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Example:
If inspecting a tank that is 6 m
(20 ft)
tall, the No Entry Fall Zone radii
must be no smaller than 3 m
(10 ft)
from the area below the area of crawler
operation.
5.2.2. Tether Requirements and Attachment
When used at a height greater than 2 m
(6 ft)
, the
NAVIC
crawler MUST be
tethered with a proper tether system to prevent the crawler from falling. The
tether system must:
►
be capable of safely suspending the crawler from above in case the crawler
detaches from the inspection surface;
►
have sufficient capacity to catch and hold a 70 kg
(150 lb)
load;
►
include a mechanism
(i.e. self retracting inertia reel fall arrester)
or person to
continuously take up slack in the tether as the crawler moves;
►
include a lifting hook with a safety latch to prevent accidental disconnection.
The hook must be free of sharp edges that may cut or abrade the provided
lifting sling.
Before placing the crawler on the surface to be inspected
(e.g. tank)
, attach the
provided lifting sling to the
NAVIC
and then hook the tether hook to the lifting
sling.
WARNING!
FALLING OBJECT HAZARD
.
Failure to comply with the warnings, instructions, and
specifications in this manual could result in
SEVERE
INJURY
or
DEATH
.
WARNING!
Do
NOT
operate or place
crawler on a surface higher than 2 m
(6 ft)
without a
proper tether held taut at all times.
WARNING!
Hook the tether hook to the
provided lifting sling
BEFORE
placing the crawler on
the surface to be inspected
(e.g. tank)
.
IMPORTANT
:
Tether hook must have a safety latch to prevent
accidental disconnection.
CAUTION!
The overhead attachment point
for the tether must be located as close as possible to
a location directly above the crawler to minimize
dangerous swinging of the crawler should it detach
from the inspection surface.