Securing the Blast Site

to Prevent Blasting 

Related Injuries

Blasting Safety - Revisiting Site Security
 By T. S. Bajpayee, Harry C.Verakis, and Thomas E. Lobb 

This article examines the factors related to 

injuries due to inadequate blasting shelters 

and blast area security, and identifies mitigation techniques. The key concepts are: 

(a) accurate determination of the bounds 

of the blast area, (b) clearing employees 

from the blast area, (c) effective access 

control, (d) use of adequate blasting shelters, (e) efficient communications, and (f) 

training. Fundamentals are reviewed with 

an emphasis on analyzing task elements 

and identifying root causes for selected 

blasting accidents. Mitigating techniques 

are presented along with discussions and 

examples.

Introduction

Domestic consumption of explosives during 2003 was 

approximately 5.05 billion pounds and about 89% (4.5 

billion pounds) was used by the mining industry [USGS, 

2004]. Blasting is a great tool in fragmenting and loosening rock and other materials for easier handling and 

removal by mining equipment. However, blasting creates serious concerns for the mine operators and miners 

in terms of blast area security. 

One thousand one hundred and thirty-one blastingrelated injuries were reported by the mining industry 

during the period 1978-2003 [Verakis & Lobb, 2003 with 

updated data]. Blast area security accounted for 50.1% of 

these injuries followed by premature blast (11.4%), flyrock (10.8%), misfires (9.9%), and fumes (8.5%). Figure 

1 shows the distribution of blasting-related injuries during 1978-2003. 

During 1978-2003, blast area security accounted for 

41% of all blasting related injuries reported by surface 

mines. The corresponding figure for underground mines 

was 56%. The data indicates that injuries from inadequate blast area security are more prevalent in underground blasting. 

Verakis & Lobb [2003 with updated data] analyzed 

more recent data (1994-2003) to assess any changes in 

the role of blast area security. During this period, blast 

area security accounted for nearly 41.6% of all blastingrelated injuries in surface and underground mines. 

Figure 1 shows the distribution of blasting-related 

injuries during 1994-2003. Injuries due to inadequate 

blast area security continue to be a major safety concern. 

The injuries discussed in this article, primarily result 

from failure to identify and clear the blast area, inadequate guarding, failure to communicate or follow instruc­
tions, and inadequate or improper cover. Compliance 

to an effective blast area security protocol plays a key 

role in preventing injuries to miners, visitors, neighbors, 

and trespassers. 

Figure 1. Distribution of blasting-related injuries in the mining industry. 

Blast Area

One of the greatest challenges, which a blaster faces 

in mining and construction blasting, is to accurately 

determine the bounds of the blast area. This is particularly true in geologically disturbed rock. A blaster’s 

decision in estimating the bounds of the blast area is 

greatly influenced by the engineering design of the 

blast, geology of the blast, regulatory requirements, and 

company policy. Schneider [1995] stated that a blaster 

must make an estimate of the maximum possible distance flyrock could travel from a shot. Furthermore, a 

blaster should not assume that a shot being fired will 

behave like other shots previously fired at the same 

operation. 

For surface and underground metal-nonmetal mines, 

Title 30 Code of Federal Regulations (30 CFR) § 56.2 and 

§ 57.2 defines blast area as the area near blasting operations in which concussion or flying material may cause 

injury. The following factors shall be considered to 

determine the blast area: 

• Geology or material to be blasted, 

• Blast pattern, 

• Burden, depth, diameter, and angle of the holes, 

• Blasting experience of the mine, 

• Delay systems, powder factor, and pounds per 

delay, 

• Type and amount of explosive material, and 

• Type and amount of stemming. 

The Federal Office of Surface Mining (OSM) regulations [30 CFR § 816.67 and 817.67] help to characterize 

the bounds of the blast area by specifying that flyrock 

shall not be cast from the blasting site-

• More than one-half the distance to the nearest 

dwelling or other occupied structure, 

• Beyond the area of control required under 30 CFR § 

816.66(c), or 

• Beyond the permit boundary. 

Similar requirements are prescribed by many coal 

mining states such as Colorado, Illinois, Kentucky, New 

Mexico, Ohio, Pennsylvania, Utah, Virginia, West 

Virginia, and Wyoming. 

The bounds of a blast area should be adequately 

determined for each blast. Flyrock could travel beyond 

an inadequately defined blast area and cause injury. In 

Campbell County, TN, flyrock traveled beyond the blast 

area resulting in a fatal injury to a motorist traveling on 

interstate 75 [Shea & Clark, 1998]. The bounds of the 

blast area were not adequately determined for this blast. 

In a coal mine blast, flyrock traveled 900 feet and landed beyond the permit boundary causing a fatal injury 

[MSHA, 1990a]. During a construction blasting operation 

near Marlboro, NY, flyrock was showered on passing 

motorists on Route 9 W about 180 feet from the blast pit. 

This incident resulted in property damage and injury. 

There are numerous instances where the bounds of the 

blast area were not accurately determined, resulting in 

injury, or property damage. There are many cases of 

close calls where accidents were narrowly missed. 

Blast area security in underground mines is much 

more complex than surface blasting. It requires a thorough understanding of ventilation, roof characteristics, 

and the roof control plan of the mine. The bounds of 

the blast area need to be adjusted accordingly. Blasting 

could cause ground fall in adjacent entries, and exposure 

to smoke, dust, or toxic fumes. All employees must be 

removed from such adjacent entries or other affected airways. Post-blast roof fall and exposure to fumes have 

caused several accidents. 

Fundamental task-elements of a blast area 

security system

A blast area security system is the means by which a 

mine operator prevents injury to people or damage to 

equipment when a scheduled blast is detonated [Fletcher 
& D’Andrea, 1987]. Most blasting accidents in surface 

and underground mines occur during scheduled blasting 

and are due to inadequate blast area security. MSHA 

accident data reveal that the blasting crew and blasters 

often suffer serious injuries due to inadequacy of the 

shelter used for protection from blasts. 

The functional task-elements of a blast area security 

system are (a) estimate the flyrock zone based on shot 

conditions, and add a factor of safety to determine the 

bounds of the blast area, (b) clear all employees, contractors, and visitors from the blast area, (c) post guards 

at the access points to prevent unauthorized entry, (d) 

use adequate blasting shelters for employees whose 

presence is required in the blast area, and (e) maintain 

effective communication with guards, mine foreman, 

and other employees. 

Determination of the bounds of the blast 

area 

Correct assessment of the bounds of the blast area is 

the first step in ensuring safety. The blaster should 

determine the bounds of the blast area after caref

consideration of information such as the driller’s 

ul 

log, blasthole deviation data, laser-profile data, 

slant of the holes, blasthole loading data, condition of the highwall, presence of overhangs, back-breaks, voids, weathering, 

and variations in the local geology. A 

blaster usually understands that in a 

given surface or underground mine, 

blast area could vary from shot to shot.

There are many occurrences of flyrock landing beyond the property or permit boundary in 

surface blasting. Such occurrences demonstrate 

incorrect determination of the bounds of the blast 

area. Flyrock from a limestone quarry traveled about 

930 ft and fatally injured a resident who was mowing 

grass on his property [MSHA 1990b]. 

In underground mining situations, the mine roof conditions, ground support system, and ventilation are 

important factors in determining the extent of the blast 

area. In an underground gold mining operation in 

Nevada, blasting in a drift caused a roof fall in another 

drift situated about 25 ft below the blasted drift. When 

the blast occurred in the upper drift, about 40 to 50 tons 

of material above the anchorage zone, supported by 6­

ft roof bolts, fell as a result of the blast. 

Blasting often causes redistribution of stress in pillars 

and roof area. The blast area should be extended 

beyond any suspected zones of weakness in roof strata. 

Often, blasting has caused roof falls in metal/nonmetal 

mines particularly in weak roofs. The blast area should 

be extended to mitigate such hazards. Roof and rib conditions need to be checked before any employee is 

allowed to enter the area. 

Determining the bounds of a blast in an underground 

coal mine is an especially important task. Serious 

injuries and fatalities have occurred when a blast shoots 

through into an adjacent entry. In an underground coal 

mine in Floyd County, KY, three miners were injured 

when a face blasted into an outby crosscut [MSHA, 

2003]. 

Warning! 

Explosives in Use 

Blasting Area

Do Not Enter 

Removing employees from the blast area 

All employees must be cleared from the blast area 

and removed to a safe location prior to any scheduled 

blasting. All equipment in the blast area should be 

removed or protected from flyrock damage, if possible. 

An accounting must be made for all employees to make 

sure that no one is left behind in the blast area. 

Arrangements should be made to ensure that no one can 

return back to the blast area prior to sounding an “allclear” signal. Several accidents were caused because a 

blaster or a crew member was within the bounds of the 

blast area when the shot was fired. In a limestone mine, 

a blaster and a crane operator were standing on a top 

bench about 120 feet from the nearest blasthole. Upon 

firing the shot, the crane operator was fatally injured by 

flyrock [MSHA, 1994]. In a nonmetal mine, a visitor sustained serious injuries and a blaster-helper was fatally 

injured by flyrock [MSHA, 1990c]. They were within 150 

feet from the edge of the blast. 

In many underground mines, blasting is scheduled during a non-production shift when no one, 

except the blast crew, is present underground. 

In addition to mitigating blasting hazards, this 

77.1303 (h) requires that “All persons shall 

be cleared and removed from the blasting area 

procedure aids in providing additional 

time for clearing dust, smoke, and

fumes from the underground workings.

For surface coal mines, 30 CFR § 

unless suitable blasting shelters are provided to 

protect men endangered by concussion or flyrock 

from blasting.” For underground coal mines, 30 CFR § 

75.1325 (c) requires that “All persons shall leave the 

blasting area and each immediately adjacent working 

place where a hazard would be created by the blast, to 

an area that is around at least one corner from the blasting area. The qualified person shall ascertain that all persons are a safe distance from the blasting area.” The 

onus of determining the safe distance rests on the qualified person, who in most cases is the blaster. 

In brief, the message is “Be alert and share information; know the blasting time, blast area and 

clearing procedure; and do not enter the blast area 

until an “all-clear” signal is sounded.” 

Access control 

To prevent unauthorized entry, guards should be 

posted at all access points leading to the blast area. 

Guards should physically remain at their duty stations 

until an “all-clear” signal is sounded. The guards must 

be attentive at all times to ensure the security of the 

blast. Additionally, barricades may be erected with signs 

in bold letters such as “Warning! Explosives in Use, 

Blasting Area, Do Not Enter” may be posted at all 

access points. 

For surface and underground metal/nonmetal mines, 
30 CFR § 56.6306 (e) (3) and 57.6306(e) (3) require that 

“All access routes to the blast area shall be guarded or 

barricaded to prevent the passage of persons or vehicles.” 30 CFR § 56.6306 (a) and 57.6306(a) require that 

“When explosive materials or initiating systems are 

brought to the blast site, the blast site shall be attended; 

barricaded and posted with warning signs, such as 

“Danger,” “Explosives,” or “Keep Out;” or flagged 

against unauthorized entry.” 

The OSM regulations in 30 CFR § 816.66 (c) and 

817.66 (c) require that “Access within the blast area shall 

be controlled to prevent presence of livestock or unauthorized persons during blasting and until an authorized 

representative of the operator has reasonably determined that - (a) No unusual hazards, such as imminent 

slides or undetonated charges, exist; and (b) Access to 

and travel within the blasting area can be safely 

resumed.” 

Several accidents were related to inadequate accesscontrol to the blast area. A neighbor was fatally injured 

when he inadvertently entered the blast area through an 

access trail before the blast [MSHA, 1999]. Guards were 

not posted for access control. The access trail was in a 

wooded area and not visible from the firing station. This 

incident underscores the need for an effective access 

control protocol. 

In a coal mine incident, a guard was posted to prevent entry to an access road leading to the blast area. 

Immediately before the blast, the guard left his post and 

went to the mine office for a brief visit. No barricade or 

notice of impending blasting was posted at this access 

road. In the meantime, a drill operator and a dozer 

operator, unaware of the impending blasting, entered 

the pit area in a pickup truck. Upon firing the shot, the 

dozer operator was fatally injured and the drill operator 

sustained injuries [MSHA, 1989a]. This accident could 

have been prevented by proper access control. 

In another coal mine, a fatal accident occurred 

because an employee, who was cleared from the blast 

area, managed to return to the coal bench a few minutes 

before the scheduled blast. No one including the blaster 

noticed the employee returning to the coal bench. The 

victim was about 15 feet from the toe of a 43-feet highwall. Upon firing the overburden shot, the employee 

and his pickup truck were covered under a pile of blasted material [MSHA, 1989b]. It is important to make certain that no one can return back to the blast area until 

an “all-clear” signal is sounded. 

Bennett’s [1981] study indicated that access control 

and blast guarding suffer from poor procedures rather 

than from a lack of advanced technology. Management 

and employees should diligently strive to formulate and 

follow best site-specific procedures and policies to prevent injuries. A good access control procedure, upon 

implementation, can prevent injuries from blasting. 

Blasting shelter

MSHA accident data indicate that blasters and helpers 

often suffer injuries due to lack of adequate shelter from 

a blast. The blaster and blasting crew are typically closer to a blast than other employees and need to use shelter that will provide complete protection from flyrock that 

may be projected from a blast. Flyrock from a blast can 

travel vertically and does not fall like gentle rain. Flyrock 

can also travel along a horizontal path and become a 

deadly projectile. 

Unfortunately, there are too many instances that illustrate the use of inadequate protection from flyrock that 

was generated by a blast. For example, a blaster fired a 

charge inside a water well hole. A piece of flyrock traveled 208 feet and fatally struck the blaster on the head. 

The blaster was standing in the open and did not use 

some means of protection such as a blasting shelter. 

In another incident in Pulaski County, KY, a blaster 

having sixteen years experience, took shelter behind a 

metal magazine of approximate size 4-feet high by 4-feet 

wide by 4-feet long and fired a charge. A piece of flyrock 

weighing about 15 pounds traveled 150 feet and fatally 

struck the blaster on the head [Schneider, 1995]. This 

accident could have been prevented by using an adequate blasting shelter. 

Figure 2 shows a blasting shelter used at a surface 

limestone mine in Southwestern USA.

Figure 2. Blasting shelter used at a surface limestone mine in 

southwestern United States. 

 The shelter was 

constructed by the mine’s personnel. Another example 

of a blasting shelter used at a surface limestone mine in 

Ohio is shown in Figure 3. The mining company 

requires that this type of blasting shelter be used for protection from a blast. The blast shelter is mounted on 

skids for ease of transportation and is constructed of steel 

that is 3/8-inch thick. The use of specially designed blasting shelters can provide the protection needed to prevent 

a person from being struck by flyrock. In the international sphere, a more sophisticated blast shelter has been 

designed by two Queensland, Australian inventors 

[Queensland Government Mining Journal, May 2001]. 

The shelter, which is cylindrical and constructed of 5/8­

inch thick steel, is mounted on a rubber tired trailer. 
Figure 3. Blasting shelter at a surface limestone mine in Ohio. 

Light buildings, pickup trucks, and other vehicles 

which are often used as covers, have been penetrated by 

flyrock [Schneider, 1996]. During a coal mine blast, a 

blaster positioned himself under a Ford 9000, 21/2-ton 

truck, and fired the shot. A piece of flyrock traveled 

about 750 ft and fatally injured the blaster under the 

truck [MSHA, 1992]. This accident could have been prevented by using an adequate blasting shelter. A safe 

location and sufficient cover is critical to a blaster’s protection if the firing lines are not long enough to be 

beyond the flyrock range [Schneider, 1996]. Some blasting operations use a remote controlled firing system to 

permit blasters to stay out of the blast area. 

In a construction blast, an employee standing behind 

a front-end loader was struck by flyrock. The employee 

suffered trauma to his neck and lacerations to his face 

[OSHA, 1992]. This accident could have been prevented 

by using an adequate blasting shelter. 

The Chief Inspector of Mines in Queensland, 

Australia, reported that a blaster was standing behind a 

steel hopper while video-taping a toe shot in a metalliferous quarry. Flyrock traveled about 246 feet and seriously injured the blaster. The blaster lost his right eye, 

his cheek bone was shattered, and his jaw was broken. 

This accident could have been prevented by using a 

proper blasting shelter. 

Effective communication

Effective communication is a key element in preventing blasting injuries. Blasting in mining operations is a 

complex process and requires coordination and communication between (a) driller and blaster, (b) blaster 

and crew members, (c) blaster and other miners, and (d) 

blaster and mine management, among others. Failure of 

effective communication may result in fatalities and serious injuries. Workers and visitors should be informed 

about the blasting signals, evacuation procedure, location, and timing of a scheduled blast on a daily basis. 

Many surface operations schedule blasting events 

between sunrise and sunset. In many underground 

operations, blasting is often scheduled when no one, 

except the blast crew, is present in the vicinity. 

Audible signals, such as sirens, whistles, or horns 

mounted on a vehicle, are used in many operations to 

caution employees, visitors, and neighbors about a 

scheduled blasting event. Enough time should be provided to facilitate orderly evacuation of all personnel, 

whose presence is not required, from the blast area. 

For surface and underground metal-nonmetal mines, 

30 CFR § 56.6306 (f) (1) and 57.6306 (f) (1) require that 

“Ample warning shall be given to allow all persons to be 

evacuated.” For surface coal mines, 30 CFR § 77.1303 

requires that “ample warning shall be given before blasts 

are fired.” The OSM regulation in 30 CFR 816.64 (a) 

requires that “The operator shall publish the blasting 

schedule in a newspaper of the general circulation in the 

locality of the blasting site at least 10 days, but not more 

than 30 days, before beginning of a blasting program.” 

30CFR 817.64 (a) requires that “The operator shall notify, in writing, residents within 1/2 mile of the blasting 

site and local governments of the proposed times and 

locations of blasting operations.” 

Unified approach for mitigating injuries

Brnich & Mallett [2003] advanced the concept of conducting a hazard-risk assessment for preventing mining 

injuries. A site-specific hazard-risk assessment based on 

the probability of an event and its severity is an excellent 

tool for the blasting community. Blasting releases a 

tremendous amount of energy within a very short time 

and is considered a hazardous operation. An analysis of 

site-specific risk factors will help in understanding and 

mitigating possible hazards. A site-specific hazard-risk 

matrix should be drawn up and discussed during 

blaster/miners job assignments, safety discussions, and 

training sessions. 

An Australian document [DR 04062, 2004] issued for 

public comment accentuates the risks of blasting and 

recommends that “...whenever explosives are to be used 

that a competent person(s) carry out a detailed risk 

assessment to identify all foreseeable potential hazards 

and take appropriate steps to eliminate or reduce the 

likelihood and mitigate the severity of any effects so that 

risks are at an acceptable level.” The Australian document accentuates Brnich & Mellett’s [2003] hazard-risk 

assessment concept. 

Brulia [1993] reported that about 80-90% of all accidents are caused by human factors, and listed five salient 

elements which contributed to these accidents: 

• Negligence - failure to observe safety rules and 

instructions, 

• Hasty decisions - acting before thinking usually leading to hazardous shortcuts, 
This paper was presented by the authors at the ISEE’s 31st

Annual Conference on Explosives and Blasting Technique in

February, 2005 in Orlando, FL.This paper has been updated

from its original version.The opinions and ideas expressed are

not necessarily those of the International Society of Explosives

Engineers or the editorial/publishing staff of the Journal of

Explosives Engineering.Your response in the form of a letter to

the editor is encouraged.See “The Proceedings of the 31st

Annual Conference on Explosives and Blasting Technique”for

full text and references for this paper.

• Inadequate instruction - untrained or improperly 

trained personal, 

• Overconfidence - taking chances, 

• Lack of planning - insufficient understanding of a 

blasting situation. 

Safety professionals often use a multi-faceted 

approach for injury prevention. This includes intervention techniques conducted through (a) training and continuing education of miners and blasters, (b) site-specific policies and procedures, and (c) engineering controls. 

Commitment to safety by the blaster, blasting crew, other 

miners, and the mine operator is the most essential 

ingredient for injury prevention. 

Training and continuing education

Training and continuing education play a vital role in 

building up and enhancing the knowledge base of 

employees. It helps the blaster, blasting crew, and other 

miners to develop a higher level of awareness to identify hazards and apply proper mitigating techniques. Sitespecific training relative to the bounds of the blast area, 

non-work zone beyond the blast area, blast guarding, 

access control, and clearing protocol should be made 

available to all new employees. A detailed discussion of 

hazards associated with the transport and use of explosives should also be included in the overall training program. Drillers should be trained to search for any geological anomaly and report such information to the 

blaster. Blasters should be trained to consider all available data to determine the bounds of the blast area for 

each shot. The level of training, experience, and attitude 

of explosive handlers is crucial to the attainment of higher blasting safety [Brulia, 1993]. 

The ISEE has made available several state-of-the-art 

training modules for mining and construction blasting. 

The MSHA’s National Mine Health and Safety Academy 

also provides training and material for surface and 

underground blasting. Regular refresher training should 

be made available to all explosive handlers. OSM and 

many state regulations require that blasters working in 

surface coal mines be examined and certified. 

It is important to conduct a post-blast analysis of each 

shot to determine if the shot performed as planned. 

And, if there are any deviations, the blaster should look 

for the reasons for such deviations. All near miss incidents should be critically examined. Training should be 

aimed at greatly augmenting the blaster’s knowledge 

and confidence level. The blaster should be proactive 

and understand that “The challenge is defined, the solution is clear, the need is immediate, and success depends 

on the blaster.” 

Site specific policies and procedures 

Mine operators should develop site-specific safety 

procedures consistent with company policy, local, state 

and federal laws. The procedure should address all 

activities such as equipment selection, blast planning, 

determining the location of blastholes, pre-blast examination of face and high wall, evaluation of driller’s log, 

loading and priming of explosive charge, determining 

the bounds of the blast area and non-work zone beyond 

the blast area, evacuation and clearing protocol of 

employees, personnel accounting system, examination 

and guarding blast area, blasting time and signal, access 

control to blast area, and communication protocol. 

Many mine operators have standardized their blast 

guarding protocol. Pre-blast planning and discussion 

with crew members reinforce confidence and provide an 

avenue for good cooperation. Such discussion and planning forums also provide an opportunity to ask questions and resolve any doubts or misconceptions. 

As a matter of policy, many underground mines 

schedule a blasting event for the evening or night shift 

when no one, except the blasting crew, is present underground. Some operators have installed a remote firing 

system to remove the blaster from the blast area. 

Engineering controls 

Blasting safety can be greatly enhanced by good engineering controls and feedback mechanisms. Engineering 

controls should be well understood and closely followed 

by the blasting community. Dick et al. [1983] and 

Fletcher & D’Andrea [1986] advocated the use of portable 

blasting shelters. The shelter may be cylindrical in shape 

and constructed of heavy steel to withstand any possible 

impact from flyrock. The portable shelter may be mounted on wheels or skids for ease of moving from one blast 

area to another. The blaster enters the shelter and closes the door prior to firing the shot. 

Commitment to safe blasting practices by the mine 

operator, blaster-in-charge, blasting and drilling crew and 

other miners and affected persons is an essential ingredient in injury prevention. Many mines have developed 

excellent site-specific blast guarding systems. An individual, with experience and knowledge in blasting, 

should oversee the entire process and advise the blasting personnel accordingly. This individual may be a 

blasting superintendent, blasting foreman, blasting engineer, or blaster-in-charge. This person should make sure 

that all relevant policies and procedures are followed, 

and in case of any discrepancy that corrective action is 

appropriately taken.