Reducing non-contact electric arc injuries: An investigation of

behavioral and organizational issues

Kathleen Kowalski-Trakofler ⁎, Edward Barrett

Received 29 November 2005; received in revised form 30 April 2007; accepted 16 June 2007

Available online 12 October 2007

Abstract

Problem: It is estimated that 5 to 10 arc flash explosions occur in electric equipment every day in the United States. In the mining industry

the largest single injury category of electrical injuries are caused by non-contact electrical arcs. Method: This investigation progressed in

two phases: (a) 836 Mine Safety and Health Administration (MSHA) reports of electric arcing incidents that occurred over a period of

11 years were reviewed, and (b) personal interviews were conducted with 32 individuals. A theoretical Safe Job Performance Model guided

the study. Results: Behavioral dimensions were identified and included the effect of worker experience, judgment and decision-making

ability, behavioral and organizational controls, and safety culture. Summary: The National Institute for Occupational Safety and Health

(NIOSH) conducted an investigation of behavioral components associated with arc flash incidents and developed recommendations for

interventions based on findings. Impact on Industry: This study fills a vacuum in electrical training with a focus on the organizational

and behavioral aspects of arc flash incidents. The research is cross-cutting in its scope, in that the results apply not only to mining and

construction, but many other industries employing electricians. Although the majority of mine electrical injuries are the results of burns

from electrical arcs, few miners are aware that such a hazard exists. A safety training program, which includes a video and an instructor's

discussion guide, was developed for electricians based on this study's findings. “Arc Flash Awareness” was released in 2007 (DHHS NIOSH

Publication No.2007-116D) and is available through 1-800 CDC INFO. Phone: 1-800 232-4636 or email cdcinfo@cdc.gov. It is also

available from MSHA at MSHADistribution@dol.gov or 304-256-3257 (DVD-576). Private industry is producing Portuguese and Spanish

language translations.

National Safety Council and Elsevier Ltd. All rights reserved.

Keywords: Arc flash; Electrical safety; Judgment and decision-making; Safety behavior; Mining

1. Introduction

An electric arc results from the release of electrical energy

through the air when high voltage exists across a gap

between conductors. Staged tests using mannequins at the

Paul Gubany High Power Laboratory in 1996 repeatedly

demonstrated that electrical arcs are highly unpredictable

and variable in occurrence, energy, path, and duration (Jones

et al., 2000).

Arc faults give off thermal radiation and bright, intense

light that can cause burns to the body, especially to the skin

and eyes. Next to the laser, the electric arc is the hottest event

on earth, with recorded temperatures as high as 35,000° F

(McCabe, 2005). High-voltage arcs can also produce a considerable pressure wave by rapidly heating the air and producing a blast that may exceed 200 lbs/sq ft (978 kg/sq m).

This pressure burst can send molten metal droplets from

melted copper and aluminum components in electrical

equipment great distances at extremely high velocities. In

addition to direct personal injury from these hot metals, arc

blasts can throw a worker against nearby objects or walls,

causing secondary injuries such as blunt force trauma, cuts,

and abrasions. The impulse sound wave near the unprotected

ear can also result in temporary or permanent traumatic

hearing loss.

“Non-contact” arc flash burns refer to electrical burn

injuries without accompanying electric shock. The person

receiving the arc burn never actually contacts an energized

electrical conductor. The burn occurs, therefore, when the

Journal of Safety Research 38 (2007) 597–608

www.nsc.org

⁎ Corresponding author.

E-mail address: kkowalski@cdc.gov (K. Kowalski-Trakofler).

www.elsevier.com/locate/jsr

0022-4375/$ - see front matter. National Safety Council and Elsevier Ltd. All rights reserved.

doi:10.1016/j.jsr.2007.06.004
worker is exposed to sufficient electromagnetic radiation

from an electric arc. The radiation covers a wide band of

the electromagnetic spectrum, from the infrared and visible range to well beyond the ultraviolet. The burn can range

from a mild reddening of the skin (1st degree) to complete

destruction of skin, underlying muscle, and connective tissue (3rd degree) (Capelli-Schellpfeffer, 2004).

The hazards of a non-contact electric arc flash are present

at most industrial workplaces. CapSchell, Inc. estimates that

5 to 10 arc flash explosions occur in electric equipment every

day in the United States (Fischer, 2004). In the mining

industry, during one recent 12 year period, 36,373 lost work

days were recorded for all electrical injuries. The largest

single injury category within this total was non-contact electrical arc injury. These incidents resulted in three fatalities,

more than 12,000 lost work days (one-third of the total), and

an average of 21 lost work days per incident (KowalskiTrakofler et al., 2003).

Personal accounts from electricians also note that many

workers have experienced some degree of exposure to an

electric arc flash during the conduct of their work. However,

because these occurrences did not result in an injury, they were

not reported. Explanations for escaping injury have ranged

from “pure chance” to practicing proper work procedures, such

as using personal protective equipment (PPE).

The population of workers who may be affected by

electric arc flashes could be on the rise. In 2002, the U.S.

Department of Labor reported there were 659,000 electricians on the job. Projected growth of the number of jobs

available by 2012 is an estimated 814,000 electricians on the

job. This is higher than other similar technical professions.

With this increase in electrical workers and the fact that

non-contact arcing incidents can result from human error

as well as from equipment malfunctions, it may be inferred

that accidents related to human behavior could also be on the

rise.

Non-contact arcing incidents can be spontaneous, such as

in the following example:

An electrical foreman and an electrician had just

replaced a 480-volt circuit breaker panel with a 1000-

volt circuit breaker panel. Following this, the 7200-volt

transformer power was re-energized; however, the circuit

breaker could not be energized. The electrician began to

look at the ground check relay as the source of the

problem when an electric arc occurred. After the smoke

cleared, it was observed that the 1000-volt circuit

breaker panel was leaning outward as it had been left

unbolted by the foreman and the energized line side 995-

volt connections had contacted the transformer frame.

This produced an electrical arc that resulted in serious

burns to both hands and face of the electrical foreman.

In addition, non-contact arcing incidents can result from a

worker inadvertently bridging electrical contacts with a

conducting object. Other causes of arc flash hazards may

include actions such as dropped tools and the build up of

conductive dust and corrosion. Arcing faults can also occur

with direct current, such as mine DC trolley systems or

batteries (Hall, Myers, & Vilcheck, 1980).

Standards for protecting workers against the hazards of an

arc flash are included in NEC 2002 (National Electric Code);

IEEE Standard 1584 (Institute of Electrical & Electronic

Engineers); OSHA 29 CFR 1910 (Occupational Safety and

Health Administration); and NFPA 70E (National Fire

Protection Association). NEC 110.16 requires arc flash

warning labels to raise the level of awareness of electrical arc

flash hazards. IEEE Standard 1584 addresses arc flash

calculations for arcing faults, incident energy, and flash

boundary. OSHA requires that “live” parts greater than

50 volts to ground be deenergized unless the employer can

demonstrate that deenergizing introduces additional hazards

or is infeasible. In the 1970's, OSHA requested the NFPA to

develop a standard for electrical safety for workers. The

latest edition of NFPA 70E was completed in 2004. It is the

most widely applied electrical safety standard for employee

workplaces today. Most notably, it is the first standard to

specifically include arc flash PPE in work practice requirements, as it contains the most protective PPE requirements in

the world. Among its many safety practices, it proposes

training for all workers exposed to potential arc flash or

electrical shock hazards. This includes both task-qualified

workers as well as electrically unqualified workers.

OSHA enforces NFPA 70E under the “General Duty

Clause” in the 29 CFR 1910 (Code of Federal Regulations),

which requires employers to furnish a workplace that is free

from recognized hazards that may cause death or serious

physical harm. According to this mandate, training is

required for unqualified as well as qualified employees.

This training is left to the employer to administer and can be

given on the job or in the classroom. In effect, all employees

who face the risk of electrical injury are required to be

trained. The strategy found in NFPA 70E includes training

for all workers exposed to potential arc flash hazards. This

includes operators who may be “task qualified” to operate a

disconnect, electrically unqualified workers, and office

personnel. All are required to be trained in the basics of

electrical safety to prevent unqualified persons from entering

live work and arc flash zones (Hoagland, Shinn, & Reed,

2004a,b).

Commercially available electrical training programs

generally focus on technical skills, instrumentation, safe

operating procedures, and personal protective equipment.

Protective equipment, including clothing, is one way of

preventing arc flash injury. In recent years, much effort has

been applied to various types of flame-resistant clothing and

to determining weights and construction of natural fibers that

resist ignition. In short, the level of protection must match

the category of the hazard and, in addition to thermal

protection, the PPE system must also be comfortable and

durable (Laverty, 2001). Accepted PPE includes flameresistant clothing, flash suits (for high-energy arc exposure),

flash suit hoods, insulating gloves, and insulated tools. These

598 K. Kowalski-Trakofler, E. Barrett / Journal of Safety Research 38 (2007) 597–608
are in addition to the normally used hard hat, safety shoes,

safety glasses, and hearing protection. Face shields, which

are generally protective against arc hazards, have also

become available for workers. Some negative factors

associated with face shields include decreased peripheral

vision, increased heat, and worker discomfort. At any energy

level, nevertheless, face shields can help protect workers

from much of the flying metal particles produced by the arc

(Hoagland, 1996).

Protective clothing, though, does not take the place of

proper safety training. Michael Enright, an executive with a

commercial supplier of flame-resistant clothing stated that,

“Safety equipment should be the last line of defense. There

are a number of things that can be done on the front end

from the initial engineering design of the equipment, to the

maintenance of the equipment, to the training of the individual who operates the equipment” (Naso, 2004, p.44).

Left out of most training programs, however, is instruction

on individual and organizational behavior that attempts

to influence workers' and employers' attitudes, beliefs, or

behaviors.

There is a growing body of research that indicates job and

organizational level factors have a powerful influence on safe

behavior and the occurrence of accidents/injuries (DeJoy,

Gershon, & Schaffer, 2004). One such factor is safety climate

or safety culture, which is defined as the shared perceptions of

workers about the level of safety in their workplace. Employee

perceptions about safety are important because workplace

injuries have been correlated with safety climate, such that

organizations with strong safety climates consistently report

fewer injuries than organizations with weak safety climates.

There are several key factors associated with a safe

workplace. A safe workplace typically features strong management committed to occupational safety programs where

safety is integrated into the structure of the organization

and there is adequate support for the safety manager. Also,

in safe workplaces, safety performance is assessed periodically, and employees receive feedback on their performance. Another important factor associated with a safe

workplace is the use of experienced workers to train younger

workers in safety procedures and policies along with worker

involvement in safety activities, such as worker safety tool

talks before shift and joint labor/management safety committees. Safe work environments emphasize housekeeping

and workplace cleanliness. In addition, previous studies have

shown that younger workers as opposed to older workers

have a higher frequency of accidents. However, older workers tend to have more severe accidents and are away from

work for longer periods of time as a result (Fotta & Bockosh,

2000).

Given the rising number of incidents, a multi-disciplinary

team of NIOSH researchers led an investigation of noncontact arc flash incidents by studying various individual and

organizational behavioral aspects of past incidents. This

paper identifies many of these behavioral characteristics and

proposes training interventions, which, if eventually developed into instructional exercises, could reduce the frequency

and severity of arcing incidents.

2. A Model for Safe Job Performance

This study is part of a larger, ongoing NIOSH project in

which engineering solutions are being investigated to limit

arc flash incidents. To coordinate the overall effort of the

project, the authors developed a theoretical Safe Job

Performance Model. The model, illustrated in Fig. 1,

Fig. 1.

K. Kowalski-Trakofler, E. Barrett / Journal of Safety Research 38 (2007) 597–608 599
combines engineering controls with administrative and

behavioral components along with specific skills. The core

of the model is the safety climate or the work environment of

the company or organization. Making up this core are six

components that serve as a foundation to support both the

organization and the individual to ensure safe job performance. They include engineering controls, administrative

controls, behavior controls, technical skills, knowledge, and

judgment and decision-making ability.

Engineering Controls, or interventions, are physical manipulations of the sources of the hazard or the manner of

exposure to the hazard. Examples include controlling noise,

chemical exposure, heat, erecting barriers, positioning switches

for safer use, and redesigning electrical tools and equipment.

Administrative Controls are initiatives by management to

modify a work process or exposure. Examples of administrative interventions might be developing a standard

operating procedure, and adjusting work practices such as

job rotation or better shift schedules. Also, training is

sometimes considered an administrative intervention.

Behavioral Controls focus on influencing workers' and

employer's attitudes, knowledge, belief, or behaviors

concerning work hazards or issues of worker health.

Examples include training workers to wear PPE, implementing behavior modification techniques such as feedback to

instill safer behavior, and promoting programs to encourage

worker health, such as stop-smoking plans.

Technical Skills refer to the hands-on skills and abilities

needed to get the job done and complete the electrical task

successfully. Technical skills explain “how” a worker does

the job.

Knowledge refers to the basic information needed in order

to understand the process of the electrical task. Knowledge is

an important underpinning of safe job performance. Workers

need to understand the task within the context of the overall

job, in addition to having the skills to perform the task.

Judgment and Decision-making refers to the workers'

ability to make sound and safe decisions. Most electrical

training programs today include the important subject areas

of “technical skills” and “knowledge.” Thus, the addition of

administrative and behavioral controls, and judgment and

decision-making ability can enhance the effectiveness of

these training efforts. This model may have application not

only in the development of a training program, but also as a

tool to evaluate an electrical safety program. NIOSH reports

that program evaluation is a key issue in training. NIOSH

researchers note that during the past 40 years, knowledge of

the causes of work-related disease and disability has grown

dramatically, however, “ways to evaluate occupational

health and safety interventions is sparse” (Goldenhar &

Schulte, 1996).

3. Method of Study

The investigation was conducted in two phases. Phase

One involved a review of 836 MSHA narratives of electric

arc incidents that occurred in the mining industry over an

11 year period. Phase Two followed with 32 personal

interviews with victims of or witnesses to a non-contact

electric arc event.

3.1. Phase One

3.1.1. Subjects

The subjects were 836 individuals who experienced an

arc flash incident between 1990 and 2001, as reported to the

U.S. Mine Safety and Health Administration (MSHA). The

Code of Federal Regulations 30 Part 50 mandates mine

operators and independent contractors, whose employees

perform certain types of work on mine property, to file a

Mine Accident, Injury and Illness Report for reportable

incidents within 10 working days after the incident or

diagnosis. The information reported includes demographics

of the injured/ill worker such as age, sex, years of total

mining experience, and years of experience at current mine,

as well as information related to the mine location where the

incident occurred, days away from work, days of restricted

work activity, source of the injury, body part(s) injured, and a

narrative description of the incident. The subjects in this

study's average age at the time of the incident was 39 years

and their average mining experience was 14 years. Their job

titles, collapsed from 120 different MSHA database

designations, fell into one of the following three categories:

laborer; technical; or supervisor.

“Laborer” includes rank-and-file workers, such as general

laborers and equipment operators; “technical” refers to

mechanics, electricians, and engineers; and “supervisor”

includes production foremen, electrical foremen, maintenance foremen, and other supervisory personnel.

Approximately 30% of the subjects in the population

were identified in the laborer category; 54% were identified

in the technical category; and 14% were identified as

supervisors. Subjects had been in the technical job title for an

average of 10 years when the reported arc incident occurred.

3.1.2. Narratives

In the written reports MSHA mandates of all “reportable”

incidents at every mine in the United States there is a narrative

written by someone at the mine describing the incident. The

quality of the information varies widely, from highly detailed

to sketchy. These three examples show the nature of some of

the information recorded for arc flash incidents:

(Incident 1) “Employee was tightening battery terminal

on truck when the wrench he was using made contact with

metal box. The wrench when shortened made contact with

employee ring and he received third degree burn on ring

finger.”

(Incident 2) “Disconnect flashed when turning off”

(Incident 3) “The ee used ether to clean the contact points

instead of the contact cleaner as provided. Subject is a

certified electrician. He was wiring the load side of a

600 K. Kowalski-Trakofler, E. Barrett / Journal of Safety Research 38 (2007) 597–608
400 amp circuit breaker. Evidently, the ground lead came

into contact with the A&B phase leads causing an arc and

flash when power was applied to the breaker”

In narratives such as these, information relating to

behavioral characteristics is clearly limited, so in order to

gain any insight into personal conduct of the victims, interpretations and situational judgments had to be made. To this

end, a study team consisting of a psychologist, a sociologist,

and several mining engineers read the accident reports and

discussed conflicting understandings and opinions expressed

in the narratives. After a pilot study of 50 narratives each, the

team developed an evaluation criteria to apply to the narratives

to tease out useful behavior related data. Employing their

collective expertise, two principal categories were established,

namely Organization of Work and Activity.

3.1.3. Criteria

The first principal category, Organization of Work, refers

to the categorization of incidents based on key elements that

contributed to the incident. Three elements were identified

by the study team. First, if it was determined that an incident

was “beyond the control of the worker,” then it was classified

as a mechanical/technical failure. If the incident was not a

mechanical/technical failure, then the team had to make an

expert judgment about whether or not the worker “recognized the hazard.” This conclusion was based on the nature

of the hazard, the victim's background, and experience as

reported in the narrative. Finally, if it was determined that the

victim was experienced enough to recognize the hazard, then

it became an issue of the worker making a decision to engage

in a specific behavior that eventually led to an incident.

The second principal category, Activity, refers to the work

activity of the victim at the time of the incident — routine

maintenance, troubleshooting, repair, or normal job. Because

the narrative data is often sketchy, two additional elements

were added — “Unknown/Undetermined” and “Other.”

Other variables taken from the MSHA accident reports

were: amount of time into shift when the incident occurred;

body parts injured; total mining experience; and job

experience when the arc flash incident occurred.

Data for total mining experience and job experience were

collapsed. For these variables, the data were recoded into

experience levels of less than 2 years; 2 but less than 5 years;

5 but less than 10 years; and 10 years or greater. Researchers

were also interested in how much time had elapsed into the

worker's shift before the incident occurred. “Time at work”

data were collapsed into the categories of less than 2 hours;

2 but less than 4 hours; 4 but less than 6 hours; and 6 hours

or more.

3.2. Phase Two

3.2.1. Interviews

In the second phase of the study, a self-reporting

measurement technique was used to collect information

from persons who were either victims of or witnesses to an

electric arc flash event. This was a natural extension of Phase

One, as researchers sought additional, more in-depth

behavioral data. It was decided that personal interviews of

such individuals could provide valuable insight into both

individual and organizational behaviors. The MSHA National Mining Academy helped identify subjects in the

mining industry and the International Brotherhood of

Electrical workers identified workers in general industry.

Because the focus of the investigation was on the human and

organizational behavior aspects of arc flash incidents it was

not important what industry the subject's represented.

Participants were asked to give a detailed account of the

event, their work activities at the time of the incident, their job

experience and qualifications, and a retrospective evaluation of

their arc flash incident. For the latter, subjects were asked to

assess, from their perspective, causes and possible prevention.

Additionally, participants were asked to complete a six-item

survey about the safety climate in the workplace where the

arcing event occurred. Researchers adapted questions from the

general NIOSH Generic Job Stress Questionnaire Safety

Climate Survey for this study (NIOSH, Division of Behavioral

and Biomedical Sciences; DeJoy et al., 2004; Zohar, 1980).

The focus of each interview was on the person's

description of various behavioral aspects of the event, not

on its technical features. Thirty of the interviews were

conducted in person; two were completed by phone.

3.2.2. Subjects

The sample consisted of 32 persons; 27 were arc flash

victims and 5 were witnesses to an arcing event. Eighteen of

the subjects were working in the mining industry when the

incident occurred and 14 were employed in general industry.

Fifteen of the 18 mining industry workers were employed at

underground mines, and 3 were working at surface

operations. The final sample size was determined by the

“saturation” of responses. That is, when researchers hear the

same information from subjects again and again, saturation

in data gathering has been achieved.

The number of subjects interviewed at that point would

represent the complete sample (Glaser & Strauss, 1967). The

present study reached saturation after interviewing 32

persons.

Assistance in locating subjects was provided by State and

Federal (MSHA) mine district personnel, independent mine

trainers, and the International Brotherhood of Electrical

Workers (IBEW). Subject participation was voluntary and

anonymous.

3.2.3. Focused Interview Guide

The data collection instrument used in this study was an

interview guide (Appendix A). Four separate interview

guides were developed. Each focused on a different group of

subjects. The four groups and the number of persons in each

group included the following: victim of an arc incident

working in the mining industry (13); witness to an arc

K. Kowalski-Trakofler, E. Barrett / Journal of Safety Research 38 (2007) 597–608 601
incident working in the mining industry (5); victim of an arc

incident working in general industry (13); and witness to an

arc incident working in general industry (1).

The interview guide consisted of both open-ended and

closed-ended (yes or no) questions. An “other” category was

added to allow subjects to respond in any way they liked. In

effect, this allowed researchers to further explore the

respondents' thoughts. The questions covered demographics

of participants, incident details, victim/witness perceptions

about the incident, and organizational safety culture. Two

researchers and the interviewee met in a quiet setting at the

person's workplace. Notes were taken by the researchers

during the interviews, and all information was coordinated,

coded, and incorporated into a Microsoft Excel file for

reduction and evaluation.

Participants were asked not to identify themselves or their

company in writing by name. Thus, the information was

totally anonymous and subjects were assured of confidentiality. The amount of time extended per interview ranged

from approximately one hour to well over two hours. Net

interview time depended upon the respondent's motivation

and interest in contributing to the discussion.

To assess the safety of the work culture at the time of the

incident, questions from the NIOSH generic safety climate

survey were adapted and completed by each subject.

Responses to the six questions (Appendix A) were asked

using a rating scale of 1 to 4. One is associated with a less

safe or more negative safety culture, and 4 represents a safer

or more positive safety culture.

3.2.4. Limitations of the study

This is a descriptive study utilizing a causal–comparative

method and, as such, can only be used to explore causal

relationships, not confirm them. The sample is a nonprobability one called a haphazard sample of convenience.

Since the selection of collaborators was indiscriminate and

arbitrary, it is obviously not a representative sample, and

results cannot be generalized. Nevertheless, participants did

enable researchers to achieve their objective, as they

supplied first-hand information of actual arcing incidents

and, thus, provided documented insight from which

particular aspects of their behavior before, during, and

after the arc event could be identified. This study, as in all

self-report studies, is limited by the subject's recall. In

addition, the limitations of the MSHA narrative data must be

noted as discussed earlier.

4. Results

4.1. Phase One

Analyses were performed using the evaluative criteria

described in the Method of Study section. In the first element

of the Organization of Work category, Mechanical/Technical,

a total of 284 of the 836 incidents (∼34%) resulted from

electrical component failure. It was determined that these

cases had no organizational or behavioral component, so

they were eliminated, and the remaining 552 cases were used

for the analysis.

Under the second element, Hazard Recognition, in the

category Organization of Work, subjects did not recognize the

hazard in 45% (251 of 552) of the cases. In 55% of the cases,

workers did recognize the hazard. For example, if a qualified

electrician worked “live” when it was not necessary, it was

concluded that, based on his qualifications, training, and

experience level, he should have recognized the hazard in

performing the task and turned the power off before starting.

The third element, Judgment and Decision-making,

combined recognition of the hazard with judgment and

decision-making. For example, if a qualified electrician was

injured because the power was not turned off, and it was not

absolutely necessary to work “live,” then researchers

determined that the subject made a choice to work “live.”

In this element, subjects recognized the hazard and made a

choice to engage in a specific behavior that led to injury in

nearly 55% of the cases (301 of 552).

Looking at all 836 cases with regard to the job title

categories of laborer, technical, and supervisor, it was found

that laborers who had been in their occupation less than two

years incurred a larger proportion of incidents than technical

(more qualified) workers who had been in their jobs the same

amount of time. However, in looking at both classifications

of workers — laborers and technical — after 10 or more

years of experience, a larger proportion of incidents were

incurred by the technical workers. In other words, the more

experienced technical personnel were victims of a larger

proportion of the arc flash incidents than the laborers in the

study population. Moreover, the large majority of technical

workers in this group were qualified electricians.

With respect to the job title categories at the time of the

incident, most workers injured by arc burns were “electricians” or “mechanic/repairmen” (technical). They comprised 54% of all cases. For supervisors, the proportion of arc

flash incidents resembled those for technical personnel, with

the largest proportion of incidents occurring to supervisors

with 10 or more years in their job. With respect to work

activities for all occupations of workers, 74% of arc burn

incidents occurred to those doing maintenance/repair/

troubleshooting activities.

Electricians incurred 84% of their injuries while performing “electrical maintenance/repair” services, while

mechanics sustained more than 52% of their injuries

performing “electrical maintenance/repair” activities, usually

identified as troubleshooting. Troubleshooting was the single

most frequent work activity in which the victims were

engaged.

Approximately 20% of the accidents happened less than

two hours into the shift, almost 25% occurred in the second

two hours, and approximately 23% happened between four

and six hours into the shift. It was found that the largest

proportion of injuries, approximately 32%, occurred 6 hours

or more into the worker's shift.

602 K. Kowalski-Trakofler, E. Barrett / Journal of Safety Research 38 (2007) 597–608
Finally, for electricians in the study population, 45% of

the arc flash burn injuries occurred to the hand or fingers;

28% to the eyes; and 16% were to the wrist, arm, and

forearm. In a large majority of the incidents, injuries

occurred to multiple parts of the victim's body.

4.2. Phase Two

In the focused interview guide discussed in the Method of

Study section, six open-ended questions and a six-item

safety climate survey were posed to the subjects.

The first question related to certain demographics of the

victims/witnesses and the specific details of their arc flash

incidents. The majority of participants (∼72%) were

classified as electricians. The number of years working in

this job title ranged from 3 to 37 years, and 87% of the

sample had more than 6.5 years of experience in their job

title when they had the arc flash incident. The age of subjects

at the time of the incident ranged from 24 to 55 years old.

The average was 37 years old with 16 years electrical

experience. Nine of 10 victims were qualified to perform the

electrical tasks in which they were involved when the arc

incident occurred. In 87.5% (28 of 32) of the incidents, the

subjects had received formal electrical training and were

certified electricians. Further, almost three-fourths of the

victims had five or more years of electrical experience.

Nearly 60% of voltages in which an arcing incident

occurred were 480 volts AC. The working voltages ranged

from 440 AC to 4160 AC and from 128 DC to 560 DC. Eight

of 32 participants were involved in DC arcing incidents.

Most of these occurred with trolley systems in underground

mines. Twenty-three of the 32 subjects (78%) were

performing maintenance/repair or troubleshooting when the

arc flash incident occurred.

Subjects were asked if they were injured and which body

parts were affected. Twenty-eight of 32 said they were

injured. They reported arc burns to the hand and fingers

(41%); eyes (34%); and wrist, arm, and forearm (38%). More

than 90% of the incidents resulted in injury to multiple parts

of the body.

Next, subjects were asked to describe, in as much detail as

possible, the arc flash incident in which they were involved.

Their responses provided ample amounts of first-hand data

from which some behavioral information could be gleaned.

Here is an example of one incident description:

A qualified electrical maintenance foreman with 4 years

of electrical experience was doing troubleshooting work

on the lighting circuit on a continuous miner. He began

his investigation by pulling fuses at the 480 V to 110 V

transformer feeding the circuit. He was looking for

continuity in the lighting circuit (110 V AC) side of the

transformer. His volt-ohmmeter was set on resistance

and everything checked out. He then began to check for

power at the 480 VAC fuse holder. In a hurry to get the

continuous miner running as soon as possible, he

accidentally left his volt-ohmmeter set on resistance. As

he began to check for power on the high voltage side of

the transformer, the meter exploded and a phase to phase

arcing–fault occurred at the fuse holder. He received 3rd

degree burns on approximately one-half of his right

hand. In his own words: “I was lucky I didn't get hurt a

lot worse because I wasn't wearing safety glasses or

gloves. I was careless and worked on something that was

energized and didn't need to be because I was in a

hurry.” He indicated the incident absolutely could have

been prevented. He also said from that point on, he made

it a practice to work on any electrical problem only with

proper PPE.

Additional behavior information was provided in several

follow-up questions about their perceptions of the incident

they just described. The first question was “Do you believe

this incident could have been prevented? If yes, how could it

have been prevented?” Nearly 94% of the participants (30 of

32) stated that the incident could have been prevented. The

two leading explanations for how it could have been

prevented were appropriate use of PPE — 47% (15 of 32)

and lockout/tagout / shouldn't have worked live — 41% (13

of 32).

The next question asked the subjects to indicate what they

feel is important in preventing arc flash incidents. Responses

included don't work in such a hurry; be more careful; don't

take shortcuts; think the job through; better job preparation;

follow accepted work procedures; and don't be complacent.

Other replies to this question were better maintenance of

electrical equipment and better communication and become

aware of other workers' actions.

When asked why arc flash incidents happen and what

these incidents have in common, the leading group of

responses included the following:

• hurrying to get the job done - (16 of 32)

includes don't want to inconvenience customer and production pressure

• inadequate electrical training - (10 of 32)

includes work not done by “qualified” electrician

• complacency - (10 of 32)

includes lack of attention to task

• carelessness - (6 of 32)

• working “live”- (6 of 32)

includes failing to lockout/tagout

Other noteworthy responses to the questions of why arc

flash incidents happen and what they have in common

included not following accepted procedures; poor maintenance of equipment; not using PPE; insufficient planning to

see job through; worker out of position in work area; poor

judgment; using improper testing equipment; and lack of

communication.

Subjects were then asked what could be done to make it

less likely that workers would be exposed to arc flashes. The

K. Kowalski-Trakofler, E. Barrett / Journal of Safety Research 38 (2007) 597–608 603
leading responses were wear PPE — (10 of 32); turn power

off — (9 of 32); follow rules and policy procedures — (8 of

32); and modify design of electrical equipment — (6 of 32).

Other suggestions included training in awareness of arc

dangers; don't take chances; think the job through; and eliminate bad habits. Several of these suggestions are noted in

the following account:

A qualified electrical general inside laborer with 6 years

of electrical experience was running a 15-ton GE motor

that was hauling empty supply cars on a Saturday

maintenance shift. The pole on his motor jumped the

300 VDC line and wedged between the belt hanger and

top of an overcast. He got off the motor on the tight side

of the entry and grabbed the base of the “harp” pole

with his bare hands. The pole arced between the trolley

and the trolley hanger and injured him with flash burns

to his eyes and the taste of copper in his mouth. He also

got shocked as he became a grounded part of the circuit

and was thrown against the ribs. In his own words: “I

was in a hurry and I didn't think the job through. I had

picked up a bad habit learned from older miners.” He

said the incident absolutely could have been prevented if

he had put on his gloves and not looked at the pole. He

also said he was going too fast and that is what caused

the pole to jump in the first place.

The last part of the interview guide related to organizational behavior (i.e., the safety climate where persons

worked when they experienced an arc flash event). Subjects

rated each of six questions (refer to Appendix A, Part B) on a

scale of 1 (Strongly Disagree) to 4 (Strongly Agree), with 24

points representing the maximum score. Safety climate

responses were grouped as follows: 6 to 15 — poor; 16 to

20 — average; and 21 to 24 — good. Results showed that

∼27% of the subjects (8 of 30) reported a poor safety

climate; ∼46% (14 of 30) reported an average safety climate;

and ∼27% (8 of 30) said they had a good safety climate.

5. Summary and Discussion

The main objective in this study was to learn of the

individual and organizational behavioral factors associated

with non-contact arc flash incidents. This was accomplished

by investigating various aspects of past incidents, as detailed

in official MSHA accident reports, and by conducting

personal interviews with victims and witnesses to arc flash

events. Information was obtained in two phases: (a) by

reviewing 836 mining industry electric arc burn accident

reports, and (b) by interviewing 32 persons from mining and

general industry who had been victims in arc flash incidents.

The subjects in Phase One represent the population of

victims of arc flash incidents in the mining industry over an

11-year period; therefore, their demographic data are

statistically reliable. However, as noted earlier in the

discussion of the narratives, behavioral data were subject

to interpretation. In contrast, subjects in the second phase of

the study did not come from a statistically representative

random sample. As a result, neither the demographic nor

behavioral data collected and reported in this phase can be

used to characterize the population of workers who have

incurred an arc flash injury. In addition, the incidents

subjects reported in some cases happened 15 years previously, while other incidents happened in the past few years.

Thus recall bias must be taken into account. Regardless of

these limitations, information is reported that appears to be

meaningful to the extent that it should be given consideration

in designing interventions for preventing or reducing the

occurrence and severity of arc flash injuries.

It was observed in both phases of the study that most

victims in these arc flash incidents, regardless of the industry

in which they worked, were experienced electrical persons

who had more than 10 years on the job at the time of the

incident. This is meaningful because it opposes the historical

expectation that more job experience equals fewer accidents

and injuries. The subjects in Phase One averaged approximately 9 years of job experience; the victims in Phase Two

averaged 16 years of electrical experience. The large majority of victims in Phase One and Phase Two had also received

formal electrical training and were certified electricians.

The subject of electrician training and certification came

up in dialogue with several of the interviewees. An issue

seldom considered by organizations in hiring electricians is

the need to evaluate their electrical qualifications and

specific experience. The first question usually asked

concerns the qualifications and certifications of the electrician. This query is normally completed by the human

resources department. The second question concerns the

individual's experience. This usually is not investigated in

depth, as there is an expectation that an individual certified as

an electrician can do anything electrical. An interviewee

shared an experience with the researchers wherein his

company had hired an electrician. When a problem arose

with the battery-operated power center, the electrician

realized that he had worked at mines with electrical current

and had no idea how to work on this battery. He was

qualified, but he did not have experience in this area of

electrical work and consequently was injured. Checking

performance on specific tasks is the manner in which

proficiency is determined.

The most common job classifications of arc flash victims

at the time they were injured were electricians and mechanic/

repairman. “The most common work activity of nearly threefourths of the subjects was electrical maintenance/repair or

troubleshooting.” There is no established curriculum for

electricians in repair and troubleshooting. Companies may

provide workers troubleshooting on the company's specific

equipment, and when a new piece of equipment is purchased,

the manufacturer usually trains the workers. In Phase One, it

was found that approximately one-third of the arc flash

incidents in these work activities occurred after more than six

hours into the shift. This “time-into-shift” data suggests that

workers may have been careless, fatigued, or hurrying to get

604 K. Kowalski-Trakofler, E. Barrett / Journal of Safety Research 38 (2007) 597–608
the job done. These explanations are among the several

reasons given by Phase Two subjects for why arc flash

incidents happen.

The data suggests that one of the more important

conclusions in this study is that many workers knew of the

potential consequences of their actions, yet made a decision

to engage in risky behaviors that led to arc flash incidents.

Using the argument that victims had, on average, significant

electrical experience and job experience, it can be conjectured

that they indeed recognized the hazards of the task in which

they were working when the arc flash incident occurred but

made conscious judgments/decisions to engage in a risky

behavior that led to the event. For example, an experienced

electrician should know when to turn the power off while

performing a specific task or when to use the correct tool.

Thus, since workers with more experience were getting hurt

at higher rates, it is suggested that they were either not

recognizing the hazard (unlikely) or making a judgment/

decision (more likely) to engage in a risky behavior leading to

the accident. Experienced electrical workers who have the

knowledge and know the correct procedures are making

judgments/decisions to engage in a behavior that eventually

leads to an arc flash incident. Why? Some reasons given by

Phase Two subjects included: time pressures (that is,

hurrying to get the job done because they don't want to

inconvenience the customer), production pressures, insufficient planning to see the job through, and taking shortcuts.

For these reasons, workers tend to work “live,” not use PPE,

and, in general, not follow accepted work practices.

In Phase One incidents, it was determined that in a

substantial number of instances the worker recognized the

hazard and made a decision to proceed with behavior that led

to the incident. In practically every interview in Phase Two,

the issue of making a judgment/decision to complete an

assignment by taking a short-cut was mentioned even though

the worker knew it was wrong to do so. Comments like these

were made: I was careless and did not think through the

job... I didn't follow procedure... I let the boss's time pressure

affect my judgment on what was safe...I made a decision not

to turn the power off... I have been working in this area for

many years and have made choices to take shortcuts because

I “knew” what I was doing... I figured I could do this quick

without taking the time to put on the gloves (or glasses or

other protective gear)... I had done this a thousand times and

nothing had ever happened....

Several questions relating to the prevention of arc flash

incidents were asked of the interviewees in Phase Two.

The first one asked, in retrospect, was if the incident in which

they were involved could have been prevented. Ninety-four

percent of the subjects answered “yes.” The number one

preventative measure suggested was “turn the power off.”

The data on body parts that were injured in arc flash events

are reported in both phases of this study and indicate that

the arc flash burns affected multiple parts of the body. This

finding suggests that appropriate PPE is important for

electricians, regardless of the task they are doing.

Besides the relevance of PPE for preventing arc flash

injuries, the subjects also seemed to point to the importance

of behavioral issues. Specifically, there was a recurring

behavioral theme in responses to follow-up questions

relating to what subjects feel is important in preventing arc

flash incidents; why these incidents happen; what they have

in common; and what could be done to make it less likely

that workers would be exposed to an arc flash event. Leading

responses to such questions included: don't work in such a

hurry; be more careful and don't take chances; don't take

shortcuts; think the job through; don't be complacent; follow

accepted work procedures; use PPE; turn power off.

The safety culture of an organization is generally

recognized as an important component for insuring individual

worker safety. However, arc flash incidents appeared to occur

to subjects in Phase Two irrespective of the organization's

outlook on safety. Seventy-three percent of the incidents

reported occurred to individuals who worked for organizations

that had an average or good safety culture. It cannot be

concluded from this study that safety culture is not important,

only that with this small sample it did not seem to play a major

part in behavior. Several subjects indicated their companies

had an excellent safety culture. They also indicated that even in

the best of circumstances the unexpected can happen.

Interestingly, within the more positive safety culture,

individual decision-making represented a major part in

determining behaviors that led to the flash incident. Thus, it

may be suggested that this particular group of subjects,

working in what they judged to be a safety conscious company,

took more responsibility for their own actions. The other major

pattern in the more positive safety cultures was the pressure for

production, generally evidenced as supervisory demands.

Thus, the management's positive safety climate was not

necessarily reflected in front line supervisors, who must

balance the safety needs with production needs.

In the less positive safety cultures, workers reported

inconsistency in training and communication. In addition,

the pressure of production and supervisor demands was a

major factor in the behaviors that led to the incidents.

Deenergizing equipment before performing maintenance

and repair is clearly the best protection against the

occurrence of an arc flash. For troubleshooting activities,

however, power must usually be left on. In this case,

electrical safe work practices must be adhered to and workers

must be appropriately qualified. Focused and effective

training, not just technical but also behavioral, is perhaps

the best way to achieve this objective.

6. Recommendations

Based on conclusions from the data, the authors make the

following specific suggestions related to training:

1. Utilize the Safe Job Performance Model to guide the development of non-contact electrical arc programs to include the hierarchy of engineering controls, administrative

K. Kowalski-Trakofler, E. Barrett / Journal of Safety Research 38 (2007) 597–608 605
controls, and behavior controls. First, work at engineering the

hazard out of the workplace, then, apply administrative

controls such as policies and standard operating procedures,

and, finally, include behavior interventions, such as attitudes,

safety culture, and personal responsibility. Include knowledge and skills necessary for safe performance and integrate

judgment and decision-making skills into training

curriculum.

2. Target at-risk populations including:

a. new, inexperienced workers (those with less than three

years on the job). This population is usually targeted

with present electrical safety programs in the acquisition of skills and knowledge.

b. qualified workers (certified electricians and mechanics

with 10-16 years or more experience). MSHA designated job categories of electrician and mechanic/

repairman

c. supervisory personnel

3. Method: Use a recommended training format for adult

learners. Utilize methods proven successful for adult

learners, such as hands-on instruction, experiential

classroom learning, on-the-job-training, coaching, and

building on the worker's knowledge.

4. Content of training for electrical safety programs should

focus on technical skills, knowledge, and judgment

decision-making skills. Overall, present programs provide very good skills training and electrical knowledge

acquisition. The authors suggest that introducing a

judgment and decision-making curriculum including

awareness and hands-on problem solving situations

could impact the frequency of non-contact electrical arc

incidents. This content would include a discussion of the

reasons why qualified electricians choose unsafe behaviors, and it would include findings from this study.

Electrical safety curriculum should raise awareness of

activities performed that have been shown to be more

dangerous, specifically troubleshooting and repair activities.

Present training seems to focus on installation and

maintenance. The authors suggest that attention also needs

to be paid to the non-routine type of activities found daily on

the job, such as troubleshooting and repair. Safer techniques

to perform these activities need to be developed. In addition,

discussion of increased vigilance six hours into a shift should

be included in the curriculum.

Use appropriate personal protective equipment (PPE).

PPE can reduce injuries to the hand, fingers, eyes, wrist, arm,

and forearm. PPE can mitigate the extent and severity of arc

flash injury. One individual in the study said, “Always be

prepared to ‘gear-up.’ No matter how smart you are or how

well trained, no one can prevent the unexpected from

happening, so be prepared.”

It is judicious to acknowledge that human behavior does

affect the application of engineering and administrative controls and the success of behavioral interventions. Interventions

on the worker level should not be discouraged by supervisors

or peers. Non-contact arc flash incidents will continue to

happen. The authors want to emphasize that, in their analysis

the single, most important finding from this study is the key

role that judgment and decision-making play in the frequency

and severity of injury in these incidents. Raising awareness,

through training of worker's on-the-job judgments and

decision-making would be an important step toward reducing

these serious, debilitating, and sometimes fatal incidents. The

authors recommend further study in this area.

Acknowledgements

James Cawley, Gerald Homce, Michael Yencheck,

Charles Vaught, Michael Brnich, NIOSH; Ed Newcomb,

Max Porter, Jon Montgomery, MSHA; Dennis Eicker, Bob

Carbone, International Brotherhood of Electrical Workers;

Dr. Mary Capelli-Schellpfeffer, Capschell, Inc; Ernest

Kelley; Dave Lewetag; Paul Sullivan, DuPont Engineering;

and especially the victims and witnesses of electric arc

incidents who so graciously gave their time and knowledge

to help prevent others from having these incidents.

References

Capelli-Schellpfeffer, M. (2004). Can an MSDS Spark Electrical Safety.

Occupational Hazards, 31−36.

DeJoy, D. M., Gershon, R. M., & Schaffer, B. (2004). Safety Climate:

Assessing management and organizational influences on safety. Professional Safety, 49(7), 50−57.

Fischer, L. K. (2004). The Dangers of Arc Flash Incidents. Maintenance

Technology, 1−6.

Fotta, B., & Bockosh, G. (2000). The aging workforce: an emerging issue in

the mining industry. In G. R. Bockosh, M. Karmis, J. Langton, M. K.

McCarter, & B. Rose (Eds.), Proceedings of the 31st Annual Institute of

Mining Health, Safety and Research (pp. 33−45). Blacksburg, VA:

Virginia Polytechnic Institute and State University, Department of

Mining and Minerals Engineering.

Glaser, B. G., & Strauss, A. L. (1967). The Discovery of Grounded Theory:

Strategies for Qualitative Research. New York: Aldine de Gruyter.

Goldenhar, L. M., & Schulte, P. A. (1996). Methodological Issues for

Intervention Research in Occupational Health and Safety. American

Journal of Industrial Medicine, 29(4), 289−294.

Hall, P. M., Myers, K., & Vilcheck, W. S. (1980). Arcing Faults on Direct

Current Trolley Systems. Washington, DC: Mine Safety and Health

Administration.

Hoagland, H. (1996, December). Face Shields: When You're Face to Face

with Arcing Hazards. Electrical World, 21−22.

Hoagland, H., Shinn, B., & Reed, V. (2004). A Far Better 70E. Occupational Health and Safety, 34−41.

Hoagland, H., Shinn, B., & Reed, V. (2004). Focus on Protective Apparel: A

Far Better 70E. Occupational Health and Safety, 34, 38−41.

Jones, R. A., et al. (2000). Staged Tests Increase Awareness of Arc–Flash

Hazards in Electrical Equipment. IEEE Transactions, 36(2), 659−667.

Kowalski-Trakofler, K. M., et al. (2003). Electric Arc-Induced Injuries in the

Mining Industry: A Multi-Disciplinary Approach. NOIRS, 1−9.

Laverty, G. (2001). Measuring the Performance of Fabric Systems to Protect

Against the Thermal Effects of Electric Arcs. NT New Textiles, 1−9.

McCabe, K. (2005). IEEE P1584 Guide for Performing Arc Flash

Calculations. New York: IEEE Standards Association.

Naso, M. (2004). Short Circuiting arc flash dangers. Safety and Health, 42−47.

Zohar, D. (1980). Safety climate in industrial organizations: Theoretical and

applied implications. Journal of Applied Psychology, 65, 96−102.

606 K. Kowalski-Trakofler, E. Barrett / Journal of Safety Research 38 (2007) 597–608
Appendix A

Non-Contact, Electric Arc Burn Injuries

MV Interview Guide / 2004

The purpose of this questionnaire is to collect information from miners who have been the victim of a non-contact, electric

arcing incident.

Background

Eight hundred and thirty-six non-contact, electric arc burn incidents were reported to MSHA between 1990 and 2001. These

incidents resulted in three fatalities and more than 12,000 lost workdays (LWD). This number of lost workdays accounted for over

one-third of all LWDs due to electrical injury in the mining industry during the eleven-year period. A review of narratives for these

incidents indicated that the most dangerous types of work activities for causing arc burn injuries are electrical and machine

maintenance/repair.

This type of injury has become more common because modern mining practices require higher capacity electrical distribution

systems that have heavy, available short circuit currents and energies that can initiate and sustain electrical arcing faults. In an effort

to reduce the incidence and severity of arc burn injuries, NIOSH is developing training recommendations for the purpose of

improving hazard recognition and judgment/decision making skills of miners for recognizing and avoiding electrical hazards that

could result in arcing incidents.

(A) Non-Contact, Electric Arc-Induced Burn Injury Incidents

1. The following questions relate to you, the victim of a non-contact electric arcing incident. Please answer them as carefully as

possible. If you need more writing space, use the back of this sheet.

a. What were you doing (work activity) at the time of the incident? (check one)

Maintenance ______

Installation ______

Repair ______

Troubleshooting ______

Other: ____________ ______

b. What was your job title and years of experience in that job when the incident occurred?

Years Experience

Electrician ______

Mechanic / Repairman ______

Laborer ______

Other: ____________ ______

c. What voltage were you working with at the time of the incident? (check one)

660 V ______

661–1000 V ______

More than 1000 V ______

Other (specify) ______

d. What was your age at the time of the incident?

e. Were you a qualified electrical person when the incident occurred? Yes No

f. If yes, how did you become qualified?

1. Training (specify):

2. Experience (specify):

g. How many years had you been a qualified electrical person when the incident occurred?

h. Were you injured in the incident? Yes No

i. If yes, which body parts were injured?

j. Describe, in detail, what happened in the incident.

k. Do you believe this incident could have been prevented? Yes No

l. If yes, how could the incident have been prevented?

2. From your experience, which of the following are important in preventing arcing injuries?

K. Kowalski-Trakofler, E. Barrett / Journal of Safety Research 38 (2007) 597–608 607
Kathleen M. Kowalski-Trakofler Ph.D. is a Research Psychologist with

the National Institute for Occupational Safety and Health (NIOSH) at the

Pittsburgh Research Laboratory. Dr. Kowalski-Trakofler received her

doctorate at the University of Pittsburgh and completed her M.S. and B.S.

at the University of Wisconsin—Madison. Her research interests include

human behavior in mine emergency response.

Edward A. Barrett, M.S. is a Mining Engineer, recently retired after more

than thirty years with NIOSH. Mr. Barrett completed his graduate studies at

the University of Pittsburgh.

a. Improved PPE

What type?

b. Training

What kind?

c. Changes in work procedures or practices

Describe the changes?

d. Other factors

3. Why do you believe non-contact, electric arcing accidents happen?

4. What do most non-contact, electric arcing incidents have in common?

5. What could be done to make it less likely that miners would be exposed to electric arcing?

6. Considering the different tasks in a Mine Electrician’s job, which ones are most likely to cause the electrician to become exposed

to arcing?

Please indicate how much you agree or disagree with each of the following statements about safety behavior in the mining company

where you worked when you had the arcing incident.

Use this scale for each statement and circle your choice.

Strongly Disagree Disagree Agree Strongly Agree

1 2 34

1. New employees were told up front that they

were expected to follow good safety practices.

1234

2.There were no significant compromises or

shortcuts taken by management when

worker safety was at stake.

1234

3. Employees and management acted together to

insure the safest possible working conditions.

1234

4.Employees were warned when they did not

follow good safety practices.

1234

5. The safety of workers was a big priority with

management where I worked.

1234

6. I felt free to report safety violations to my supervisor or 1234

608 K. Kowalski-Trakofler, E. Barrett / Journal of Safety Research 38 (2007) 597–608