providemeasurements of blast effectiveness and supply data that allows operations to modify blasts to achieve downstream goals."

Jan 1, 2016

By Tom Snyder, John Brulia

Part 4 is the final article by the authors on hazardous materials (HM)transportation safety and compliance for U.S. shippers and carriers who offer and transport commercial explosives in commerce on public highways. This article covers hazardous materials (HM) cargo segregation and securement of non-bulk packaged explosives.

Jan 1, 2015

By Ruilin Yang

"Blast vibrations are essentially a strain/stress wave propagating in rock or structures inthe vicinity of a blast. However, blast vibration has always been quantified in terms ofpeak particle velocity (PPV) or acceleration (PPA), and a meaningful relationshipbetween blast vibration and strain/stress has not been established. The determination ofthe dynamic strain from blast vibration may improve quantification of blast damage andselection of a blast vibration limit for critical structures or high walls. Dynamic strainrelates to rock mechanics or material strength more directly than peak particle velocity(PPV). This paper documents a method to calculate the three-dimensional dynamic straintensor from recorded blast vibration signals. The method is based on determination of thedisplacement gradient at a point of interest for each time instance during the vibrationduration. The method to calculate dynamic strain is applicable to generic seismicwaveforms including near and far field blast vibration from a production blast withmultiple blast holes. In order to minimize measurement errors the specifications of thespacing between monitors and the sampling frequency of the vibration recording aredescribed."

Jan 1, 2012

By Tom Short

"Construction blasting covers a very extensive variety of explosive applications. I will discussseveral of these with you and then show slides from my collection, starting in 1956, which will betterillustrate the types of blasting under discussion."

Jan 1, 1991

By Ron Frye, Carl Liibbe, Wayne Curtis, Julie Pecori, Dan Leach

Test work comparing the performance of a Low Density Porous Ammonium Nitrate Prill to regular Porous Ammonium Nitrate conducted in Pennsylvania and New York showed that less ammonium nitrate was required to perform the same work and that improved sensitization of an emulsion/ammonium nitrate blend reduced “orange fumes”. Fragmentation was similar in all tests with improved heave and throw experienced.

Jan 1, 1997

By Michael Olmsted

Inspection of boreholes prior to blasting can result in cost reductions as well as increases in efficiency and safety. Until recently, borehole inspection was performed in two manners. For simple inspections, a flashlight was used to view the upper part of the hole. More thorough inspections were performed with long tool strings developed for oil field applications. Borehole inspection tools developed specifically for mining and blasting applications have now been developed. Video Cameras developed for borehole inspection have been in service for several years. Now measurement tools are available, developed specifically for mining.

Jan 1, 2000

By Alexandre Passos, Giorgio De Tomi, Tatiane Marin, Dennis Cremonese, Jacopo Seccatore

"In the mining industry, rock excavation is the first phase of the comminution process. Downstreamoperations such as secondary breaking, crushing and milling terminate the process, reducing the size of the grains down to the desired particle distribution. In such a cascade process, every process upstream heavily influences all the downstream operations. When rock excavation is carried out by drilling and blasting, a very economic source of energy (the explosive) is used at the utmost upstream; a more expensive source of energy (electricity) is employed for all the downstream phases. This means that managing the correct employ of the explosive energy is a form of managing the whole process, controlling the operational costs and therefore the profitability of the whole business. We simulated this cascade behavior, using as a starting point the experimental data obtained from small-scale block blasting, evaluating the influence of blasting on the grindability of the blasted material. This study showed the reduction in visible (particle size) and invisible fracturing (micro-cracking, resulting in a reduction of the Work Index WI). The particle size distribution for full-scale blasts was estimated by means of algorithm simulation, then we simulated the behavior of the comminution plant fed with the material possessing the characteristics previously estimated. All the costs (drilling, blasting, electric energy for the engines of the crushers and mill) were calculated and charted. The results show a clear curve that allows to estimate the minimum operating expenditure (OPEX) for the whole mine+plant framework. Being the WI dependent on the output on the blast, one can manage the performance and the expenditure of the whole comminution process by adjusting drilling and blasting parameters For any given mine, it is possible to perform a simulation and encounter the minimum OPEX scenario for the comminution process and managerial choices can be oriented accordingly. In a cascade productive chain as mining is, responsible strategic choices must be taken looking at the entire production framework. Compartmentalized managerial staff and budgets for separated production areas are not acceptable anymore. Somehow higher costs upstream can lead to effective decrease in costs and increase in efficiency and productivity of the processes downstream."

Jan 1, 2016

By Noelia Valencia, Carlos Agreda, Jean Arenales, Juan Llerena

"In this technical paper is reported the several tests and the preliminary results that has been obtained so far. It must be emphasized that this investigation was started several months ago.On the other hand, it is known that acid water exists in some underground mining operations as well as in open pit mining operations all over the world. Taking into account this problem, our work teamdecided to carry out the present investigation. Therefore, it ensures a decrease in blasting costs avoiding this problem and as well as this, it allows to reducing fatal accidents that could occur caused by poor control of acid waters within mining operations."

Jan 1, 2016

By H G. Bosmare, G Bedser, C V. B Cunningham

Peak Quany has achieved substantial improvements to its bottom lie by giving close attention to blasting practice, and in pr@icnlar by introducing electronic delay detonators for routine production blasting. The precision and flexibility provided by these units has enabled the quarry to gain control over fmes and curtail oversize without increasing explosive usage. In addition, the extent of nuisance from blasting vibrations has been reduced.

Jan 1, 1998

The objective of current efforts by AQUILA Mining Systems Ltd. is the continued development of computer-based systems and techniques to automatically process and interpret monitored performance data from surface blasthole drills and mining shovels, and the management and coordination of these pieces of equipment by GPS (Global Positioning Systems).

Jan 1, 1995

By Charles Deacon

The mining industry is constantly taking greater cognisance of their operating costs as a strategy to counter the effects of falling commodity prices. As a result, optimal operating efficiency is more important than ever. One such operation is that of blasting. Considering the relative increasing costs of explosives and accessories it is desirable to optimise the number of blast-holes fired by maximising their individual output. This achievement may now only be possible following the advent of higher technologies in the form of modified explosives and electronic detonators. This paper reviews and introduces some techniques of blast monitoring, types of operations where each is most suited, resulting modifications to blast designs, and identifies some pitfalls to watch out for when analysing the results.

Jan 1, 2000

By Z X. Zhang

Ground vibrations from the blasts of the LKAB mine at the Malmberget town had reached 18-19 mm/s from year 2000 to 2002. From 2004 to 2010 the maximum vibrations had been reduced to 9 mm/s and most vibrations lowered to about 5 mm/s, indicating that the technical measures used in the mine are effective in vibration control. The major measure that has always been used in Malmberget mine is the method called Changing Initiation Sequence (CIS in short). Another method named Dividing Ring Blasting (DRB in short) is often applied to some special blast rings in the mine. Both methods have been proved to be successful in vibration reduction, and they do not need any additional costs. Because of the two methods, both maximum vibrations and average ones have been reduced by around 50% since 2004.

Jan 1, 2012

By David Ziegler, John Babcock, Gregory Poole

On December 9, 2003 at 3:59 PM EST an earthquake with a 4.5 magnitude occurred in central Virginia. According to a survey on the US Geological Survey website, this quake was felt as far away as Bridgeton Missouri, approximately 683 mile from the epicenter1. We recorded the vibrations from this earthquake on 14 seismographs that were set up for monitoring vibrations from blasting activities in the area. Having this data gave us an opportunity to compare earthquake and blasting vibrations. The amplitudes, frequencies and duration were much different than vibrations from mining and construction blasting. A common question we get from homeowners when discussing vibrations from blasting activities is “How does that compare to the Richter scale?” The goal of this report is to provide some simple answers for that question. The Richter and Mercalli scale are compared to the particle velocities in order to show their relationship.

Jan 1, 2005

By Paul Sainato

Recruiting and retaining students in the explosives industry is becoming increasingly important each year. With no undergraduate degree in explosives engineering currently available in the United States, it is from other industries and degree disciplines we must recruit. The 2014 annual ISEE conference saw the first anonymous online survey distributed to members of SEE student chapters of the International Society of Explosives Engineers. The survey contained questions about future job and career plans, ideal job placement, expectations of salary and current academic degrees. The purpose of the survey was to determine what these students expect or require from a career in the explosives industry, and their current path to pursue this. This information can help steer recruitment activities and job offers for graduating students. The success for both student response rates and interest from the industry has allowed space for a yearly update of this survey. A second survey was distributed in 2015 and included international students. This paper provides the data from a third online survey distributed to all student members of the International Society of Explosives Engineers, globally. Understanding the main incentives for a student to accept a graduate position as an explosives engineer can help us, as an industry; position ourselves to remain competitive in recruiting against other major degree disciplines.

Jan 1, 2016