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By Lon Santis, Michael Swisdak, John Tatom

The Institute of Makers of Explosives (IME) and A-P-T Research, Inc. (APT) have developed a quantitative risk assessment tool called IMESAFR (IME Safety Analysis for Risk) for managing risk from various activities undertaken in the commercial explosives industry. The first version was completed in 2006 and Version 2.0 of the software was completed in 2012, incorporating several major new features. The platform is now based on a Geographic Information System (GIS), providing a bird’s-eye-view to help visualize facility layouts and risk. Spatial data on potential explosion sites and exposed sites can now be automatically transferred from the images to ease users’ data input. Use of GIS data provides the ability to check facility compliance with quantity-distance (QD) standards such as the American Table of Distances (used by the Bureau of Alcohol, Tobacco, Firearms and Explosives, ATF), the NATO standard (used by Natural Resources Canada and other nations), or a user-defined table. Research conducted and knowledge gained over the last 10 years enabled changes in the algorithms and models that provide greater fidelity and reduce conservatism. Expert users can change global settings to more accurately match actual site conditions and the program runs using either Imperial (English) or SI (metric) units of measure. These changes and other new features are discussed and demonstrated.

Jan 1, 2013

By Christopher Jon Preston, Troy Williams, Daniel Roy

There has been significant progress made with narrow vein gold mines in which a second option for crushing has begun to attract attention. To ensure the profitability of a mine that has based its economics on the absence of a crusher station, more than just best blasting practices are required. Using a blasting operation itself as a primary crusher would undoubtedly save enormous capital costs as well as eliminate some of the costs of crushing ore with the result that considerable savings might be realized. The challenge would be to define the conditions necessary to make this type of operation feasible by providing consistent blasting methods that result in a significant paradigm shift with respect to both blasting and current underground crushing methods. A break model has been developed and applied as a technique in designing blasting patterns based on a unit charge blasting geometry and stress reflection from free faces. There are four components to this model and these are 1) unit charge, 2) thermodynamic/energy, 3) stress reflection, and 4) radial break. Some important changes in timing between holes and rows based on rock properties and the percentage of burden moved were also used. On-site testing at a narrow vein gold mine in Quebec Canada, provided measured parameters for the model. No underground crusher was planned - relying only on the fragmentation profile generated by ring blasting. The specification for muck was that the fragmentation profile needed to be 100% < 400 mm (16 in) with no overbreak - with dilution less

Jan 1, 2019

By Abraham Lindo

"Blasting plays a key role in hard rock underground mining. It is by nature a violent and destructiveextraction method designed to economically fragment the rock into a suitable size for it to be loaded and hauled as part of the specific mining process while controlling the amount of damage to the surrounding rock mass."

Jan 1, 2016

The following situation was submitted as an ethics case study for inclusion in the Journal. To the best of our knowledge, they are based on actual circumstances encountered in the field. Blowing the Whistle Protecting Confidentiality or Doing the Right Thing? This case centers around a construction job and involves a contractor, subcontractor/blaster, and a farmer/homeowner who lives near the job site. It is essentially a study of professional ethics versus morality, our professional code of conduct versus what is right or wrong.

Jan 1, 2007

By Amos Bryant, Jesse Davis

This paper compares the predictions of the latest Institute of Makers of Explosives Safety Analysis for Risk (IMESAFR) model versus physical test data recovered from ISO-1 and ISO-2 tests in Woomera, SA. ISO-1 testing included placing 1054 kg (2324 lbs) of ANFO (ammonium nitrate-fuel oil) inside an ISO container on a flat bed truck. ISO-2 testing was identical except the NEW was 4000 kg (8818 lbs). The IMESAFR predictions are based on model runs using the best match available to the actual donor type involved in the test. This type of debris analysis is not the standard output of IMESAFR, as the program is designed to assess the probability of human fatality. However, all of the IMESAFR predictions presented were obtained from the use of the actual model equations and algorithms without adjustment. Test results from ISO-1 and ISO-2 will be presented as well as findings from the comparison between model results and actual explosive results from the ISO testing efforts.

Jan 1, 2010

By Kain Petterson, P D. Katsabanis

Blast fragmentation, determined using image analysis was correlated to drill monitoring parameters in an open pit operation. Average fragment size and 80% passing size showed strong correlation with specific energy of drilling as well as with torque, while the same passing sizes did not correlate well with the rate of penetration. It was also determined that the uniformity of fragmentation decreases with the specific energy of drilling. Thus drilling monitoring parameters appear to be valuable in determining the blastability of the rock mass, enabling adjustment of blast loading to respond to changing conditions in the rock mass.

Jan 1, 2013

By David G. Borg, John Bussey

The new AIRDEK (tm) technique for pre-splitting in surface coal mines produces highwall conditions that have greater safety with lower costs for explosives, labor, and drilling. Successful applications have been made in highwalls ranging from 20 to 100 feet or more and in blasthole diameters from 3-1/2 inches to 12 inches.

Jan 1, 1988

This paper will review some of the work conducted in the past at the Dynamic Effects Laboratory to examine the use of stress waves and fracture mechanics in understanding dynamic fracture and fragmentation in blasting applications. Along the way, we will use photoelasticity and high speed photography to better understand the mechanisms of fracture and fragmentation.

Jan 1, 2015

By Tom Snyder, John Brulia

Part I is the first of a series of articles by the authors on hazardous materials (HM) transportation safety and compliance for shippers and carriers who offer and transport commercial explosives in commerce on public highways in the U.S.

Jan 1, 2014

By Curtis G. Kremer

"New explosives initiation systems continue to be developed as new technologies make advancements possible. Due to recent initiator developments, explosives users now have the most reliable, accurate, safest and easy to use systems ever offered. Three initiation systems recentlyintroduced which offer significant improvement over standard electric and nonelectric initiation systems include Magnadet, EXEL high-strength shock tube, and Redundant two-Dath surface delay systems. These three systems will be discussed zn cecail with rmpiasis on their functioning, safety characteristics, ani specific application areas."

Jan 1, 1991

By C. E. Johnson, R. L. Bauer, E. M. Johnson

In industry, the strength of a blasting cap is often equated to the type of explosive it can detonate. Comparable cap strength is becoming less important as nearly all caps manufactured today can initiate high explosives, such as primasheet, with ease. Previous studies were conducted to assess the quantity of energy released by various detonators into the directional propulsion of the detonator’s casing. However, the question of how much of this propulsion energy is needed to initiate an explosive remains unanswered. This study will assess the fragmentation size and velocity needed to initiate a high explosive when they are not in direct contact. For this study, primasheet was used as the main charge as it is relatively insensitive and can be situated in different positions relative to the detonator. Electric, non-electric and electronic detonators were used to evaluate initiation potential. The primasheet is observed in response to being in contact with a detonator, and not in contact with the detonator at various distances and angles. This allowed the quantity of energy transferred into the primasheet to be observed and for the initiation of the sheet to be recorded using high-speed video. This study will report the energy necessary to initiate the primasheet at various distances and angles from the charge from a number of widely used, commercial, hot wire blasting caps.

Feb 6, 2023

By A. Lindo, M. Held

The formation of NOx fumes is an undesired occurrence and is dependent on a variety of variables. Methods for detection of such fumes with blast analysis tools are available using color schemes for grading, but no quantification tools to measure concentration and cloud totals exist today. In cooperation with DIRS (Digital Imaging and Remote Sensing Laboratory) at RIT in Rochester, NY, Austin Powder has been looking for methods and techniques to identify and quantify total amounts of NOx by capturing cloud activity via a video feed from a drone in combination with measuring NOx and subsequent cloud modeling (i.e., plume segmentation). To accurately measure fume events, Austin Powder and the RIT team have been collaborating in performing small scale blasts at an Austin test facility and then transferring knowledge learned to full scale blasts at customer sites. The collected data will allow to identify any relationships between the total amount of explosives used and the quantity of NOx produced. The analysis of the total amounts of NOx and identification of blast areas those fumes originate from will help to better understand key factors that contribute to their occurrence as well as to quantify the severity of such events. By quantifying the magnitude and concentration of fumes generated by non-ideal detonations, the blasting technique can be optimized to minimize unwanted environmental effects and improve public perception of blasting as a necessary component of societal progress

Jan 1, 2024

By Maja Franjic, Ian Tolliday, Chris Collins, James Wiltshire

Ammonium Nitrate Emulsions (ANE) are a large segment of the explosives market for the mining industry. These emulsions are generally designed to be very stable but when breakdown does occur, removal of the resulting thick, crystallized material can be difficult, hazardous, time consuming and costly. A heavily crystallized emulsion cannot be pumped, so manual removal often becomes necessary. Buildup of semi-solid layers of crystallized emulsion can occur in bulk storage tanks or in truck compartments. In these situations, a manual cleanup involving hazardous confined-space entry and a significant amount of downtime is usually required. Once the crystallized emulsion is removed from the equipment, there is very expensive disposal of the resultant waste via a licensed trade-waste company. A much more desirable solution for dealing with waste emulsion is to completely break the emulsion, allowing the oxidizer and fuel phases to separate into two distinct layers. These layers would then be readily pumpable and could be disposed of much more economically. It may even be possible that the separated oxidizer phase could be repurposed as fertilizer and the fuel phase could be used to manufacture granular ANFO explosives. There are some existing products on the market for breaking emulsion explosives, but these generally need a high degree of mixing into the emulsion to achieve adequate breakdown. The aim of this study was to identify surfactants systems (demulsifiers) capable of effectively breaking a range of waste emulsions with minimized agitation. This paper describes the development and performance testing of novel demulsifier products. The test work involved a comprehensive series of laboratory screening tests, where the demulsifier formulations were optimized. A highly efficient formulation was identified, and field trials were conducted on real world, full-scale waste emulsions. Results will be presented that demonstrate a viable solution for the disposal, and potential re-use, of waste ANE in the explosives industry.

Jan 21, 2025

By Lon Santis

This paper analyzes 110 serious accidents that occurred during the use of commercial explosives in mining, construction, and other industries since 1992. Data from the Mine Safety and Health Administration (MSHA), the Institute of Makers of Explosives (IME) members’ reports, and media reports were used. Only accidents that resulted in a fatality, significant lost work time, or injury to the public were considered in this analysis. The accident data were analyzed for trends in frequency, type of industry, cause, type of individual harmed, and geographical region. Although the data showed that explosives accidents are decreasing in frequency, still, 29 people were killed and 134 injured. Eightyfive of the accidents occurred in mining, 17 occurred in construction, and 8 occurred in other industries including oil recovery, seismic exploration, agriculture, logging, boiler cleaning, and avalanche blasting. As other studies have shown, flyrock and failure of blast area security caused over half of the accidents. Mishandling, misfires, or fumes caused just over one-third of the accidents. Lightning and drilling into explosives were responsible for the remainder of accidents.

Jan 1, 2003

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

By Randall Head

The drilling at the Taum Sauk Reservoir was a unique compilation of the latest technology and everyday common sense. This site is comprised of rhyolite, which is 30 times harder than limestone in comparison. Using some of the most state of the art drills, coupled with GPS guidance, angular drilling systems, and an ordinary piece of string, some of the most amazing drilling feats were accomplished. By constructing the new dam on top of a mountain that had been blasted once before nearly 50 years ago treacherous conditions for the drills and crew were a challenge. The drills had to be flown in by cranes to get to their locations, where they then drilled anywhere from 2.5 to 6 inch (6.4 to 15.2 cm) holes at angles up to 24.4 degrees. Custom drill bits were designed by the drilling crew to tackle feats such as drilling holes up to 120 feet (36.6 m) deep. A main challenge was the shape of the reservoir, as it is not in a straight line, but rather round, so no technological way was readily available to use to drill. Common sense came in and an ordinary piece of string was used to aide in drilling the hole. A revolutionary step was that our drill was used to core our own samples. By using our own equipment, we were able to complete this task for one-third of the cost of having a third party contractor obtain the core samples. On this unmatched jobsite, it has been established that technology has come a long way, but when all else fails, a piece of string will do just fine.

Jan 1, 2010

Investigating blast vibrations typically utilises scaling and attenuation models for prediction of vibration amplitude over a range of charge weights and distances. A number of generalised relationships have been established from many years of far-field data analysis, where small changes in charge weight and ray-path distance are less critical. Under far-field conditions, small variations in local geology or geometry do not significantly affect the vibration scaling behaviour over an expected range of data. In the near to intermediate-field (less than 5 times the explosive charge length), small variations in wavepath and rock mass conditions between a blast and a monitoring point can greatly affect the outcome of vibration modelling. This case is especially true for underground blasting in sublevel open stoping, where the paths of blast-induced vibrations regularly encounter voids and preconditioned ground.

Jan 1, 2010

By Yogesh Narula

Nevis Bluff Landslide - On September 17” 2000, a rockfall measuring lO,OOOm3 at Nevis Bluff, New Zealand, triggered a loday emergency. It ended when a hazardous column of rock that towered over State Highway 6 was finally shattered. The operation called for unusual and unique solutions using aerial bombing and inverted blasting techniques, not known to have been attempted before under these conditions, anywhere in the world.

Jan 1, 2002

By Carl Hendricks, Malcolm Scoble

There currently exists no viable means of obtaining continuous feedback on blast efficiency. This paper describes the adaptation of a loading shovel to serve as a diagnostic tool to evaluate the success of ground preparation. Work undertaken in a large western Canadian open pit involved microprocessor-based instrumentation for the performance monitoring of an electric mining shovel. The monitored shovel responses proved to be reliable indicators of variations in muckpile diggability. This approach is considered to provide a very comprehensive survey of post blast conditions since such a shovel interacts which every cubic yard of a blast.

Jan 1, 1990

By Donald Wagstaff, D. Scott Scovire

The Coeur Rochester Mine is the largest primary silver surface mine in North America. Throughout its 17-year life, gold and silver grades leaving the tertiary crusher have typically been, on average, slightly below the mined bench grades as determined by blast hole assays. On a project-to-date basis, this grade variance is well within industry standards. While these variances are acceptable, mine personnel continue to study ways to further minimize the grade differences. One suspected cause for lower than expected head grades are ore loss and dilution resulting from blast-induced shot movement. In regard to grade control, the underlying design principle for non-electric blasts is the generation of uniform movement of the blasted rock material. Using one or two uniform directions of initiation, ore control methods at Rochester currently include adjusting flag lines on the muckpile in an attempt to account for displacement from original, pre-blast locations. To improve upon standard non-electric blasting practices, a series of evaluation blasts using an electronic initiation system (Orica i-konTM) was conducted in the summer of 2002. The primary objective of the evaluation blasts was to design shots that would segregate the ore and waste blocks into distinct muckpiles. Due to surface delay burning front limitations, truly effective ore and waste segregation blasting is difficult to accomplish with non-electric initiation systems for all but the most basic of ore geometries. The electronic detonator evaluation blasts produced visible boundaries in post blast muckpiles, identified by troughs or low areas, that closely matched the actual locations of pre-blast ore control flag lines based on blast hole assays. By blasting the ore and waste into distinguishable piles that were flagged and excavated accordingly, it is believed that blast-induced ore loss and dilution was reduced.

Jan 1, 2004