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222 Chapter 6 Water Distribution Systems: Components, Design, and Operation
load of the bucket and boom, and the limited visibility by the backhoe operator of activities
in the trench. Under any of these conditions, a competent person would remove the ex-
posed employees from the trench until hazards have been controlled.
Recommendation #3: Employer should ensure that workers are protected from cave-ins
by an adequate protective system. A protective system designed for the soil conditions found
in this excavation could have included a trench shield (also known as a trench box), shoring,
or a combination of shoring and shielding. Employers can consult with manufacturers of pro-
tective systems to obtain detailed guidance for the appropriate use of these products. In this
incident, no protective system had been placed at any point in the 31-ft (9.45-m)-long trench.
Although the victim in this incident was not killed because of a trench cave-in, protective
systems should always be used in trenches greater than 5 ft (1.52 m) deep.
6.8.3 Welder Killed Following a 100-ft (30-m) Fall from a Water Tower
A welder was killed after falling 100 ft (30 m) from a leg of a municipal water tower. The
victim was a 25-year-old male welder who had been working for the company as a tower
hand for 4 years. He had previously worked as a welder for a municipality. The incident
occurred while the victim and a coworker were welding antenna support brackets onto the
leg of the tower. The victim apparently disconnected his fall protection and was climbing
the leg of the tower when he fell approximately 100 ft (30 m) to the ground.
The water tower consisted of a 40-ft (12.2-m)-diameter steel water tank mounted on
six structural steel legs. Each of the legs was made of welded plate steel with structural
steel braces. Although not specifically designed for climbing, these braces were spaced
near enough that they could be used as a ladder. The top of the tower was accessed by a
steel ladder with a ladder cage that was built on one of the legs. A pump house was located
near the bottom of the ladder and was the terminating point for a number of antennas and
utility cables leading from the tower.
The day of the incident was clear and sunny. The foreman and three tower hands ar-
rived in the morning and set up the hoist system on the tower leg. The victim was using a
lineman’s belt that he owned and had modified to make the seat strap more comfortable.
Work proceeded uneventfully until the victim and a coworker were finishing the welding
of a bracket about 100 ft (30 m) up the tower leg. The coworker stated that they had been
up on the leg for a while and that the victim had been tied off to the leg at the same loca-
tion for about 15 minutes before the incident. The coworker had completed his weld and
handed the welding equipment down to the victim, who was working below him. The vic-
tim then finished his weld and began to chip and paint. Noticing that there was a fault in
the weld above his head, the victim called down to the foreman to start up the welder so he
could redo some spots. He then started to climb up the tower. As the foreman turned to
start the machine, he heard the victim yell and saw him fall to the ground. The police and
emergency medical services personnel were called and arrived within a few minutes of the
fall and began treating the victim, who was still breathing. During this time the shaken
coworker was lowered to the ground on the material hoist line. The victim was transported
to the local medical center where he was pronounced dead.
Investigators concluded that these guidelines should be followed in order to prevent
similar incidents in the future:
1. Employers must thoroughly plan all work and perform a job hazard analysis of the
site prior to starting work.
2. When practical, employers should provide and require the use of a stable work
platform for working at elevated worksites.
3. Employers should provide a system of fall protection that protects employees at all
times when working at elevations.