800.833.4558
www.soneticscorp.com
Wireless
communication
and crane safety
Keeping your crew safe,
effective, and productive in the
new regulatory environment
White Paper No. SO12-02.01
Sonetics Corporation White Paper No. SO12-02.01_final | www.soneticscorp.com | 800-833-4558
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2
Sonetics Corporation White Paper No. SO12-02.01_final | www.soneticscorp.com | 800-833-4558
CONTENTS
Executive summary .....................................................................................................................................5
Overview ....................................................................................................................................................7
A brief note on scope ..................................................................................................................................8
A nation of cranes ......................................................................................................................................9
Types of construction cranes .....................................................................................................................10
Are crane injuries a big problem? ...............................................................................................................10
Subpart CC in general: A new focus on crane safety ...................................................................................13
How are people injured in crane accidents? ............................................................................................... 14
Communication: The key to safety .............................................................................................................15
Wireless communication for crane safety .................................................................................................. 17
Hearing protection: An added benefit .........................................................................................................18
How to choose a wireless headset system ................................................................................................ 19
Safety and crane regulation: Some final thoughts .......................................................................................22
Notes ..................................................................................................................................................... 23
References ...............................................................................................................................................25
Appendix A: Wireless system requirements ............................................................................................... 27
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Apart from their obvious benefits for OSHA compliance,
wireless headset systems are a convenient and reliable
method of ensuring clear communication among work
crews when operating in construction, utility, and other
dangerous, high-noise environments.
4
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EXECUTIVE SUMMARY
O
SHA’S NEW CRANE RULES FOR CONSTRUCTION (29 CFR §1926, eff. Nov. 8, 2010) are the most sweeping
overhaul of crane safety regulations in more than 40 years. Of particular importance are new rules
governing communication between the crane operator, signal person, and spotter. These three individuals
are absolutely essential to safe crane operation, but until now have had to rely on hand signals or two-way radios
to communicate.
Although “universal” hand signals have been established, the system is complex and the visible differences
between some of the signals are subtle at best. Hand signals also require line-of-sight visibility, which is not
always feasible, particularly in darkness or inclement weather. Although two-way radios do not require line of
sight, they tie up one hand for operation and are subject to electronic interference. OSHA recognizes these
limitations by setting forth new and stringent requirements for
Basic Wireless Headset Communication System
signals conveyed electronically. These include:
Crane operator
• The device(s) used to transmit signals must be tested
on site before beginning operations to ensure that the
Local
signal transmission is effective, clear, and reliable.
Audio
• Signal transmission must be through a dedicated
Network
channel.
• The reception of signals must be by a hands-free
system.
These requirements make self-contained wireless communication
headsets a better option than two-way radios for OSHA
compliance since radios typically do not offer a dedicated
channel or completely hands-free operation. In the case of crane
Signal person
operations, wireless headsets are becoming the best practice for
ensuring clear and reliable communication among the crane operator, signal
person, and spotter. If desired, wireless headsets can be integrated easily
with existing two-way radio systems to enable remote communication.
• 1,600-foot
line-of-sight range
• Hands-free
• Dedicated channel
Dedicated spotter
Optional mobile radio interface
for communication with remote users
The basic building blocks of a wireless communication system are straightforward: two or more wireless
headsets; base station to allow communication between and among headsets; and an optional radio-transmit
interface to allow communication between the worksite and remote users over a mobile radio.
The benefits of wireless communication headsets are substantial. DECT-based wireless headset systems utilize a
digitally encoded, dedicated channel. Wireless headset systems also provide full-duplex, hands-free
communication within the local audio network. Full-duplex systems allow conversations to take place in both
directions simultaneously, similar to a telephone. This is an important safety feature for crane operations
because, unlike a walkie-talkie, it allows verbal warnings to be delivered instantly, even if someone else is talking.
Wireless headset systems can also be integrated with existing radio systems to enable monitoring of multiple
radios and push-to-talk transmit capabilities. Wireless headsets offer the additional advantage of hearing
protection, typically 24dB or more of noise reduction, a major concern in virtually all crane environments.
Apart from their obvious benefits for OSHA compliance, wireless headset systems are a convenient and reliable
method of ensuring clear communication among work crews when operating in construction, utility, and other
dangerous, high-noise environments. Clear communication is an essential element in every team’s effectiveness
and productivity. For crews who must work around cranes, it could even save a life.
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5
Wireless communication is a cost-effective method
of keeping your entire work crew safe, effective,
and productive — especially if they are working
with or around cranes.
6
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800.833.4558
www.soneticscorp.com
Wireless communication
and crane safety
Keeping your crew safe, effective, and
productive in the new regulatory
environment
Overview
On November 8, 2010, the Occupational Safety and Health
Administration’s (“OSHA”) new crane and derrick rules (“Rules”) for
construction took effect.1 Weighing in at over 275,000 words, the Rules
represent the first major regulatory overhaul of crane operations since
OSHA’s initial regulations were enacted in 1971. Considered by many in
the construction industry to be long overdue,2 the Rules also have some
serious teeth. No longer are words like “should” or “shall” used in the
text; indeed, the word “must” is used over 800 times.
In this white paper, Sonetics Corporation examines several key
components of the Rules, particularly with respect to communication
among the crane operator, signal person, and spotter. Sonetics proposes a
*Sonetics Corporation of Portland,
Oregon designs and manufactures
proven communication solutions for
work teams in construction, public
works, aviation, firefighting, marine,
construction, and industrial operations.
Twice named by Inc. magazine as one of
America’s 500 fastest-growing private
companies, Sonetics, together with its
Firecom and Flightcom divisions, helps
more than 500,000 customers in 90
countries hear and be heard under
challenging circumstances.
wireless voice communication solution that greatly enhances the safety,
effectiveness, and productivity of crane operations, while simultaneously
complying with OSHA’s two important new requirements for electronic
signaling: hands-free communication and the need for a dedicated
transmission channel.
The crane operator, signal person, and spotter are absolutely essential to
safe crane operation, but until now have had to rely on hand signals or
Sonetics Corporation White Paper No. SO12-02.01_final | www.soneticscorp.com | 800-833-4558
7
two-way radios to communicate. Although “universal” hand signals exist,
the system is complex and the differences between some of the signals
are subtle. Hand signals also require line-of-sight visibility. While two-way
radios do not require line of sight, they tie up one hand for operation and
are subject to interference. OSHA recognizes these limitations by setting
forth new requirements for signals conveyed electronically:
• The device(s) used to transmit signals must be tested on site before
beginning operations.
• Signal transmission must be through a dedicated channel.
• The reception of signals must be by a hands-free system.
These requirements make self-contained wireless communication
headsets a far better option than two-way radios for OSHA compliance
since radios offer neither a dedicated channel nor hands-free operation.
It is estimated that
DECT-based wireless headset systems use a digitally encoded, dedicated
more than 300,000
channel. Wireless headset systems also provide full-duplex, hands-free
cranes are in use
worldwide, and half of
those are used in
construction
communication within the local audio network. Full-duplex systems allow
conversations to take place in both directions simultaneously. This is an
important safety feature for crane operations because, unlike a walkietalkie, it allows verbal warnings to be delivered instantly, even if someone
else is talking. Wireless headset systems can also be integrated with
existing radio systems to enable communication with remote locations.
Wireless headsets offer the additional advantage of hearing protection, a
concern in virtually all crane environments.
A brief note on scope*
The Rules discussed in this white paper apply to cranes and derricks used
*This article is for informational
purposes only and not for the purpose of
providing legal advice. While information
in this article has been gathered from
sources believed to be reliable, Sonetics
Corporation does not guarantee the
accuracy or currency of this information.
If you have questions regarding
regulatory compliance, you should
consult your own attorney for advice
regarding your specific situation.
8
in “construction,” which OSHA defines as “work for construction,
alteration, and/or repair, including painting and decorating.”3 In addition to
construction, cranes are addressed in a separate set of regulations for
“general industry,” such as marine and overhead cranes. Typically, OSHA’s
construction regulations are stricter than general industry regulations,4
and employers may be covered by one or both sets of standards,
depending on the type of work being done.
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A precise definition of what constitutes “construction” vs. “general
Crane selection is one
5
industry” has been the subject of much regulatory activity. It is not
necessary for an employer to be a “construction company” in order to be
of the most important
classified as doing “construction work.”6 OSHA has also stated that
decisions a contractor
construction work is not limited to new construction; it includes the repair
makes, and the choice
of existing facilities, as well as the replacement of structures.7
of cranes often
Even if your company is not typically subject to OSHA’s construction rules,
influences the selection
there are still two compelling reasons to employ a wireless communication
system in your crane operations. First, a single construction-related
of other equipment
activity — even one incidental to your main purpose — could trigger
compliance requirements under the more stringent construction rules.
Second, wireless communication is a cost-effective method of keeping
your entire work crew safe, effective, and productive, regardless of the
type of work they may be doing. Compared to the costs of injuries and lost
work days, wireless communication systems provide an excellent return on
investment and can easily pay for themselves in a matter of weeks.
A nation of cranes
Gaze across the skyline of any city and the chances are you will see at
least one crane. It is estimated that more than 300,000 cranes are in use
worldwide, and half of those are used in construction.8 Besides being the
most conspicuous feature of a work site, cranes have become a mainstay
of the construction industry itself, due in part to the increased
mechanization of construction techniques.9 In the past, structural
elements — such as walls, flooring, and roofs — were often built on the
construction site out of raw materials. In modern construction, structural
elements are usually fabricated elsewhere and delivered to the work site
for installation, often with the aid of a crane. As a result, today’s building
contractors tend to be less concerned with equipment for production, and
focused more on equipment for materials handling. Several observers
have also noted that crane selection is one of the most important
decisions a contractor makes, and the choice of cranes often influences
the selection of other equipment.10
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9
OSHA’s own cost-
Types of construction cranes
benefit analysis
Construction cranes are of two types: tower cranes and mobile cranes.
shows that the new
crane rules will
Tower cranes are fixed to the ground on a concrete slab, rise hundreds of
feet into the air, and can reach out equally as far. The mast consists of
large triangulated lattice sections that can be bolted into place atop one
another, allowing the crane to “grow” in height along with the structure it is
affect over 267,000
helping to build. Tower cranes can be used to lift steel, concrete, large
businesses and
items like cement mixers, and other equipment. They can typically lift up to
20 tons, grow to an unsupported height of 265 feet, and extend a reach
more than 4.7
up to 230 feet, although these maximums can vary greatly in actual
million employees
practice.11 Mobile cranes are self-propelled machines that can move freely
nationwide
around a construction site. Mobile cranes vary greatly in size, from models
that fit in the back of a small truck to gigantic machines capable of lifting
1000 tons or more. Mobile cranes are used to set up tower cranes at the
beginning of a job and dismantle them when the job is finished.12
OSHA intended the new Rules to apply to a wide range of cranes. Cranes
are defined as “power-operated equipment, when used in construction,
that can hoist, lower, and horizontally move a suspended load.”13 For
purposes of illustrating the types of machinery to which the Rules apply,
the definition goes on to specify a non-exhaustive list of 17 types of
cranes.14 Excluded items include things like power shovels, excavators,
wheel loaders, backhoes, dedicated drilling rigs, automobile wreckers,
forklifts, tow trucks, and tree trimming equipment.
OSHA’s own cost-benefit analysis shows that the Rules will affect over
267,000 businesses and more than 4.7 million employees nationwide.15
Remember that those figures are just for construction activities. OSHA’s
general industry crane regulations, although less stringent, are applicable
to virtually every business.
Are crane injuries a big problem?
Crane operation is a dangerous business. Tons of material is suspended
in mid-air, personnel are working in close proximity on the ground,
10
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overhead hazards such as power lines are frequently present, the crane
operator is often unable to see exactly where the load is traveling, and
even a slight error in rigging or load calculation can cause the entire
assembly to buckle. Moreover, because cranes are such a highly visible
component of many operations, they are likely to draw extensive and
unflattering media attention when accidents do occur. Several recent
events in the Puget Sound region of Washington state illustrate this point.
On February 16, 2012, a 40-ton crane at a Seattle shipyard collapsed into
the water with the operator still inside it. Rescuers were able to pull the
man from the water and get him to the hospital, where he was treated for
serious injuries. The aftermath of the incident, with the top of the crane
protruding from the waters of Elliott Bay, was captured on video by local
news helicopters and quickly made the evening news across the Pacific
Northwest.16 Barely a week later, on February 23, the Seattle Fire
Because cranes are such
Department responded to an incident aboard a construction barge, where
a highly visible
a female in her late 30s had suffered a head injury after being hit by a
crane. The patient was transferred to the hospital with life-threatening
component of many
injuries.17 Two months’ prior to these incidents, a crane was badly
operations, when
damaged during the demolition of the roof at the University of
accidents do occur, they
Washington’s Husky Stadium. Although no one was injured, the crane
suffered so much damage it had to be removed. Unfortunately for the
are likely to draw
crane operator, the incident was caught on video and posted to YouTube,18
extensive and
resulting in an investigation by the Washington State Department of Labor
and Industries.19 For Seattle residents, all of these incidents punctuated
the memory of a horrifying accident in 2006, in which a 210-foot
unflattering media
attention
construction crane collapsed on Seattle’s east side, killing a 31-year-old
Microsoft employee in his apartment, injuring several others, and causing
severe structural damage to three high-rise buildings.20
Reliable statistics on crane accidents are difficult to obtain, primarily due
to underreporting.21 OSHA estimates 84 persons are killed in construction
crane accidents each year, but there is evidence that this figure is
artificially low.22 Data on crane fatalities from the Bureau of Labor
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Figure 1
Fatalities reported at craneaccidents.com: 2000-2009
400
350
300
250
200
150
100
50
0
1
2000
201
3
02
4
03
5
04
6
05
7
06
8
07
9
08
10
09
Craneaccidents.com
Crane-related fatalities
Statistics (BLS) show a high of 113 fatal accidents in 1992 to a low of 36
in 2010 (mean= 74), but there are problems with BLS data as well.
are substantial,
Recent studies have documented significant injury undercounts in
representing more
comparisons of BLS reports, state workers’ compensation data, and
OSHA injury logs.23
than 8 percent of all
construction fatalities
investigated by OSHA,
and most, if not all are
preventable
A third source of accident data is available from www.craneaccidents.com,
a privately run Web site that specializes in photos of crane mishaps.
Craneaccidents.com offers its own statistics, based on reports submitted
by Web site visitors. As shown in Figure 1, craneaccidents.com reports
significantly higher accident numbers than either OSHA or BLS, ranging
from a low of 74 deaths in 2000 to a high of 347 deaths in 2006. This
results in a mean accident rate of 162 per year, approximately twice as
high as that reported by OSHA and BLS.24
While annual statistics may vary, it is clear that hundreds of people have
lost their lives and many more have been seriously injured in crane
accidents over the past few years. In fact, a Google search for “crane
accident lawyers” yields more than 100,000 results for law firms that
specialize in this type of injury. It is also worth noting that none of the
preceding data sources report “near misses.” If these were included, the
picture of crane safety would undoubtedly look even grimmer. As the
authors of one study succinctly observed, “Crane-related fatalities are
substantial, representing more than 8 percent of all construction fatalities
investigated by OSHA, and most, if not all are preventable.”25
12
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Subpart CC in general: A new focus on crane safety
In promulgating the new Rules, OSHA attempted to address several critical
components of crane safety. A discussion of all the changes is beyond the
scope of this paper; however, the major impacts are as follows:26
•
Federal requirements for the training and certification of crane
operators, and requirements for third-party crane operator certifiers.
Employers must train their crane operators and signal persons in
accordance with a new national standard for certification. Prior to this
requirement, there was no national standard for crane operations
training, although 15 states and six cities had their own licensing
requirements.27
•
New requirements for communication between the crane operator,
The requirement of hands-
signal person, and spotter. Because OSHA recognizes that two-way
free communication over
radios require a free hand to operate and are subject to interference,
a dedicated channel
the Rules set forth new and stringent requirements for signals
conveyed electronically. These include:
makes self-contained
•
wireless headsets a far
The device(s) used to transmit signals must be tested on site
before beginning operations.
•
Signal transmission must be through a dedicated channel.
better option than two-way
•
Signals must be received through a hands-free system.
radios for OSHA
These unique requirements make self-contained wireless
communication headsets a far better option than two-way radios for
OSHA compliance since radios offer neither a dedicated channel nor
hands-free operation.
•
Increased crane inspection requirements. Crane inspections are
compliance since radios
offer neither of those
features
required prior to each shift, as well as ongoing monthly and
comprehensive annual inspections. Records must be kept of monthly
and annual inspections.
•
Requirements for working near electricity. Employers are required to
ensure that cranes maintain a safe distance (typically no less than 20
feet) from a power line. A dedicated spotter is usually employed to
observe the clearance and the spotter must maintain continuous
contact with the operator.
•
New rules for assembling and disassembling cranes. Employers must
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13
ensure that proper procedures are followed during crane assembly and
disassembly and supervised by a competent person.
•
New requirements for inspecting ground conditions prior to a lift. The
“controlling entity” must inform the crane operator of known ground
conditions and underground hazards that might affect safe crane
operation, such as voids, tanks, utilities, and the like. A “controlling
entity” is a prime contractor, general contractor, construction manager,
or any other legal entity that has the overall responsibility for project
construction. “Known” hazards include those identified in documents
such as site drawings, as-built drawings, and soil analyses. Acceptable
“ground conditions” mean ground that is firm, drained, and graded to
the manufacturer’s specifications for support and leveling.
•
Qualifications for riggers and signal persons. A qualified signal
person must be used when the operator’s view is obstructed or if, in
It is readily apparent that
the operator’s judgment, a signal person is necessary for safe
operation..
many incidents could
Employers who operate cranes on a construction site are responsible for
have been prevented with
complying with all aspects of the standard, but other on-site employers
better communication
have responsibilities as well. OSHA’s multi-employer policy imposes
compliance duties on employers who create or control hazards, expose
and the ability to warn
their employees to hazards, or have general supervisory authority over a
the crane operator in real
work site. Thus, even if an employer is not operating a crane itself, that
time
employer is still responsible for protecting its employees against
reasonably foreseeable hazards if they are working around cranes.
How are people injured in crane accidents?
OSHA’s regulatory initiatives are designed to address the major causes of
crane accidents, which, as shown in Table 1, can arise from a variety of
factors. Beavers et al. examined crane accidents reported in OSHA’s
Integrated Management Information System (IMIS) for the period 19972003 and determined that struck-by-load and electrocution were the
leading causes of crane fatalities.28 Other frequent causes include
crushed-by incidents, boom failure, crane tip-over, struck by cab or
counterweight, and falls. Other researchers have reached similar
14
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conclusions, although the ordering
of factors varies slightly from study
Table 1
Contributing factors and communication failures related to crane fatalities
Proximal cause
to study.29
Contributing factors
Events
Struck by load (not boom failure)
40
Rigging failure
24
Unbalanced load
In reviewing the “contributing
Load dropped
factors” in Table 1, it is readily
Equipment damage
3
10
Accelerated movement
apparent that many accidents could
Electrocution
1
5
34
Failure to maintain required clearance
34
have been prevented with better
Boom contact
15
Cable contact
12
communication. In particular,
Headache ball/sling contact
Jib contact
factors such as improper clearance
with power lines, potential for
Load contact
Crushed during assembly/disassembly
1
15
Improper assembly
striking other objects, and
unbalanced loads could easily be
5
1
3
Improper disassembly – pin removal
10
Improper boom support
6
15
Failure of boom/cable
Boom buckling
2
Boom collapse
5
than to a crane operator. In these,
Overload
6
Equipment damage
5
and probably many other cases,
Incorrect assembly
3
more evident to a signal person
tragedy could have been avoided if
the signal person and crane
Cable snap
3
Two blocking
1
Crane tip-over
14
Overload
5
operator had been able to
Loss of center-of-gravity control
3
Outrigger failure
2
communicate clearly and verbally
High winds
2
Side pull
1
Improper maintenance
1
warn each other in real time.
Indeed, the professional literature
in occupational safety is replete
Struck by cab/counterweight
communication adversely affects
construction work sites.
3
Bridge crane in motion
1
Missing hand rails
1
Improper operation
1
Improper maintenance
1
Falls
with examples of how poor
30
4
Intentional turntable turning
3
Source: Beavers, et al. (2004)
Renowned safety specialist Gordon
Dupont, whose famed “Dirty Dozen” list of human factor errors have been adopted as a model for occupational
safety in industries ranging from aircraft maintenance to medicine, states the argument in no uncertain terms.
According to Dupont, “lack of communication” is the number one cause of accidents.31
Communication: The key to safety
As previously noted, many of the new Rules are concerned with the proper training and certification of crane
operators, signal persons, and power line spotters, all of whom are required to maintain continuous contact with
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15
“Universal” hand
each other.32 During crane operations, the ability to transmit signals
between the operator and ground personnel must be maintained. If that
signals are complex and
ability is interrupted, the operator must stop operations until signal
the visible differences
transmission is reestablished and a proper signal is given.33
between some signals
are subtle at best
Under the new Rules, three or more people could be simultaneously
involved in crane operation:
•
the crane operator;
•
the signal person; and
•
a dedicated spotter, whose sole responsibility is to make certain the
crane maintains the required clearance from power lines.
Dedicated spotters receive the same training as signal persons. This
ensures that the spotter is knowledgeable about crane dynamics and is
able to recognize situations in which the minimum clearance distance may
inadvertently be breached if, for example, the load is stopped quickly while
it is being moved near a power line.34
Traditionally, crane operators, signal persons, and spotters have had to
rely on hand signals or two-way radios to communicate. Both of these
“solutions” have serious drawbacks. Although the construction industry
has developed universal hand signals,35 the resulting system is still very
complex and the visible differences between some of the signals are
subtle at best. Hand signals also require line-of-sight visibility between the
crane operator and signal person, which is not always feasible, particularly
in darkness, inclement weather, or in the operation of tower cranes where
great distances may separate the crane operator and signal person. Twoway radios do not require line of sight, but they tie up one hand for
operation and are subject to electronic interference.36
Recognizing the importance of clear communication during crane
operations, the Rules place strict requirements on the methods used to
communicate among the crane operator, signal person, and spotter. Four
types of signals are allowed: hand signals, voice signals, audible signals
(other than voice), and so-called “new” signals.37
16
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Figure 2
Basic Wireless Headset Communication System
Wireless communication for crane safety
Because OSHA recognizes that two-way radios require a free hand
Crane operator
to operate and are subject to interference, the Rules set forth new
Local
Audio
Network
and stringent requirements for signals conveyed electronically.
These include:
•
The device(s) used to transmit signals must be tested on site
before beginning operations to ensure that the signal
• 1,600-foot
line-of-sight range
• Hands-free
• Dedicated channel
transmission is effective, clear, and reliable.
•
Signal transmission must be through a dedicated channel.
•
The operator’s reception of signals must be by a hands-free
Dedicated spotter
Signal person
system.38
Recent advances in technology have made self-contained wireless
communication headsets a far more attractive option than two-way
Optional mobile radio interface
for communication with remote users
radios.39 In the case of crane operations, they are rapidly becoming the
best practice for ensuring clear and reliable communication among the
Self-contained wireless
crane operator, signal person, and spotter. Although an infinite variety of
communication
configurations are possible, the basic building blocks of a wireless
communication system are fairly straightforward, as shown in Figure 2:
headsets are rapidly
•
Two or more wireless headsets
becoming the best
•
Base station to allow communication between and among headsets
•
Optional radio-transmit interface to allow communication between the
practice for ensuring
worksite and remote users over a mobile radio.
clear and reliable
The benefits of wireless communication headsets over two-way radios are
substantial. Wireless headset systems, particularly those equipped with
Digital Enhanced Cordless Telecommunications (DECT) technology, utilize
a digitally encoded, dedicated channel. Pairing the headsets to a base
station creates a closed-loop audio network, eliminating the possibility of
communication among
the crane operator,
signal person, and
spotter
other devices “breaking in” or interfering with the conversation. Although
some inexpensive, consumer-grade systems utilize Bluetooth, DECT is far
preferable for crane operations because it has nearly 30 times the range
and is far less subject to interference than Bluetooth. DECT transmissions
also have multi-pathing capability, meaning that the signal will bounce up,
over, and around obstructions to establish the best possible connection.
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17
In addition to
Properly configured, wireless headset systems also provide full-duplex,
complying with
hands-free communication within the local audio network. Full-duplex
OSHA’s requirements
for electronic signals,
systems allow conversations to take place in both directions
simultaneously, similar to a telephone. This is an important safety feature
for crane operations because, unlike a walkie-talkie, it allows verbal
warnings to be delivered instantly, even if someone else is talking.
wireless headsets
Although many of these systems include a push-to-talk button on the
can also offer a
headsets, the latter is used only to break away from the local audio
network and communicate with remote users over an optional mobile
significant amount of
radio interface. All communications within the crane crew itself are
hearing protection,
seamless, continuous, and hands-free – just like normal conversation.
an important
Hearing protection: An added benefit
consideration for all
In addition to complying with OSHA’s requirements for electronic signals,
construction sites
wireless headsets can also offer a significant amount of hearing
and most crane
deployments
protection, an important consideration for all construction sites and most
crane deployments. The National Institute for Occupational Safety and
Health estimates that approximately 30 million American workers are
exposed to hazardous levels of noise on the job. Industries with
particularly high numbers of exposed workers include: construction,
agriculture, mining, manufacturing, utilities, transportation, and the
military.40
OSHA regulations require hearing protection when the time-weighted
average noise exposure over an eight-hour period equals or exceeds 85
18
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decibels.41 “Time-weighted average” takes into account the fact that the
louder the noise, the shorter the exposure time before hearing protection
is needed. As shown in Table 2, as the decibel level increases, the
allowable exposure time without mandated hearing protection decreases.
As shown by the column of corresponding sounds, these standards are
routinely exceeded in construction environments; hence, the need for
hearing protection.
How to choose a wireless headset system
If the system you are
Wireless headset systems are available in a wide variety of configurations
considering is billed as
and price ranges. To ensure a system meets your needs, particularly when
“wireless,” it should be
purchasing a system for crane operations, consider the following factors
carefully.
•
Is the system truly wireless? A number of so-called “wireless”
truly wireless and not
require a belt pack.
systems actually require a wire from the headset to a radio or belt
pack. While these systems allow freedom of movement, the use of a
belt pack or radio wire creates many of the same problems inherent in
hardwire systems, particularly tangled cords. Moreover, belt packs
generally have less transmission range than self-contained systems
worn on the head.
•
Does the system use DECT technology? Transmission technology can
dramatically affect how well wireless systems perform in the field.
Systems that employ Bluetooth technology generally have a limited
range and are subject to interference from nearby communication
devices, especially those operating on the 2.4 GHz or 5 GHz channels.
Look for systems with the most recent version of Digital Enhanced
Cordless Telecommunications (DECT) technology. DECT 6.0 units offer
up to 30 times more coverage and are less subject to interference in
the 30MHz – 1.8GHz spectrum. DECT transmissions also have
multipath capability, meaning that the signal will bounce up, over, and
around objects in order to establish the best possible connection. For
enhanced security, DECT signals are digitally encoded to ensure
privacy in the transmission of sensitive information.
•
Is the system full-duplex or half-duplex? Half-duplex systems allow
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19
communication in both directions, but only one direction at a time,
Full-duplex or multiplex
similar to a walkie-talkie. Once a party begins transmitting, all other
capabilities are an
transmissions are essentially “locked out” until the first transmission
important safety
is over. Full-duplex systems allow communication in both directions
simultaneously, similar to a telephone. (The term “multiplexing” is
consideration because
sometimes used to describe full-duplex communication between more
they allow the parties
than two parties.) Full-duplex or multiplex capabilities are an
important safety consideration because the parties can speak and
to speak and hear
hear others at the same time, allowing verbal warnings to be delivered
others at the same
time
instantaneously.
•
Is the system radio-compatible? Wireless systems should have the
capability of interfacing with mobile radios to allow communication
with remote users. Given that there are hundreds of radio makes and
models available, look for a system with maximum interface flexibility.
•
Can the duplex capabilities be configured to your specific needs? To
maintain an orderly flow of communication and minimize the chance of
“cross-talk,” or multiple conversations taking place simultaneously,
the system should allow you to establish a hierarchy of who can talk
to whom — especially which crew members are allowed to broadcast
over the radio.
•
Is the system scalable? As your needs expand, your wireless system
should be able to expand with you. Advanced wireless systems should
be able to accommodate up to 60 users.
•
Is the system comfortable to wear and easy to use? Before buying,
physically try on a headset. It should fit snugly, but comfortably, over
the ears. If you are purchasing hard hat-compatible headsets, try one
on while actually wearing a hard hat to ensure a comfortable fit. The
controls should be readily accessible, preferably with a simple pushto-talk button or toggle-to- talk switch for accessing the radio and
allowing complete hands-free communication with the team. And if the
system is billed as wireless, it should be truly wireless and not require
a belt pack.
•
What is the system’s Ingress Protection Rating? The Ingress
Protection Rating, or IP Code, is an international standard that rates
20
Sonetics Corporation White Paper No. SO12-02.01_final | www.soneticscorp.com | 800-833-4558
the degree of protection against the intrusion of solids and liquids
Make sure the system
into an electrical unit. A wireless headset should have a minimum
is designed for use in
rating of IP65, which indicates that the unit is completely impervious
to dust and is capable of withstanding a stream of water for three
minutes without damage to the interior components.42
•
your operating
environment, ask
What is the range of the system? The greater the range, the more
effective the system will be for your application, since obstacles and
about warranty, repair,
vehicles may reduce range. Look for a minimum 1500-foot line-of-sight
and replacement
transmission capability, bearing in mind that system performance may
•
deteriorate at the outer limits of the range.
policies, and try out
What is the Noise Reduction Rating? Noise Reduction Rating (NRR)
the manufacturer’s
is the measurement, in decibels, of how well a hearing protector
reduces noise as specified by the Environmental Protection Agency.
The higher the NRR number, the greater the noise reduction. While
technical support prior
to making a decision
wearing hearing protection, your exposure to noise is equal to the
total noise level minus the NRR of the hearing protectors. For
example, if you were exposed to 95dB of noise but were wearing a
headset with an NRR of 24, your actual noise exposure would be
71dB. Look for an NRR of at least 24.
•
What is the operational temperature range? Extreme temperatures
can affect battery life and headset operation.
•
Are all components necessary for operation included in the purchase
price? The price you pay should deliver a complete system that is
ready for operation. Accessories such as battery chargers and
charging cables should be included, not “added on” as options.
•
What is the manufacturer’s track record and how knowledgeable are
its representatives? Not all wireless headset systems are equally
reliable and durable over the long term. Make sure the system is
designed for use in your operating environment, ask about warranty,
repair, and replacement policies, and try out the manufacturer’s
technical support prior to making a decision. If you purchase your
system from a dealer, he or she is a critical link in ensuring the final
solution meets your needs. Look at the dealer’s longevity and
reputation in the industry and do not hesitate to ask for references.
Sonetics Corporation White Paper No. SO12-02.01_final | www.soneticscorp.com | 800-833-4558
21
For crews who must
Reputable manufacturers choose their dealers carefully and educate
work around cranes,
them to act as “problem- solvers,” not just “order takers.” Problemsolving dealers ask lots of questions, and will attempt to thoroughly
clear communication
understand your situation before recommending a solution. Advanced
wireless headset systems offer a wide variety of configuration options
could save a life
that allow customization to your specific application. Your dealer
should be fully informed and aware of what options are available.
•
How long is the warranty? A two-year limited warranty is standard in
the industry and some vendors provide extended plans of up to five
years. In addition to length, also look at breadth of coverage.
Safety and crane regulation: Some final thoughts
Apart from their obvious benefits in terms of OSHA compliance, wireless
headset systems are a safe and convenient method of ensuring clear
communication among work crews when operating in construction, utility,
and other dangerous, high-noise environments.
In the final analysis, clear communication is an essential element in every
team’s effectiveness and productivity. If your company employs cranes its
operations, whether for construction or other purposes, Sonetics
Corporation encourages you to explore the benefits of wireless
communication headsets. For crews who must work around cranes, clear
communication could well mean the difference between life and death.
22
Sonetics Corporation White Paper No. SO12-02.01_final | www.soneticscorp.com | 800-833-4558
NOTES
1
Federal Register, August 9, 2010, pp. 47906-48177. Effective
November 8, 2010 and codified at 29 CFR §1926, Subpart CC.
with a hoisting device; sideboom cranes; straddle cranes; and tower
cranes.
2
C. O’Neill, et al., The hidden human and environmental costs of
regulatory delay. (Washington, D.C.: The Center for Progressive
Reform, 2009), pp. 13-16. See also D. Cole, “Crane safety gets a
lift: The long and winding road to update OSHA’s crane safety
regulations,” EHS Today, August 2009, pp. 240-241.
15
Department of Labor, Occupational Safety and Health
Administration, “Cranes and derricks in construction; final rule.”
Federal Register, August 9, 2010, pp. 48080-48082.
3
29 CFR §1926.32(g) and 29 CFR §1910(b)(2). These terms are
also used in section 1 of the Davis-Bacon Act (40 U.S.C. §276a) and
section 1 of the Miller Act (40 U.S.C. §270a), which OSHA notes
“have considerable precedential value” in determining what
constitutes construction work. See 29 CFR §1926.13(a).
4
Codified at 29 CFR 1910.
5
J. Stanley, “Construction vs. Maintenance,” OSHA interpretive
memorandum, August 11, 1994. www.osha.gov/pls/oshaweb/
owadisp.show_document?p_table=INTERPRETATIONS&p_id=21569
6
See New England Telephone & Telegraph Co., 4 OSHC 1838,
1939 (1976); and New England Telephone & Telegraph Co. v.
Secretary of Labor, 589 F.2d 81 (1st Cir. 1978).
7
For example, in Pacific Gas & Electric Co., 2 OSHC 1962 (1975),
the Occupational Safety and Health Review Commission held that
the replacement of a wooden utility pole is covered by the
construction industry standards. The utility had argued that the
replacement of the pole was “maintenance work,” rather than
“construction work.” The Commission, however, concluded that pole
replacement is “improvement” and, therefore, construction work.
Similarly, construction work is typically performed outdoors, rather
than at a manufacturing plant. This factor is another hallmark of
construction work. See Cleveland Electric Co. vs. OSHRC, 910 F2d
1333 (6th Cir. 1990).
8
J. Keller, “Crane safety: What you need to know when having a
crane on site and what it takes to keep your site safe,” Columbus,
OH: Presentation to the American Society of Safety Engineers, April
17, 2009.
9
A. Shapira and B. Lyachin, “Identification and analysis of factors
affecting safety on construction sites with tower cranes,” Journal of
Construction Engineering and Management, January 2009, pp. 2432.
10
A. Shapira, G. Lucko, and C. Schexnayder, “Cranes for building
construction projects,” Journal of Construction Engineering and
Management, September 2007, pp. 690-700.
11
M. Brain, “How tower cranes work,”
www.science.howstuffworks.com/transport/engines-equipment/towercrane2.htm. Accessed February 15, 2012.
12
Shapira, 2007, p. 694.
13
27 CFR § 1926.1400.
14
The list includes, without limitation: articulating cranes; cranes
on monorails; crawler cranes; dedicated pile drivers; derricks;
floating cranes and cranes on barges; industrial cranes; locomotive
cranes; mobile cranes; multi-purpose machines configured to hoist,
lower, and horizontally move a suspended load; overhead and gantry
cranes; pedestal cranes; portal cranes; service/mechanic trucks
16
www.komonews.com/news/local/Crane-collapses-into-water-atSeattle-shipyard-139468853.html
17
http://seattletimes.nwsource.com/html/localnews/
2012197549_crane25m.html
18
http://www.youtube.com/watch?v=mY7Lh0Rl81Y. A quick
search of YouTube reveals hundreds of such accidents caught on
video.
19
http://www.seattlepi.com/local/komo/article/State-investigatingcrane-incident-at-Husky-2418373.php
20
http://www.komonews.com/news/4673926.html
21
A. Shapira and M. Simcha, “Measurement and risk scales of
crane-related safety factors on construction sites,” Journal of
Construction Engineering and Management, October 2009, pp. 979989.
22
For example, a study by Suruda et al. attempted to examine the
causes of crane-related deaths for the 1984–1994 period through
an analysis of OSHA’s Integrated Management Information System
(IMIS) data. For the years in question, they found 479 accidents
involving 502 fatalities. However, the authors noted that data for
California, Michigan, and Washington State were not available for
1984–1989; the proportion of fatal accidents investigated by OSHA
was unknown; and some of the investigation reports were not
sufficiently detailed to allow the authors to determine the cause of
the accident or the type of crane involved. See A. Suruda, M. Egger,
and D. Liu, Crane–related deaths in the U.S. construction industry,
1984-94. (Silver Spring, MD: The Center to Protect Workers’ Rights,
1997); and A. Suruda, M. Egger, and D. Liu, “Fatal injuries in the
United States Construction industry involving cranes 1984–94,”
Journal of Occupational and Environmental Medicine, December
1999, pp. 1052-1058.
23
See J. Ruser, “Examining evidence on whether BLS undercounts
workplace injuries and illnesses,” Monthly Labor Review, August
2008, pp. 20-32; Workplace safety and health: Enhancing OSHA’s
records audit process could improve accuracy of worker illness and
data. GAO Report 10-10. (Washington, D.C.: Government
Accountability Office, 2009); and N. Nestoriak and B. Pierce,
“Comparing workers’ compensation claims with establishments’
responses to the SOII,” Monthly Labor Review, May 2009, pp. 57-64.
24
Craneaccidents.com draws from a global base of visitors; thus,
some of the reported accidents may have occurred outside the
United States. It may also be that craneaccidents.com receives
reports of accidents that are not reported to government regulators.
Whatever the reason, the fact that craneaccidents.com draws on
accident reports from a self-selected sample of respondents
indicates that its numbers, too, are likely to be significantly
underreported – at least on a global scale.
25
J. Beavers, J. Moore, R. Rinehart, and W. Schriver, “Cranerelated fatalities in the construction industry,” Journal of
Sonetics Corporation White Paper No. SO12-02.01_final | www.soneticscorp.com | 800-833-4558
23
NOTES
Construction Engineering and Management, September 2006, pp.
901-910.
26
See Occupational Safety and Health Administration, Small entity
compliance guide for the final rule for cranes and derricks in
construction. (Washington, D.C.: Occupational Safety and Health
Administration, 2011), pp. 7-8.
34
Ibid., p. 47948.
35
See American National Standards Institute B30.5-1968,
“Crawler, Locomotive and Truck Cranes” and American Society of
Mechanical Engineers B30.5-2007, “Mobile and Locomotive
Cranes.”
36
Federal Register (2010), p. 47997.
27
K. Hunt, Accidents highlight crane safety issues; update of
decades-old federal rule sought,” Business Insurance, June 16,
2008.
28
Ibid.
29
See G. Shepard, R. Kahler, and J. Cross, “Crane fatalities – a
taxonomic analysis,” Safety Science, February 2000, pp. 83-93; and
A. Suruda, M. Egger, and D. Liu, “Fatal injuries in the United States
Construction industry involving cranes 1984–94,” Journal of
Occupational and Environmental Medicine, December 1999, pp.
1052-1058.
30
See F. Campbell, Occupational Stress in the Construction
Industry, (Berkshire: Chartered Institute of Building, Berkshire,
2006; and R. Haslam, “Contributing factors in construction
accidents,” Applied Ergonomics, July 2005, pp. 401-415.
31
G. Dupont, “The dirty dozen errors in aviation maintenance,”
Proceedings of the Eleventh Federal Aviation Administration Meeting
on Human Factors Issues in Aircraft Maintenance and Inspection:
Human error in aviation maintenance (Washington, DC: Federal
Aviation Administration/Office of Aviation Medicine, 2007), pp. 4549.
32
Federal Register (2010), p. 47961.
33
Ibid., p. 47997.
24
37
27 CFR §1926.1419 et seq. Paragraph (d) of this section
allows “new” signals other than hand, voice, or audible signals to be
used if certain criteria are met. To ensure that any new signals
developed by a particular employer are as effective as hand, voice,
or audible signals, §§ 1926.1419(d)(1) and (d)(2) require the
employer to empirically demonstrate that the new signals are as
effective as existing signals for communicating.
38
29 CFR §1926.1420
39
R. Stager, “Wireless communication selection and use to
improve team safety,” Professional Safety: Journal of the American
Society of Safety Engineers, March 2012, pp. 60-61.
40
National Institute for Occupational Safety and Health, Workrelated hearing loss, NIOSH Publication Number 2001-103, 2001.
www.cdc.gov/niosh/docs/2001-103.
41
29 CFR §1910.95
42
Water projected by a 6.3mm nozzle, 12.5 liters per minute, at a
pressure of 30 kN/m2 from a distance of 3m.
43
HDH Group, How to avoid OSHA fines. (Pittsburgh, PA: HDH
Group, n.d.), p. 5.
Sonetics Corporation White Paper No. SO12-02.01_final | www.soneticscorp.com | 800-833-4558
REFERENCES
American National Standards Institute B30.5-1968, Crawler, Locomotive and Truck Cranes.
American Society of Mechanical Engineers B30.5-2007, Mobile and Locomotive Cranes.
Beavers, J., Moore, J., Rinehart, R., and Schriver, W. “Crane-related fatalities in the construction industry,” Journal of Construction
Engineering and Management, September 2006: 901-910.
Bello, D., et al., “OSHA issues guidance on cranes and derricks,” Safety & Health, May 2011: 16.
Brain, M. “How tower cranes work,” www.science.howstuffworks.com/transport/engines-equipment/tower-crane2.htm. Accessed February 15,
2012.
Campbell, F. Occupational Stress in the Construction Industry. Berkshire: Chartered Institute of Building, Berkshire, 2006
Cleveland Electric Co. vs. OSHRC, 910 F2d 1333 (6th Cir. 1990).
Cole, D. “Crane safety gets a lift: The long and winding road to update OSHA’s crane safety regulations,” EHS Today, August 2009: 240-241.
“Cranes: Minimize the risk,” Safety & Health, January 2011: 51-52.
Dalrymple, W. “Self help: in the world of self-erectors, operator training and certification has not been taken sufficiently seriously ... until
now.” Cranes Today, September 2003: 36-40.
Damato, R. “Pay attention to new rules for Cranes and Derricks,” Roofing Contractor, September 2010: 6
Department of Labor, Occupational Safety and Health Administration, “Cranes and derricks in construction; final rule.” Federal Register,
August 9, 2010: 48080-48082.
Dupont, G. “The dirty dozen errors in aviation maintenance,” Proceedings of the Eleventh Federal Aviation Administration Meeting on Human
Factors Issues in Aircraft Maintenance and Inspection: Human error in aviation maintenance. Washington, DC: Federal Aviation
Administration/Office of Aviation Medicine, 2007.
“Economic Analysis of Crane Rule Complete,” Professional Safety, July 2008: 17-23.
Haslam, R. “Contributing factors in construction accidents,” Applied Ergonomics, July 2005: 401-415.
HDH Group, How to avoid OSHA fines. Pittsburgh, PA: HDH Group, n.d.
Hunt, K. Accidents highlight crane safety issues; update of decades-old federal rule sought,” Business Insurance, June 16, 2008.
Keller, J. “Crane safety: What you need to know when having a crane on site and what it takes to keep your site safe,” Columbus, OH:
Presentation to the American Society of Safety Engineers, April 17, 2009.
Kime, L. “Key Elements of OSHA’s Cranes & Derricks Standard,” Occupational Health & Safety, August 2011: 34-38.
National Institute for Occupational Safety and Health, Work-related hearing loss, NIOSH Publication Number 2001-103, 2001. www.cdc.gov/
niosh/docs/2001-103.
Nestoriak, N. and Pierce, B. “Comparing workers’ compensation claims with establishments’ responses to the SOII,” Monthly Labor Review,
May 2009: 57-64.
New England Telephone & Telegraph Co. v. Secretary of Labor, 589 F.2d 81 (1st Cir. 1978).
New England Telephone & Telegraph Co., 4 OSHC 1838, 1939 (1976).
O’Neill, C., et al., The hidden human and environmental costs of regulatory delay. Washington, D.C.: The Center for Progressive Reform, 2009.
Occupational Safety and Health Administration, Small entity compliance guide for the final rule for cranes and derricks in construction.
Washington, D.C.: Occupational Safety and Health Administration, 2011.
Occupational Safety and Health Administration. Cranes and Derricks in Construction; Final Rule. Federal Register, August 9, 2010: 4790648177.
OSHA clarifies info in cranes and derricks, hazcom rules. Safety & Health, January 2012: 12-19.
Pacific Gas & Electric Co., 2 OSHC 1962 (1975).
Ruser, J. “Examining evidence on whether BLS undercounts workplace injuries and illnesses,” Monthly Labor Review, August 2008: 20-32.
Sonetics Corporation White Paper No. SO12-02.01_final | www.soneticscorp.com | 800-833-4558
25
REFERENCES
Shapira, A. and Lyachin, B. “Identification and analysis of factors affecting safety on construction sites with tower cranes,” Journal of
Construction Engineering and Management, January 2009: 24-32.
Shapira, A. and Simcha, M. “Measurement and risk scales of crane-related safety factors on construction sites,” Journal of Construction
Engineering and Management, October 2009: 979-989.
Shapira, A., Lucko, G. and Schexnayder, C. “Cranes for building construction projects,” Journal of Construction Engineering and Management,
September 2007: 690-700.
Shepard, G., Kahler, R., and Cross, J. “Crane fatalities – a taxonomic analysis,” Safety Science, February 2000: 83-93.
Snowdy, G. “Cranes & derricks in construction,” Professional Safety, February 2011: 64-65.
Stager, R. “Wireless communication selection and use to improve team safety” Professional Safety: Journal of the American Society of Safety
Engineers, March 2012, 60-61.
Stanley, J. “Construction vs. Maintenance,” OSHA interpretive memorandum, August 11, 1994. www.osha.gov/pls/oshaweb/
owadisp.show_document?p_table=INTERPRETATIONS&p_id=21569.
Suruda, A., Egger, M., and Liu, D. “Fatal injuries in the United States Construction industry involving cranes 1984–94,” Journal of
Occupational and Environmental Medicine, December 1999: 1052-1058.
Suruda, A., Egger, M., and Liu, D. Crane–related deaths in the U.S. construction industry, 1984-94. Silver Spring, MD: The Center to Protect
Workers’ Rights, 1997.
Van Hampton, T. “Enforcing the New Rule,” ENR: Engineering News-Record, May 16, 2011: 14-15.
Workplace safety and health: Enhancing OSHA’s records audit process could improve accuracy of worker illness and data. GAO Report 10-10.
Washington, D.C.: Government Accountability Office, 2009.
26
Sonetics Corporation White Paper No. SO12-02.01_final | www.soneticscorp.com | 800-833-4558
APPENDIX A
Wireless System Requirements
When looking for a wireless headset system, it is helpul to understand the key features and functionalities of
each system. The following table provides a top-level look at the major recommended requirements for wireless
systems used in crane operations, and how Sonetics’ solutions address these recommendations.
Feature
Sonetics
Truly wireless?
Completely self-contained wireless headsets; no belt pack or radio wire is necessary
Range
1600 feet line-of-sight
DECT or Bluetooth?
DECT 6.0, interference-free communication with 30 times the coverage area of
Bluetooth
Full duplex available?
Yes; full-duplex and hands-free
Configurable duplex?
Fully configurable with a variety of push- and toggle-to-talk options
Noise reduc tion rating
24+
Radio-c om patible?
Yes, with over 400 m odels of radios
Num ber of users
1-60
Sec ure?
Yes, all signals are digital and fully encrypted
Comfortable?
Designed for comfort with ComLeather-over-memory-foam ear seals
Ingress protection rating
I P6 5
Customer support
Dealers receive extensive training; expert technical phone support is available 10
hours per day, five days per week
Battery life
24 hours of operation on a two-hour c harge
Operating tem perature
-40º to +158º F
Microphone
Noise-cancelling electret on flex boom for crystal clear communications
Battery charger
Heavy-duty charger included
Warranty
Two-year standard; expandable to five years with ComCare™ service
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27
7340 SW Durham Rd. • Portland, OR 97224 USA
800.833.4558 • www.soneticscorp.com • [email protected]
28
Copyright ©2012 by Sonetics Corporation.
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