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Printing Instructions |
Aurora OSHA Construction News
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US Department of Labor
North Aurora, IL Area Office |
Volume 3, Issue 2
Fall 2002 |
Inside this issue:
Trenching Still A Concern
Construction Partnership Signed
Combined Rescue Drill a Success
Did You Know?
Fatalities and Injuries in Illinois
Most Frequently Cited
Top Ten Reasons for Noncompliance
Protective Systems for Trenches
Trenching and the Competent Person
Trenching Still A Concern
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| Luckily, this worker made it out of the trench alive. |
Why do knowledgeable people choose not to use cave-in protection? Lately the
answer from employers is that cave-in protection would have been
"inconvenient" to use.
While some of you know that is not what you want to tell an OSHA Compliance
Officer, one employer actually said: "If the box (trench box) would have
fit--we would have used it".
We are finding more and more trenching contractors not in compliance with the
trenching standards. In fact, lack of cave-in protection was the #2 cited
violation this past year.
A protective system must be used if an excavation is 5 feet or greater in depth.
The three most commonly used types of protective systems are: shoring,
shielding, and sloping.
Each of these protective systems are acceptable to OSHA: it is up to the
competent person to determine which method will be most effective for the job.
(See for more on
protective systems.)
If it not acceptable (or legal) to not use cave in protection because of
convenience.
Due to the serious hazards involved, and the fact that most contractors we
inspect are not in compliance, most of this newsletter will be devoted to
trenching hazards and corrective methods.
Construction Partnership Signed
A partnership to reduce injuries, illnesses and deaths in the hazardous
residential construction industry was signed by the Occupational Safety and
Health Administration (OSHA), the On-Site Safety and Health Consultation Program
of Illinois (DCCA), the Residential Construction Employers Council (RCEC) and
the Northeast Illinois District Council of Carpenters Apprenticeship and
Training Program.
The partnership will provide members with information and guidance that will
help enhance employee safety programs, including ways to minimize hazards from
falls. Members will work together to develop training on safety and health
issues specifically aimed at residential construction.
Members of the RCEC will be encourages to participate in programs such as
Consultation's Safety and Health Achievement Recognition Program (SHARP) and the
Voluntary Protection Program (VPP).
A team of representatives from the agencies will meet regularly to set goals and
objectives and track progress.
Combined Rescue Drill a Success
The technical rescue teams of Aurora, North Aurora and Batavia Fire Departments
came together this October in front of the Home Depot on Orchard Road for what
appeared to be a construction accident. Fortunately, it was a preplanned trench
rescue drill to test the skills and abilities of the three fire departments
technical rescue teams.
According to Lt. Mark Lockwood, coordinator of Aurora's rescue team, the three
departments' train together on a quarterly basis on different technical rescue
disciplines. "The joint training allows us to be well prepared in the event
of an actual incident," Lockwood says.
Crews simulated that a construction crew was digging a hole when part of the
earth wall collapsed on a victim. The technical rescue teams used specialized
equipment that was placed in the hole to prevent more dirt from falling on the
victim. Rescue workers then entered the protected area, treated the victim, and
removed the victim using rope rescue equipment. "Sixty-fire percent of all
would be rescuers become victims because proper safety procedures are not
followed" Lockwood says. "It seems like it takes a long time, but we
must follow the safety procedures to protect the rescuers and the victim from
further injury."
 The team practiced several different scenarios from 8 a.m. to noon. The Home
Depot site was chosen because of their extensive help in developing a disaster
and recovery plan with the technical rescue team.
The joint rescue team was established 2 years ago to address the needs of
special rescues in the area. According to Assistant Chief Mark Bozik, the
combined team is capable of handling such incidents as trench rescues, building
collapses, confined space rescues, elevated or rope rescues, and mass casualty
incidents.
The combined team is 1 of only 14 teams that is recognized by the state for
technical rescue" Bozik says. "The team could be called anywhere in
the State in the event of a major incident. Residents should be proud that this
highly trained team is in their community."
Did You Know?
Steel Erection eTool
Despite being covered since 1971 under the original steel erection standard,
America's 56,000 steel erectors continued to suffer 35 fatal accidents per year,
a rate of one death per 1,600 workers. OSHA estimates that 30 of those deaths,
as well as nearly 1,150 annual lost-workday injuries, will be eliminated by
compliance with provisions of the new standard, developed with industry and
labor through negotiated rulemaking. This eTool has been created to educate
employers and workers about the revised standard.
U.S. v Walter Marble
Federal District Court issued its sentencing order in this criminal prosecution
of the owner of a construction company who made false statements to OSHA
inspectors and furnished false documents to cover up the fact that he in fact
employed a worker who was killed at a jobsite. Following a plea agreement
entered last August, the court sentenced Walter Marble to five months
confinement with the Bureau of Prisons to be followed by five months home
confinement and two years of supervised release. Marble was also fined $3,000
and assessed costs of $100. Mr. Marble plead guilty to one count of corruptly
obstructing the due administration of the law in an OSHA investigation by
causing a false contract, a false invoice, and a letter containing false
statements to be submitted to OSHA for the purpose of corruptly influencing
OSHA's determination of whether an individual killed in a trench collapse on
November 4, 1999 was working as an independent contractor or was an employee.
L.E. Meyers Co. Indicted in Deaths of Two Workers
This December an electrical contracting firm and its parent company were
indicted in connection with the deaths of two employees working on high-voltage
lines three years ago. The misdemeanor charges allege the L.E. Meyers Co. and
its parent, MYR Group Inc., both based in Rolling Meadows, willfully failed to
properly train and supervise the workers, who were killed in separate incidents
in urban Chicago.
The companies were charged with two counts each - one for each death - of
allegedly violating Occupational Safety and Health Administration regulations.
If convicted, the two companies face fines of up to $2 million and a maximum of
5 years of probation.
Fatalities and Injuries in Illinois
The following is a synopsis of some of the accidents we investigated during the
past few months:
- Three employees were in the process of dismantling a Morgan scaffold at
a Rockford, Illinois jobsite. Initially all 3 employees were working from
the platform that was positioned approximately 7 feet above grade. Two of
the employees vacated the platform to return to the ground. One of the
employees who was considered the competent person left to removed the ladder
that was leaning against the platform. The second worker who was not being
monitored began to remove the last set of cross-braces at grade level These
cross-braces were the last guarantee of stability for the scaffold system and
should not have been removed until the worker on the platform reconnected
the cross-braces at platform level. When the unaccounted for worker at ground
level had removed one of the connection points for the cross-braces the
scaffold platform collapsed throwing the lone worker on the platform to the
ground where he suffered a compound fracture of the right forearm.
(Rockford)
- A crew was installing 48" water main in a trench
approximately 10' deep. There was a 8' trench box in the trench for cave-in
protection, but the North end of the trench box was not closed off. An
employee working towards the north end of the trench, while sill in the
confinement of the box, was struck by dirt and rocks when there was a
cave-in at the north end of the trench. Loose dirt and rock came into the
box through the north end opening. The 33 year old construction laborer had
the wind knocked out of him, and was taken to the hospital for examination.
He did not sustain any serious injuries. (West Chicago)
- A 35 year
old self-employed worker was tuckpointing while working on a two point
suspension scaffold 15 feet from ground level. The left side of the scaffold
broke from off the parapet on the roof. The worker fell and hit his head and
died from the fall. (Chicago)
- A worker was trapped by a 16
horsepower track-mounted walk-behind cable plow, while attempting to off
load this machine from a Chevy Astro Van. The employee was trapped between
the machine's handlebars and the roof of the van at the rear cargo doors.
The machine engine was started, and the clutch and transmission engaged in
anticipation of backing the 850 lb machine down the ramp. The employee was
discovered by a co-worker. The engine of the cable plow was running at half
throttle and the rubber tracks were slipping on the truck bed. Initial
attempts to free the decedent failed. (Waukegan)
- A 21 year-old
construction laborer was killed while working on a second story addition to
a residence. The walls had been erected and the roof was being framed. Two
sheets of plywood had been temporarily nailed down on top of the joists. The
deceased walked onto the unsupported portion of temporary plywood deck and
fell to the ground when the plywood broke. (Elmwood Park)
- A 39 year
old construction laborer working for a masonry company was working in a room
where a tubular frame scaffold had been erected. A scaffold leg was placed
on top of an extension cord. The extension cord was being used to power a
industrial fan on the opposite side of the room. The weight of the scaffold
cut through the extension cord, energizing the scaffold. As the worker
attempted to re-enter the room, he passed through the door frame and the
scaffold and was electrocuted. (Palos Heights)
- A 36 year-old
construction worker died after falling 12-13 feet from a sling. A 14 foot
long synthetic web sling was attached to the guardrail of aerial lift. The
lift was raised vertically to removed the slack in the sling. The worker,
standing on top of the 31 foot tall steel silo, stepped into the bottom loop
of the sling. The employee was lifted up on the sling and then lowered
through a 20" x 20" opening in the top of the silo. The employee
was lowered approximately 9 feet into the silo when two employee, standing
outside the silo heard the employee inside the silo yelling, "get me
out of here." The employees on the ground level motioned for the lift
operator to raised the employee out of the silo. As the lift operator began
raising the lift, the employees on the ground heard a thumb inside the silo.
The employee inside the silo had fallen 12-13 feet off the sling to the
bottom of the silo. (Orion)
- Employees were preparing to perform
abrasive blasting work. The employees were instructed by the site foreman to
don their type CE abrasive blast respirators. Upon the foreman's return to
the area, he found the workers unconscious. The supplied air line for the
respirator shad been connected to a plant air line labeled "compressed
air". After investigating, it was found that the line was 99.9%
nitrogen. Both employees were hospitalized. (Bartonville)
- Roofers
were unloading shingles from a boom onto the roof of a residential house
under construction. The victim was apparently trying to step from the roof
to a scaffold pick located on the front of the house when he fell
approximately twenty-two feet to the ground below. The victim was taken to
the hospital with fatal injuries.
Most Frequently Found Hazards - Illinois
The "top ten" cited violations for construction are listed for the
state of Illinois during this past fiscal year (October 2001 - September 2002).
Lack of cave-in protection landed at number 2 on the list, with over $350,000 in
penalties issued. This was, by far, the most penalized standard last year. 16%
of the violations were cited as "Repeat". This means that the company
inspected had been cited for that exact same violation (or hazard) during the
past three years.
Another area consistently cited was fall protection - whether from scaffolds,
roofing or residential construction sites.
We will continue our emphasis in these areas next year.
Top Ten Reasons for Noncompliance
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| This is not a trench you would want to be in —even with a ladder. |
After a citation is issued, employers frequently have an informal conference
with the area director to discuss violations. Some of the "reasons"
for noncompliance are quite interesting - and sad. Listed here are the "top
ten" reasons for noncompliance.
| The employer is responsible for
frequent and regular inspections of the job site. Any recognized
hazards must be taken care of. |
The job was only going to take a minute.
Guardrails were order and on the way to the job site - we just decided to start
work without them.
We have guardrails on the other site.
We have been doing this work for 20 years and would not expose ourselves to
hazards. (the employee was in a 10-foot deep trench without cave-in protection).
The soil was good.
(The employer is responsible for frequently and regular inspections of the job
site. Any recognized hazards must be taken care of.)
We never used that equipment (photos show employees using the equipment during
the inspection).
I left my personal protective equipment in the other truck.
Our foreman has a lot of experience and is an OSHA competent person (then why
did he tell us that it was OK to work on a 15-foot high scaffold without
guardrails).
That wasn't our employee.
And the number 1 reason:
OSHA made us nervous.
Protective Systems for Trenches
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| A shoring system could have been used in
this trench to protect the workers. |
Soil is heavy. A cubic foot can weigh as much as 114 pounds, and a cubic yard
can weigh over 3,000 lbs. - a little more than a Volkswagen Beetle. Most workers
don't realize the force that will hit them when a cave-in occurs. A person
buried under only a few feet of soil can experience enough pressure in the chest
area to prevent the lungs from expanding. Suffocation can take place in as
little as three minutes. Heavier soils can crush the body in a matter of
seconds.
Protective systems are methods of protective workers from cave-ins of material
that can fall or roll into an excavation, or from the collapse of nearby
structures. If an excavation is less than 5 feet deep, OSHA does not require a
protective systems unless the competent person sees signs of a potential
cave-in. (It is important to remember that a wall collapse in a trench four and
1/2 fee deep can still have serious results!)
For trenches between 5 feet and 20 feet deep, shoring and sheeting, shielding,
sloping and benching are all acceptable protective measures. It is up to the
planners of the construction project and the competent person on site to
determine which systems will will work best. If an excavation is greater than 20
feet deep, a registered professional engineer must design the protective system.
Shoring systems are structures of timber, mechanical, or hydraulic systems that
support the sides of an excavation which are designed to prevent cave-ins.
Sheeting is a type of shoring that keeps the earth in position. It can be driven
into the ground or work in conjunction with a shoring system. Driving sheeting
is most frequently used for excavations open for long periods of time. Another
type of sheeting, in which plates or shoring grad plywood (sometimes called
Finland form) is used in conjunction with strutted systems such as hydraulic or
timber shoring. These strutted systems are also referred to as active systems.
The most frequently used strutted system involves aluminum hydraulic shores
which are light-weight, re-usable and installed and removed completely from
above ground.
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| A trench box is being used—but what is wrong with this picture? Hint-what would happen if the soil on top collapsed? |
A shield, also known as a trench box, is another common protective system used
by contractors. Trench boxes are not designed to prevent cave-ins, but rather
serve to "shield" workers within the structure should a cave-in occur.
This is an excellent choice when placing continuous installations, as in pipe
laying. The box is placed in the trench and dragged along with the progress of
the work. A few important points about shields:
- Personnel should be out of the box and above ground when the shield is
being moved. You could be caught between the moving box and fixed objects(s);
- The
top of the shield should extent at least eighteen (18) inches above the
level of any materials that could cave or roll into the trench;
- Some
shields are designed to be stacked, one on top of another. Never stack
shields that are not designed for that purpose, and do not stack shields
from different manufacturers, as the may not be compatible.
- The
forces of a cave-in can literally push a box sideways, causing a crushing
hazard. After a box is positioned for the work, the voids between the box
and the trench wall should be filled with excavated material to prevent
displacement caused by a cave-in.
- Shielding should always be used
according t manufacturer's tabulated data.
With
both shoring and shielding, workers are only protected as long as they stay
within the confines of the system.
Sloping and benching are another means of protecting workers from cave-in
hazards. Sloping is a method of cutting back the trench walls at such an angle
that there is little chance of collapse. This is referred to an an "angle
of repose", and must be suitable to the type of soil.
There are very few applications where sloping and/or benching can be used. Why?
The lack of available space. Many excavations are dug in right-of-ways where the
presence of other utilities and traffic become major considerations. If the
location to be excavated has been previously disturbed, as it frequently is
along a right-of-way, the soil type swill very likely be classified as
"C". with Type C soil, the excavation walls must be sloped back on
each side of the excavation one and one-half feet for every foot of depth.
Trenching and the Competent Person
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| Yes—this is a violation. The excavation is
undercutting the street and the front end loader only adds to the problem. |
Pre-job planning is vital to accident-free trenching. Safety cannot be
improvised as work progresses.
Regardless of the depth of the excavation, OSHA requires a competent person to
inspect conditions at the site on a daily basis. Inspections must be made as
frequently as necessary during the progress of the work, to assure that the
hazards associated with excavations are eliminated, before workers are allowed
to enter the trench.
The following concerns must be addressed by a competent person:
- Evaluate soil conditions and select appropriate protective measures.
- Construct
protective systems in accordance with the standard requirements.
- Preplan;
contact utilities (gas, electric) to locate underground lines, plan for
traffic control if necessary, determine proximity to structures that could
affect choice of protective systems.
- Test for low oxygen, hazardous
fumes, and toxic gasses, especially when gasoline engine-driven equipment is
running, or the dirt has been contaminated by leaking lines or storage
tanks. Insure adequate ventilation or respiratory equipment if necessary.
- Provide
safe access into and out of the excavation.
- Provide appropriate
protections if water accumulation is a problem.
- Inspect the site
daily at the stat of each shift, following a rainstorm, or after any other
hazard-increasing event.
- Keep excavations open the minimum amount of
time needed to completed operations.
Should a third-party be required to stop work, or the
designated competent person does not halt unsafe acts and conditions, this
individual is not acting "competently" within the meaning of the
standard.
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