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6.8 Management, Operation, and Maintenance of Distribution Systems 221
in diameter with the straight section 3 ft (0.91 m) long and the other section a 90-degree
angle section or “L” joint. The straight piece weighed about 10 lb (4.54 kg) and the “L”
joint weighed between 30 and 40 lb (14 and 18 kg).
The victim and apprentice plumber were in the trench trying to assemble the 3-foot
(0.91-m) section to the 90-degree “L” joint but there was not enough room to work and
there was still a large amount (6 to 8 in. or 150 to 200 mm) of water in the hole. They de-
cided it would be easier to work on connecting the two pieces outside the trench and then
return the assembled unit to the trench to connect to the other pipe lines. To get the pipes
out, they decided to place them in the bucket and have them raised out of the trench.
The bucket of the backhoe was positioned about 4 ft (1.4 m) down in the trench close
to the pipe line. The victim was facing east about 1 ft directly to the left and in the line of
contact with the bucket. The apprentice plumber was also to the left of the bucket but out
of its reach and was facing west looking at the victim.
The “L” pipe had just been placed in the bucket by the victim and apprentice plumber
when, unexpectedly, the 255-lb (102-kg) bucket with the approximately 40 lb (18 kg) of
pipe swung swiftly to the left and struck the victim in the left arm and upper chest, shoving
him about 6 in. and pinning him into the south trench wall. The apprentice plumber yelled
at the operator who maneuvered the bucket to the right to release the victim, who then
slumped to the ground, groaning.
The operator called emergency personnel, who arrived at the scene in 3 minutes. The
victim had no pulse or respiration. Ambulance personnel removed the victim from the hole
and transported him to a hospital where he was pronounced dead of blunt force injuries to
the chest. The manner of death was determined to be accidental. Hospital personnel told a
police officer that death was caused by a ruptured myocardium (heart).
Recommendation #1: Employers should ensure that backhoe operators shut down back-
hoes according to the manufacturer’s directions and direct workers to remain an adequate
distance from operating backhoes. According to the apprentice plumber, the backhoe was
running with its bucket positioned about 4 ft (1.22 m) down in the trench directly in line of
contact with the victim. If the backhoe had been shut down properly and had workers been
directed to remain an adequate distance from the backhoe the fatality may have been averted.
Recommendation #2: Employers should designate a competent person to supervise
trench activities. In work involving trenches the Occupational Safety and Health
Administration (OSHA) requires a competent person to be responsible for trench activi-
ties. A competent trench worker should be able to perform the following duties:
1. View the “big picture” and recognize by proper assessment the present and poten-
tial hazards at a site.
2. Classify soil types and changes to the soil composition.
3. Determine the need for sloping, shoring, or shielding.
4. Examine and approve or disapprove material or equipment used for protective systems.
5. Identify utilities located parallel to or crossing the trench.
6. Conduct daily inspections prior to the start of work and as needed. Inspect the
adjacent areas and protective systems for indications of failure and hazardous
atmospheres and conditions.
7. Inspect the trench after every rainstorm or other hazard-increasing occurrence.
8. Determine suitability of job site for continued work after water accumulation.
Having employees in the trench when the backhoe was running was a hazardous condi-
tion for several factors: the vibration of the soil caused by the running machine, the overhead