NIOSH In-house FACE Report 2005-01 |
July 7, 2005 |
Summary
On October 12, 2004, a 26-year-old Hispanic laborer (the victim) was
electrocuted at a materials storage yard, as he guided an auger being
lifted by a truck-mounted crane onto a truck. A 7,200 volt overhead power
line ran through the middle of the 5-acre materials storage yard. The
victim was holding on to the auger when the truck boom moved, apparently
causing the crane boom or load line to contact the power line, and the
electricity to flow through the victim’s body. Two workers employed
by another subcontractor that were assisting the victim were also shocked
and knocked to the ground by the electric current. They were not permanently
injured. The crane operator saw that the three employees had fallen to
the ground. He came down from the crane operating position and ran to
check on the men and look at the crane boom, the load line, and the power
lines. [Since the crane operator was not shocked, it is assumed that he
moved the boom away from the power lines before exiting the crane cab.]
He then ran back to the operating position, lowered the auger to the ground,
and then returned to the men. Finding that the victim had no apparent
pulse and did not appear to be breathing, the crane operator began cardiopulmonary
(CPR) resuscitation efforts. One of the workers who had been shocked ran
to a nearby building to call 911, while the other waited for Emergency
Medical Services (EMS). EMS personnel responded within approximately 20
minutes and continued CPR on the victim. The victim remained unresponsive
and was transported by ambulance to a nearby hospital, where he was pronounced
dead by an emergency room physician. The two injured workers were transported
to another hospital in the area and examined. One of them was released
that day, and the other was admitted to the hospital and released two
days later.
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Photo 1. This photograph
illustrates the truck-mounted crane that was used on the day of
the incident. [Photograph courtesy of NCOSH]. |
NIOSH investigators concluded that, to help prevent similar occurrences,
employers should:
- assign a competent persona to conduct
a jobsite survey during the planning phases of any construction project
to identify potential hazards, and to develop and implement appropriate
control measures for these hazards.
- train all crane operators and crews who may work near overhead power
lines to maintain minimum clearance from overhead power lines at all
times.
- develop, implement and enforce a comprehensive safety program, and
provide safety training in language(s) and literacy level(s) of workers,
which includes training in hazard recognition and the avoidance of unsafe
conditions.
Additionally,
- municipalities should consider requiring in their bid specifications
that all contract proposals include a written comprehensive safety program
that addresses safe operating procedures and documents worker training
for all tasks to be performed under the contract.
- The authority having jurisdiction for providing emergency medical
services should identify and address barriers to timely response to
medical emergencies.
a Competent person -- one who is capable of identifying existing
and predictable hazards in the surroundings or working conditions which
are unsanitary, hazardous, or dangerous to employees, and who has the authority
to take prompt corrective measures to eliminate them.1
Introduction
On October 12, 2004, a 26-year-old Hispanic laborer (the victim) was
electrocuted at a materials storage yard, as he guided an auger being
lifted by a crane onto a truck. Two other employees of another subcontractor
that were assisting the victim were also shocked and knocked to the ground,
but were not permanently injured. On November 3, 2004, the North Carolina
Occupational Safety and Health (NCOSH) office notified the National Institute
for Occupational Safety and Health (NIOSH), Division of Safety Research
(DSR), of the incident. On November 15, a DSR safety and occupational
health specialist met with the NCOSH compliance officer assigned to the
incident. The DSR safety and occupational health specialist accompanied
the NCOSH compliance officer to the incident site the following day, took
photographs, and interviewed a city engineer/volunteer firefighter who
had responded to the incident. The victim’s employer declined an
interview. The police report and medical examiner’s report were
reviewed. The cause of death was obtained from the medical examiner.
Employer: The victim’s employer, a jack and boring subcontractor,
had five employees and had been in business for seven years. The employer
frequently worked with another subcontractor on water utility jobs. The
municipality had contracted with both the victim’s employer and
the jack and boring contractor with whom the employer frequently worked,
to complete jack and boring operations. The employer had no written safety
and health program or documented training for any of his employees, including
the victim.
Victim: The victim was Hispanic and had traveled from Mexico to
the U.S. to work as a laborer. He had a social security number and a resident
alien card. He spoke primarily Spanish. Because the victim’s employer
declined an interview with the DSR investigator, the victim’s length
of time in the United States, his length of employment with his employer,
and previous employment experience were not obtained.
Equipment: The truck-mounted crane used at the time of the incident
was an articulating telescopic boom crane (Photo 1).
The truck crane was operated by the employer’s foreman, but was
owned by the other jack and boring subcontractor that had been contracted
for the project. The foreman (crane operator) had worked for the employer
for 7 years. His training was not documented.
Incident site: A 5-acre, flat, vacant lot owned by the city was
provided as a materials storage yard to the contractor and subcontractors
working on the water utility project. There was a 7,200 volt power line
running through the middle of the materials storage yard approximately
27 feet above ground level. The yard was used to store materials and equipment
for the water utility project such as augers, carrier pipes, and steel
pipes. This was the employer’s first fatality.
Investigation
A municipality had contracted with a general contractor to complete a
3-million dollar municipal wastewater improvement project. The victim
was employed by one of two companies, working together, that were subcontracted
to perform jack and boring operations. On the day of the incident, several
laborers, including the victim, worked all day with an equipment operator
who ran a horizontal boring machine to jack and bore under sections of
a state highway to place underground water pipes, according to contract
specifications. Horizontal boring was done because North Carolina statutes
do not allow cutting into state roads. In all other areas, the ground
was excavated and the water utility lines were laid by other subcontractors
in the open trenches using backhoes.
At approximately 2:00 p.m., the jack and boring crew finished jack and
boring operations under a section of state highway and returned to the
materials storage yard (Photo 2) to load pipe and
augers for the following day’s work. The crew manually loaded three
20-foot sections of steel pipe onto a truck trailer (Photo
3). Because the 20-foot augers (Photo 4)
were too heavy to manually move, the company’s crane operator or
a crew member had hooked a crane cable line to one of several augers lying
on the ground and the crane operator had started extending and raising
the boom to make it easier for laborers to slide the auger into the steel
pipe already on the truck trailer.
The victim was holding on to the auger when the truck-mounted crane boom
apparently moved, causing the crane boom or load line to contact the overhead
power line, and the electricity to flow through the victim’s body.
Two workers employed by another subcontractor that were assisting the
victim were also shocked and knocked to the ground by electricity. They
were not permanently injured. The crane operator saw that the three employees
had fallen to the ground. He came down from the crane operating position
and ran to check on the men and look at the crane boom, the load line,
and the power lines. [Since the crane operator was not shocked, it is
assumed that he moved the boom away from the power lines before exiting
the crane cab.] He then ran back to the operating position, lowered the
auger to the ground, and then returned to the men. Finding that the victim
had no apparent pulse and did not appear to be breathing, the crane operator
began cardiopulmonary (CPR) resuscitation efforts. One of the workers
who had been shocked ran to a nearby building to call 911, while the other
waited for Emergency Medical Services (EMS). EMS personnel responded within
approximately 20 minutes and continued CPR on the victim. The victim remained
unresponsive and was transported by ambulance to a nearby hospital, where
he was pronounced dead by an emergency room physician. The two injured
workers were transported to another hospital in the area and examined.
One of them was released that day, and the other was admitted to the hospital
and released two days later.
The city engineer responded to the incident before the EMS arrived and
observed the location of the crane boom, cable line, and power lines.
At the time of his arrival, the crane boom was 4-5 feet above the closest
power line phase. There was approximately 3-4 feet horizontal separation
between the crane cable and the closest power line conductor. The city
engineer contacted the power company and the power lines were de-energized
and not returned to operation until the victim, injured workers, and emergency
responders were out of the area. While the power lines were de-energized,
the augers and pipes were moved to another location and the city engineer
measured the distance from the earth to the power lines above. The conductors
were located approximately 27 feet above ground level. The city engineer
reported that contractors had been warned verbally about the power lines
overhead, but since the area was so large and there were areas for storage
away from the power lines, the location was suitable for equipment and
materials storage. The DSR safety and occupational health specialist noted
that the storage yard was quite large and there were large, unused spaces
well away from the power lines. Also, there was standing water noted on
the ground under the power lines.
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Photo 2. This
photo illustrates the overhead power lines located at the materials
storage yard. [Photograph courtesy of NCOSH].
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Photo 3. This photo illustrates the sections
of pipe on the truck trailer into which the steel augers were to be
inserted. [Photograph courtesy of NCOSH]. |
Photo 4. This photo illustrates the steel augers that were
being lifted with the truck crane and inserted into sections of steel
pipe located on the truck trailer. [Photograph courtesy of
NCOSH]. |
Cause of Death
The medical examiner’s office reported that the cause of death
was electrocution.
Recommendations/Discussion
Recommendation #1: Employers should conduct a jobsite survey during
the planning phases of any construction project to identify potential
hazards, and to develop and implement appropriate control measures for
these hazards.
Discussion: Before beginning work at any construction site, a competent
person should evaluate the site to identify any potential hazards and
ensure appropriate control measures are implemented. At the materials
storage yard, a 3-phase 7,200 volt overhead power line was located directly
above the area where steel augers and steel pipe had been stored. Materials
and equipment should be stored a safe distance away from all power lines,
if possible.
In situations where there is a potential electrical hazard but work cannot
be relocated, employers should work with the utility company to minimize
or eliminate the hazard.2, 3
All workers on site should be made aware of hazards present and the control
measures that are to be followed to avoid them.
Recommendation #2: Employers should train all crane operators and crews
who may work near overhead power lines to maintain minimum clearance from
overhead power lines at all times.
Discussion: Occupational Safety and Health Administration (OSHA) standards
for the Construction Industry have specific requirements for using cranes
and derricks located in Subpart N.4 29
CFR 1926.550(a)(15) requires that “except where electrical distribution
and transmission lines have been de energized and visibly grounded at
point of work or where insulating barriers, not a part of or an attachment
to the equipment or machinery, have been erected to prevent physical contact
with the lines, equipment or machines shall be operated proximate to power
lines only in accordance with the following: (i) for lines rated 50 kV.
or below, minimum clearance between the lines and any part of the crane
or load shall be 10 feet.”
Also under general requirements for cranes and derricks located in 29
CFR 1926.550(a)(15)(iv), OSHA requires that “A person shall be designated
to observe clearance of the equipment and give timely warning for all
operations where it is difficult for the operator to maintain the desired
clearance by visual means.” OSHA standard 29 CFR 1926.550(a)(4)
requires that “Hand signals to crane and derrick operators shall
be those prescribed by the applicable [not part of quote: added by author:
American National Standards Institute] (ANSI) standard for the type of
crane in use. An illustration of the signals shall be posted at the job
site.” Hand signals in accordance with ANSI B30.55
were prescribed for the type of crane in use, but no worker had been designated
to guide the crane operator and the hand signals were not posted at the
site on the day of the incident. All employers should comply with and
reinforce these safety requirements through safety training and during
safety meetings. Training should always include procedures that crane
operators are to follow in the event of contact between a crane and an
energized line. The Construction Safety Association of Ontario, Canada
(CSA) recommends that the following safety procedures be followed:
- The crane operator should remain inside the cab.
- All other personnel should keep away from the
crane, ropes, and load, since the ground around the machine might be
energized.
- The crane operator should try to remove the crane
from contact by moving it in the reverse direction from that which caused
contact.
- If the crane cannot be moved away from contact,
the operator should remain inside the cab until the lines have been
de-energized.6
In this instance, since the crane operator was not shocked, he most likely
reversed the boom sufficiently to move it away from contact with the lines,
got off the crane to evaluate the situation, and then reentered the crane
cab to lower the load to the ground.
Information useful for training workers about hazards involved with crane
operations near overhead power lines can be found in the NIOSH Alert:
Preventing electrocutions of crane operators and crew members working
near overhead power lines.2 In addition,
Worker Deaths by Electrocution, A Summary of NIOSH Surveillance and
Investigative Findings3 provides additional
information for worker training. Both documents are available through
the NIOSH web site at http://www.cdc.gov/niosh/injury/traumaelec.html
or by calling 1-800-356-4674. The NIOSH Alert has a worker/employer summary
sheet that can be posted at the work site or given to workers and may
serve as an additional means to communicate safe work practices to workers.
If employers have implemented additional controls for the crane, such
as installing proximity warning alarms and or insulated links, training
should emphasize that these are supplemental and are not a substitute
for maintaining minimum clearances.
Current federal laws do not require crane operators to be licensed or
certified. At present, 12 states (California, Connecticut, Hawaii, Massachusetts,
Montana, Nevada, New Jersey, New Mexico, New York, Oregon, Rhode Island,
West Virginia) and 6 cities (Chicago, Los Angeles, New York, New Orleans,
Omaha, Washington DC) require crane operators to be licensed. Certification
is usually a voluntary process initiated by a non-governmental agency
through which individuals are recognized for their knowledge and skill.7
Licensure is more restrictive and usually refers to mandatory governmental
requirements based upon some combination of examination, testing, and
demonstration of the appropriate skills, knowledge and experience. A negotiated
rulemaking committee for OSHA has drafted revised regulations for crane
and derrick safety that would require crane operator testing and certification.8
To exercise good safety practice, employers should consider implementing
an operator testing and certification program regardless of this proposed
rule change.
Recommendation #3: Employers should develop, implement and enforce a comprehensive
safety program, and provide safety training in language(s) and literacy
level(s) of workers, which includes training in hazard recognition and
the avoidance of unsafe conditions.
Discussion: Employers should evaluate tasks performed by workers, identify
all potential hazards, and then develop, implement, and enforce a safety
program that meets applicable OSHA standards addressing these identified
hazards. The safety program should include, at a minimum, worker training
in hazard identification, and the avoidance and abatement of these hazards.9
Companies that employ workers who do not understand English should identify
the languages spoken by their employees and design, implement, and enforce
a multi-language safety program. To the extent feasible, the safety program
should be developed at a literacy level that corresponds with the literacy
level of the company’s workforce. Companies may need to consider
providing special safety training for workers with low literacy to meet
their safety responsibilities. The program, in addition to being multi-language,
should include a competent interpreter to explain worker rights to protection
in the workplace, safe work practices workers are expected to adhere to,
specific safety protection for all tasks performed, ways to identify and
avoid hazards, and who they should contact when safety and health issues
arise.
Recently OSHA developed The Hispanic Outreach Module to assist
employers with a Spanish-speaking workforce in learning more about workplace
rights and responsibilities, identifying Spanish-language outreach and
training resources, and learning how to work cooperatively with OSHA.
In addition, the module provides a list of OSHA’s Hispanic/English-as-a-second-
language coordinators. These materials are available at http://www.osha.gov/dcsp/compliance_assistance/index_hispanic.html
10 or can be obtained by contacting an
OSHA area office. Information provided can be used by employers who are
developing or improving safety and training programs for their Spanish
speaking employees.
Recommendation #4: Municipalities should consider requiring in their bid
specifications that all contract proposals include a written comprehensive
safety program that addresses safe operating procedures and documents
worker training for all tasks to be performed under the contract.
Discussion: To help foster safe work environments for contracted employees,
municipalities can require all potential contractors to submit a written
safety program as part of their bid specifications. By requiring in the
bidding process that safety programs, at minimum, meet OSHA safety and
health standards, contractors are reminded of the importance of safety
and that the costs of safety are a recognized and necessary cost of doing
business.
Recommendation #5: The authority having jurisdiction for providing emergency
medical services should identify and address barriers to timely response
to medical emergencies.
Discussion: According to the city engineer, who was also a volunteer
firefighter, the EMS ambulance arrived at the incident site approximately
20 minutes after the 911 call. The ambulance traveled from a nearby town
to the site but was unable to locate the vacant lot immediately. Ambulance
drivers should maintain contact with dispatchers and request a clarification
of the incident location when needed. Agencies responsible for providing
EMS ambulance services might consider installing global positioning systems
and/or computers equipped with mapping software in EMS ambulances to assist
drivers in locating sites. The National Fire Protection Association (NFPA)
has developed consensus standards regarding response times for career
11 and volunteer fire departments.12
Two of the objectives for career fire departments identified in NFPA 1710
refer to emergency medical response time and include: Four minutes (240
seconds) or less for the arrival of a unit with first responder or higher
level capability at an emergency medical incident, and eight minutes (480
seconds) or less for the arrival of an advanced life support unit at an
emergency medical incident, where this service is provided by the fire
department. For volunteer fire departments, NFPA 1720 recommends that
emergency medical service response times in rural areas be within 14 minutes
80 percent of the time. The incident summarized in this report occurred
in a rural area.
The authority having jurisdiction and responsibility for providing emergency
medical services, regardless of its designation as a career fire department,
volunteer fire department, or private EMS, should identify and address
barriers to timely response to medical emergencies and strive to meet
the NFPA consensus standards for response times.
References
- Code of Federal Regulations [2004]. 29 CFR 1926.32(f). General Safety
and Health Provisions. Washington, DC: U.S. Printing Office, Office
of the Federal Register.
- NIOSH [1995]. NIOSH
Alert: Request for Assistance in Preventing Electrocutions of Crane
Operators and Crew Members Working Near Overhead Power Lines.
Cincinnati, OH: U.S. Department of Health and Human Services, Public
Health Service, Centers for Disease Control and Prevention, National
Institute for Occupational Safety and Health, DHHS (NIOSH) Publication
No. 95-108.
- NIOSH [1998]. Worker
Deaths by Electrocution: A Summary of NIOSH Surveillance and Investigative
Findings. Cincinnati, OH: U.S. Department of Health and Human
Services, Public Health Service, Centers for Disease Control and Prevention,
National Institute for Occupational Safety and Health, DHHS (NIOSH)
Publication No. 98-131.
- Code of Federal Regulations [2004]. 29 CFR 1926.550. Cranes and Derricks.
Washington, DC: U.S. Printing Office, Office of the Federal Register.
- ANSI [1968]. American National Standard: Hand Signals. New York, NY:
American National Standards Institute, Inc. ANSI B30.5-1968.
- CSA (Construction Safety Association) [1982]. Mobile crane manual.
Toronto, Ontario, Canada: Construction Safety Association of Ontario.
- NCCCO [2004]. National Commission for the Certification of Crane Operators:
State Licensing Requirements. Fairfax, VA. http://www.nccco.org/licensing/index.html.
Accessed April 5, 2005.
- DOL (U.S. Department of Labor)[2004]. Consensus reached on recommendation
for OSHA cranes and derricks standard. Press release, 13 July 2004.
Washington, DC. [http://www.osha.gov/pls/oshaweb/owadisp.show_document?p_table=NEWS_
RELEASES&p_id=10938]
- Code of Federal Regulations [2004]. 29 CFR 1926.21(b)(2). Safety Training
and Education. Washington, DC: U.S. Printing Office, Office of the Federal
Register.
- OSHA [2005]. Hispanic Outreach Module. Accessed February 3, 2005 at
http://www.osha.gov/dcsp/compliance_assistance/index_hispanic.html
- NFPA [2004]. NFPA 1710: Standard for the organization and deployment
of fire suppression operations, emergency medical operations, and special
operations to the public by career fire departments. Quincy, MA: National
Fire Protection Association.
- NFPA [2004]. NFPA 1720: Standard for the organization and deployment
of fire suppression operations, emergency medical operations, and special
operations to the public by volunteer career fire departments. Quincy,
MA: National Fire Protection Association.
Investigator Information
This investigation was conducted by Doloris N. Higgins, Safety and Occupational
Health Specialist, Fatality Investigations Team, Surveillance and Field
Investigations Branch, Division of Safety Research, National Institute
for Occupational Safety and Health.
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