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6.8 Management, Operation, and Maintenance of Distribution Systems
255 lb (102 kg) bucket with the approximately 40 lb (18 kg)
remove the exposed employees from the trench until hazards
of pipe swung swiftly to the left and struck the victim in the
have been controlled.
left arm and upper chest, shoving him about 6 in. and pin-
Recommendation #3: Employer should ensure that
ning him into the south trench wall. The apprentice plumber
workers are protected from cave-ins by an adequate pro-
yelled at the operator who maneuvered the bucket to the
tective system. A protective system designed for the soil
right to release the victim, who then slumped to the ground,
groaning.
conditions found in this excavation could have included a
The operator called emergency personnel, who arrived
trench shield (also known as a trench box), shoring, or a
combination of shoring and shielding. Employers can consult
at the scene in 3 min. The victim had no pulse or respira-
tion. Ambulance personnel removed the victim from the hole
with manufacturers of protective systems to obtain detailed
and transported him to a hospital where he was pronounced
guidance for the appropriate use of these products. In this
dead of blunt force injuries to the chest. The manner of Under any of these conditions, a competent person would
incident, no protective system had been placed at any point
death was determined to be accidental. Hospital personnel in the 31-ft (9.45-m)-long trench. Although the victim in this
told a police officer that death was caused by a ruptured incident was not killed because of a trench cave-in, protective
myocardium (heart). systems should always be used in trenches greater than
Recommendation #1: Employers should ensure that 5 ft (1.52 m) deep.
backhoe operators shut down backhoes according to the man-
ufacturer’s directions and direct workers to remain an ade- 6.8.3 Welder Killed Following a 100 ft (30 m) Fall
quate distance from operating backhoes. According to the
from a Water Tower
apprentice plumber, the backhoe was running with its bucket
positioned about 4 ft (1.22 m) down in the trench directly A welder was killed after falling 100 ft (30 m) from a leg of
in line of contact with the victim. If the backhoe had been a municipal water tower. The victim was a 25-year-old male
shut down properly and had workers been directed to remain welder who had been working for the company as a tower
an adequate distance from the backhoe the fatality may have hand for 4 years. He had previously worked as a welder for
been averted. a municipality. The incident occurred while the victim and
Recommendation #2: Employers should designate a a coworker were welding antenna support brackets onto the
competent person to supervise trench activities. In work leg of the tower. The victim apparently disconnected his fall
involving trenches the Occupational Safety and Health protection and was climbing the leg of the tower when he fell
Administration (OSHA) requires a competent person to be approximately 100 ft (30 m) to the ground.
responsible for trench activities. A competent trench worker The water tower consisted of a 40 ft (12.2 m) diameter
should be able to perform the following duties: steel water tank mounted on six structural steel legs. Each
of the legs was made of welded plate steel with structural
1. View the “big picture” and recognize by proper
steel braces. Although not specifically designed for climbing,
assessment the present and potential hazards at a site.
these braces were spaced near enough that they could be used
2. Classify soil types and changes to the soil composi- as a ladder. The top of the tower was accessed by a steel ladder
tion. with a ladder cage that was built on one of the legs. A pump
3. Determine the need for sloping, shoring, or shielding. house was located near the bottom of the ladder and was the
terminating point for a number of antennas and utility cables
4. Examine and approve or disapprove material or
leading from the tower.
equipment used for protective systems.
The day of the incident was clear and sunny. The foreman
5. Identify utilities located parallel to or crossing the
and three tower hands arrived in the morning and set up
trench.
the hoist system on the tower leg. The victim was using a
6. Conduct daily inspections prior to the start of work lineman’s belt that he owned and had modified to make the
and as needed. Inspect the adjacent areas and protec- seat strap more comfortable. Work proceeded uneventfully
tive systems for indications of failure and hazardous until the victim and a coworker were finishing the welding of
atmospheres and conditions. a bracket about 100 ft (30 m) up the tower leg. The coworker
7. Inspect the trench after every rainstorm or other stated that they had been up on the leg for a while and that
hazard-increasing occurrence. the victim had been tied off to the leg at the same location
for about 15 minutes before the incident. The coworker had
8. Determine suitability of job site for continued work
completed his weld and handed the welding equipment down
after water accumulation.
to the victim, who was working below him. The victim then
Having employees in the trench when the backhoe was finished his weld and began to chip and paint. Noticing that
running was a hazardous condition for several factors: the there was a fault in the weld above his head, the victim called
vibration of the soil caused by the running machine, the down to the foreman to start up the welder so he could redo
overhead load of the bucket and boom, and the limited vis- some spots. He then started to climb up the tower. As the
ibility for the backhoe operator of activities in the trench. foreman turned to start the machine, he heard the victim yell