TRENCH
COLLAPSE ACCIDENTS & EXCAVATION CAVE-IN INJURIES & DEATHS
Trench collapses,cave-ins and
side wall collapses are perhaps the most feared hazards in the trenching
and excavating industry. But other potentially fatal excavation dangers
exist, including asphyxiation due to lack of oxygen in a confined space,
inhalation of toxic fumes, suffocation from the crushing weight of soil on
the buried worker, falls, and drowning. Electrocution or explosions can also
occur when workers contact underground utilities.OSHA requires that  workers
in trenches and excavations be protected, and that safety and health programs
address the variety of hazards they face. Excavation cave ins are a major
source of fatalities within the construction industry. Trenching accidents on
U.S. construction sites account for an estimated 100 fatalities per year, with
at least 11 times as many workers injured.
The man
in the photo to the left is in a very dangerous situation. He is alone
at the bottom of a deep vertical trench. The excavated soil
has been stockpiled at the very edge of the trench, adding to the pressure on
the trench walls. Vibrations from any backhoe or other heavy equipment
near the perimeter of the excavation can increase the likelihood of a
cave-in. Neither a ramp nor ladder has been provided for the worker to escape.
Finally there is nothing to protect him from a cave-in; there is no sloping back
of the trench walls, no shoring of the walls, and
no shielding or retaining
devices, such as a trench box. Lastly, there does not appear to be
any fall protection devises, fencing or barricades to keep other
workers from falling into the trench itself or to accidental filling in of
excavated soils.
EXCAVATION
INJURIES & DEATHS
 Workers in
trenches, excavations and other restricted spaces are presented with the
high risk of cave in accidents, falls, wall collapse, risks of oxygen
depletion, toxic fumes, and water accumulation. Trench wall protective
systems or boxes help protect workers while working in trenches or
excavations. When a side wall collapses or the trench caves in, the worker down
in the trench can receive serious personal injuries or die from being
crushed by the soil or ground from the cave-in, die from asphyxia from lack
of oxygen,suffocation, be seriously injured from falls into the trench, be
injured from falling debris, receive serious or fatal injuries from being struck
by trenching equipment or backhoes operating in or nearby the trench or
hole being excavated and die from poisonous fumes and gases in the trench
itself.
TRENCH AND EXCAVATION
CAVE IN ACCIDENTS PREVENTION
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READ, UNDERSTAND & APPLY
APPLICABLE SAFETY RULES FOUND IN 29 CFR 1926.652
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Evaluate soil conditions and select
appropriate protective systems;
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Use retaining devices, such as a trench box,
that will extend above the top of the trench to prevent equipment and spoils
from falling back into the excavation;
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Where the site does not permit a 2-foot set
back, spoils may need to be temporarily hauled to another location;
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Have a qualified and competent person
trained in trench safety with authority to remove workers from excavation
immediately or shut down job site if conditions warrant;
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Construct protective systems in accordance
with the standard requirements;
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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 system.
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Test for low oxygen, hazardous fumes and toxic
gases, 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 protection if necessary;
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Provide safe access into and out of the
excavation;
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Provide appropriate protections if water
accumulation is a problem;
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Inspect the site daily at the start of each
shift, following a rainstorm, or after any other hazard-increasing event;
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Keep excavations open the minimum amount of
time needed to complete operations;
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Protect employees from
loose rock or soil;
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Place spoils, materials, and equipment set
back a minimum of 2' from edge of excavation;
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Place barriers, fences or barricades at all
excavations, wells, pits, shafts, etc;
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Erect walkways and bridges
over excavations 6' or more in depth and equip them with guardrails;
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Prohibit employees from working or walking
under suspended loads;
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Prohibit employees from working on faces of
sloped or benched excavations above other employees;
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Require all employees in trenches to wear hard
hats;
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When employees enter deep confined excavation
they must wear safety harness and life lines;
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Employees trained in the use of Personal
Protective and Emergency Response Equipment;
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Keep excavations open the minimum amount of
time needed to complete operations;
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Precautions must be taken to prevent
accumulation of water and the dangers to trench workers;
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Inspect the site daily at the start of each
shift, following a rainstorm or snow storm, or after any other
hazard-increasing event
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Testing conducted to ensure
that atmosphere remains safe to breath and non-explosive and/or
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Utility companies contacted and/or utilities
located, marked and protected from contact with excavators and backhoe
equipment.
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ACTUAL TRENCH ACCIDENT CASES
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LOOSE SANDY SOIL TRENCH CAVE
IN ACCIDENT- An employee was in a trench installing
forms for concrete footers when it caved-in, causing fatal injuries.
The
trench, which was 7 1/2 feet deep, was in loose, sandy (Type
C) soil, and no inspection was conducted prior to the start of
the
shift.
-
RETAINING
WALL (TRENCH WALL) COLLAPSES -
A 27-year old male laborer (victim) died after being trapped in
soil over his head as a result of a trench that caved-in.The
victim was buried in soil over his head. The coroner's report
stated the cause of death to be asphyxia.The victim was digging
out the bottom of the trench in order to expose an existing drain
pipe. On one side of the trench was a retaining wall and the
other
side was a dirt wall which was part of a hillside. He and another
laborer were piling the dirt on the hillside above the east wall
of the trench. Later the other laborer pulled up buckets filled
by the decedent with the spoils placing them on the hillside above
the trench wall as well as on the south side of the excavation.
The trench wall that collapsed was not shored or otherwise
protected from earth movement. The soil had been previously
disturbed in the area of the trench. There was no competent person
to check the soil and excavation at the site and no initial hazard
assessment was performed. The victim received no training from
the
company for whom he worked.
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9 FOOT DEEP TRENCH WALL COLLAPSE KILLS WORKER -
Two employees were installing 6" PVC pipe in a trench
40' long x 9' deep x 2' wide. No means of protection was
provided in
the vertical wall trench. A cave-in occurred, fatally injuring
one employee and causing serious facial injuries to the
other.
- UNPROTECTED TRENCH WALL COLLAPSE-
An inadequately protected trench wall collapsed, killing
one employee who had just gotten into the trench to check grade
for
installation of an 8" sewer line. The trench was 2
0-25
feet deep and had been benched about one bucket-width (4
feet) on
each side. At the time of the collapse a backhoe was still
extracting soil from the trench.
- INADEQUATE SHORING
OR TRENCH PROTECTION DEVISE USED -Four employees were in an excavation 32' long x
7' deep x 9' wide boring a hole under a road. Eight-foot steel
plates used as shoring we
re placed against the side walls of the
excavation at about 30-degree angles. No horizontal bracing
was used. One of the plates tipped over, crushing an employee
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WORKER IN TRENCH DIES
FROM FUMES - In a trench 6 feet deep x 32 inches wide, an
employee was applying a waterproofing primer containing methyl
chloroform and 1,4-dioxane to the foundation of a house. The
employee was overcome by the fumes, and later died of
trichloroethane intoxication. No one had tested the atmosphere in
the trench, the employees were not provided with respiratory
protection, and mechanical ventilation was not used.
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TRENCH WALL CAVE- IN -Two
employees were laying pipe in a trench 12-feet deep, when one of the
employees saw the bottom face of the trench move. He jumped out of the way
along the length of the trench; the other employee was fatally injured as
the wall caved-in. The walls of the trench were not sloped, and no means
of emergency egress were provided.
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TRENCH NOT SHORED OR SLOPED
- In a 15-foot deep trench, which was not shored or sloped properly, two
workers were laying sewer pipe. The only means of egress was by climbing
the backfill. While exiting the trench, one of the workers was trapped by
a small cave-in. The second employee tried to extricate him, but a second
cave-in occurred, trapping the second employee at the waist. The second
cave-in actually caused the death of the first employee; the second
employee sustained a hip injury.
TRENCH ACCIDENTS, CAVE IN & WALL COLLAPSE
LAWSUITS
 If you
or a loved one have suffered a serious injury or accidental death as a
result of a trench wall / excavation cave-in or retaining
wall collapse or any other serious injury resulting from unsafe
trenching practices, then you may have a right to file a lawsuit case
against the negligent parties and companies involved. Call now and get your
questions answered. Talk to a Board Certified Personal Injury
Trial Lawyer FREE
CONFIDENTIAL CONSULTATION at 1-800-883-9858 or
1-800-468-4878 (Toll Free)
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