NIOSH Mining Safety and Health Topic

Explosives


Blasting agent fumes studies are done in NIOSH's explosion sphereBlasting is an important part of most mining operations. Between 1978 and 2000, 106 miners were killed and 1,050 were injured by explosives and breaking agents. Through the efforts of government, mine operators, labor, and academia, these numbers have been significantly reduced. In 2001, there were 7 blasting-related injuries and fatalities in the mining industry, compared to 140 in 1978. While blasting has become safer, accidents still occur so continued vigilance is needed. For the past two decades, most explosives-related injuries and fatalities in surface mines occurred when workers were struck by rock, either because they were too close to the blast or rock was thrown much farther than expected. The second leading cause was blasts that shoot prematurely. In underground mines, most explosive-related fatalities were caused by miners being too close to the blast, followed by explosive fumes poisoning, misfires, and premature blasts. Misfires lead to injuries and fatalities as miners try to shoot explosives that failed to detonate in the original blast. Premature blasts occur without warning while blasters are near the explosive-loaded boreholes; the explosive may be initiated by lightning, the impact of explosives being dropped down a dry borehole, or careless handling of the initiating system (blasting caps).

The work in this topic area is supported by the NIOSH Mining Explosives program. See the NIOSH Mining Products page for software, guides, training materials or other items related to this topic.



Overviews

A Review of Recent Accidents Involving Explosives Transport (PDF, 644 KB, 2008)
This article is a review of recent accidents involvng explosives transport both in the United States and outside of the United States.


Data & statistics

Fatal Accidents Due to Flyrock and Lack of Blast Area Security and Working Practices in Mining (PDF, 344 KB, 2003)
This paper briefly describes six representative fatalities due to flyrock and lack of blast area security in coal and nonmetal mines. Several mines were visited to collect information relative to working practices aimed at mitigating blasting hazards. Salient information obtained through these visits is presented

Flyrock Issues in Blasting (http://www.isee.org/tis/Proceed/General/01GENV1/01V117.PDF(PDF, 30 KB, 2001-02)
A compilation of the primary causes of flyrock in surface mining blasting operations and reasons a safe blast area was not secured.

A Summary of Fatal Accidents Due to Flyrock and Lack of Blast Area Security in Surface Mining, 1989 to 1999 (PDF, 264 KB, 2002)
This paper summarizes flyrock and blast area security fatalities from 1989 to 1999 and examines the causative factors. Accident data indicates that flyrock and lack of blast area security were the primary causes of blasting related injuries in surface mining. Fatal injuries due to lack of blast area security were attributed to: failure to clear blast area; failure to follow instructions; inadequate guarding; inadequate blasting shelter; and unsafe location.


Models

Work Principle for Predicting Explosive Toxic Fumes (PDF, 1167 KB, 1998)
Research on applying the work principle to the non-ideal conditions of mining explosives to determine toxic fume production.

Work-Principle Model for Predicting Toxic Fumes of Nonideal Explosives (PDF, 919 KB, 2004-08-01)
The work-principle from thermodynamics was used to formulate a model for predicting toxic fumes from mining explosives in underground chamber tests, where rapid turbulent combustion within the surrounding air noticeably changes the resulting concentrations. Two model constants were required to help characterize the reaction zone undergoing rapid chemical transformations in conjunction with heat transfer and work output: a stoichiometry mixing fraction and a reaction-quenching temperature. The work-principle model yields toxic concentrations for a range of charge formulations, making it a useful tool for investigating the potential hazard of released fumes and reducing the risk of unwanted incidents.


Hazards

Dangers of Toxic Fumes from Blasting (PDF, 83 KB, 2007)
This paper reviews the potential hazards posed by the toxic fumes produced by detonating explosives in surface mining and construction operations. Techniques to protect workers and the public from the potential hazards of explosive-related toxic fumes are discussed.


Measurement & analysis

Behavior of Nitrogen Oxides in the Product Gases from Explosive Detonations (PDF, 158 KB, 2006-01)
In this study, 10-lb charges of blasting agent confined in either thin-wall 4-in-diam galvanized pipe or 4-in schedule 80 stainless steel pipe were detonated in a closed chamber. detonation gases were analyzed for nitrogen dioxide, nitric oxide (NO), ammonia, hydrogen, carbon monoxide, carbon dioxide, nitrogen, oxygen, and methane. Data were evaluated to determine the kinetics of the oxidation of NO to nitrogen dioxide. The information on NO oxidation kinetics provided will prove useful in efforts to model the behavior of NO and nitrogen dioxide in clouds of detonation products near blasting operations.

Blasting-Related Carbon Monoxide Migration Incident in Bristow, Virginia (PDF, 1780 KB, 2004)
A detailed description of blasting-related carbon monoxide migration from a construction site into nearby residential homes.

Chemical and Physical Factors that Influence N0x Production During Blasting: Exploratory Study (PDF, 1147 KB, 2002-02)
Report on a NIOSH study to identify factors that may contribute to nitrogen oxides (NOx) production associated with non-ideal detonation of blasting agents.

CO Migration from Trench Blasting in Amherst, New York (PDF, 1480 KB, 2004)
A general overview of the blasting and CO monitoring of a highway construction project is presented and discussed. The use and effectiveness of residential type CO monitors and multi-gas monitors are discussed.

Factors Affecting ANFO Fumes Production (PDF, 307 KB, 2000-02)
Study of toxic fumes produced by the detonation of various ammonium nitrate/fuel oil (ANFO) mixtures and several cap-sensitive explosives.

Factors Affecting Fumes Production of an Emulsion and ANFO/Emulsion Blends (PDF, 2452 KB, 2001)
Study of toxic fumes produced by the detonation of ANFO/emulsion blends. An extension of previous ANFO fumes production research that includes an emulsion blasting agent.

Field Studies of Carbon Monoxide Migration from Blasting (PDF, 651 KB, 2005)
Describes a small-scale field study to identify key factors that may contribute to the migration of CO through the ground.

Fugitive Carbon-Based Gases: Blasting Related or Not (PDF, 347 KB, 2004)
This paper discusses elements of a stray gas investigation and the analyses necessary to identify the source of a stray gas.

Hazard Evaluation and Technical Assistance Report, HETA-98-0020, Carbon Monoxide Intoxication and Death in a Newly Constructed Sewer Manhole (PDF, 132 KB, 1997-10)
This is a Hazard Evaluation and Technical Assistance Report on a poisoning incident where CO migrated from nearby blasting activities into a new sewer system being constructed.

Impact, Thermal, and Shock Sensitivity of Molten TNT and of Asphalt-Contaminated Molten TNT (PDF, 236 KB, 1996)
Research evaluating the autoclave meltout process to recover TNT from MK-9 depth bombs.

Overlap Probability for Short-Period-Delay Detonators Used in Underground Coal Mining (PDF, 2594 KB, 1985)
Investigation of coal-mine-type short-delay electric detonators to determine the delay accuracy and the probability of overlap between adjacent delay periods.

Removing Booster Influences From Toxic Fumes (PDF, 7800 KB, 1999)
Investigation of the viability of removing the booster influences when ranking the toxic fumes of non cap-sensitive mining explosives.

A Technique for Measuring Toxic Gases Produced by Blasting Agents (PDF, 226 KB, 1997-01)
Traditional techniques for the experimental determination of toxic fumes produced by the detonation of high explosives are not applicable to blasting agents. A facility for detonating large, confined charges in a controlled volume has been constructed at the Pittsburgh Research Center's Experimental Mine.

Technology News 488 - Migration of Blasting Fumes into a Western Pennsylvania Home (PDF, 539 KB, 2001-05)
NIOSH tech news report on an incident where CO generated from blasting at a strip mine migrated through the ground into a nearby home, poisoning the occupants.

Toxic Fume Comparison of a Few Explosives Used in Trench Blasting (PDF, 701 KB, 2003)
Report on NIOSH studies using a 12-foot diameter sphere to identify key factors that may enhance the levels of CO associated with the detonation of several commercial trenching explosives.


Engineering controls

An Analysis and Prevention of Flyrock Accidents in Surface Blasting Operations (PDF, 133 KB, 2004)
Discusses several flyrock injury incidents at surface mines and construction sites and describes some injury mitigation techniques.

Blasting Safety - Revisiting Site Security (PDF, 120 KB, 2005)
This paper examines the factors related to injuries due to inadequate blasting shelters and blast area security, and identifies mitigation techniques.

Evaluation of a Sheathed Permissible Explosive Charge for Open Shooting in Flammable Atmospheres (PDF, 1087 KB, 1982-04)
The Bureau of Mines has developed a prototype nonincendive explosive rock-breaker charge that can be fired unconfined in underground bituminous coal mines without the danger of igniting a flammable atmosphere that might be present.

Protecting Workers From Toxic Fumes Generated by Explosives (PDF, 110 KB, 1999-12)
An article outlining the hazards of carbon monoxide (CO) generated from blasting operations.

Securing the Blast Site to Prevent Blasting Related Injuries: Blasting Safety - Revisiting Site Security (PDF, 567 KB, 2005)
This article examines the factors related to injuries due to inadequate blasting shelters and blast area security, and identifies mitigation techniques.

Short-Delay Blasting in Underground Coal Mines (PDF, 2091 KB, 1986)
Research to determine whether the total elapsed delay time for blasting bituminous coal in underground coal mines could be safely expanded beyond the 500-ms limitation without igniting a methane or methane-coal dust atmosphere. Also reports on safety evaluation of 18" hole spacing for delay blasting in coal relative to misfires.


Training packages

Toolbox Training on Flyrock Awareness
The objective of this toolbox training on Flyrock Awareness is to improve blast safety by providing information about blasting to those who work around blast sites.


Training

Technology News 522 - Blast Area Security: Flyrock Safety (PDF, 149 KB, 2006-12)
NIOSH has released communication products about flyrock safety in the form of informational brochures, flashcards, and toolbox talk materials. These communication tools target the mining and construction industries, and can be used as refresher training for employees and as introductory safety materials for onsite visitors.


Videos

Handling Explosives in Underground Mines
Part construction crew, part demolition crew: underground miners deal with both creation and destruction in a typical day. Though explosives are safer than ever before, caution is still needed when dealing with such a powerful force. This 1998 video teaches new miners basic safety rules to keep from hurting themselves or others while handling explosives.

Blast Area Security
This video provides information about blast area security to those working around blast sites.


Facilities

Bombproof 142
Assessing the quality and performance characteristics of explosive materials.

Explosives Testing Pond
Underwater testing of explosives.

Explosives Testing Site (Plateau)
Explosives testing.

Explosives Testing Site (Upper Quarry)
Explosives testing.

Lake Lynn Experimental Mine
Large-scale explosion trials and mine fire research.


Information gateways

Alcohol, Tobacco, and Firearms (http://www.atf.gov/)

Alcohol, Tobacco, and Firearms (ATF) Explosive Regulations (http://www.atf.gov/regulations/27cfr55.pdf)

ATF Federal Explosives Law and Regulations (http://www.atf.gov/explarson/fedexplolaw/2007edition)

Austin Powder Company (http://www.austinpowder.com/home.htm)

Bureau of Explosives Publications (http://www.boepublications.com)

Crowcon (http://www.crowcon.com/)

Draeger Safety (http://www.draeger.com/ST/internet/US/en/index.jsp)

Dyno Nobel (http://www.dynonobel.com/dynonobelcom/en/global/)

Enerac, Inc. (http://www.enerac.com/)

Energetic Materials Research and Testing Center (http://www.emrtc.nmt.edu)

Federal Bureau of Investigation Laboratory, Explosives Unit (http://www.fbi.gov/hq/lab/html/eu1.htm)

Implosionworld.com (http://www.implosionworld.com/)

Institute of Explosive Engineers (Great Britain) (http://www.iexpe.org/)

Institute of Makers of Explosives (IME) (http://www.ime.org)

International Association of Bomb Technicians and Investigators (http://www.iabti.org/)

International Society of Explosive Engineers (ISEE) (http://www.isee.org)

Mine Safety and Health Administration (http://www.msha.gov)

Mining Resource Engineering Limited (MREL) (http://www.mrel.com/MREL_Home.html)

Occupational Safety and Health (OSHA) Explosive Regulations (http://www.osha.gov/pls/oshaweb/owadisp.show_document?p_table=STANDARDS&p_id=9755)

Orica Mining Services (http://www.oricaexplosives.com/)

PCB Piezotronics (http://www.pcb.com/)

Pennsylvania Department of Environmental Protection (PADEP) Explosive Regulations (http://www.pacode.com/secure/data/025/chapter211/chap211toc.html)

Safety Consulting Engineers, Inc. (http://www.sceinc.com/)

Safety Management Services, Inc. (http://www.sms-ink.com/about_us.html)

Shock Transients Incorporated (http://www.shocktrans.com)

Stressau Laboratory Incorporated (http://www.stresau.com/index.htm)

Testo (http://www.testo.com/)

The Ensign-Bickford Company (http://www.ensign-bickfordcompany.com/)

Page last updated: January 14, 2009
Page last reviewed: January 9, 2009
Content Source: National Institute for Occupational Safety and Health (NIOSH) Mining Division