“working aloft chit” signifies that all equipment is in a
nonradiating status (the equipment is not moving). The
person who signs the chit should ensure that no RF
danger exists in areas where personnel are working.
Nearby ships or parked aircraft are another source
of RF energy that must be considered when checking
work areas for safety. Combustible materials can be
ignited and cause severe fires from arcs or heat
generated by RF energy. RF radiation can detonate
ordnance devices by inducing currents in the internal
wiring of the device or in the external test equipment, or
leads connected to the device.
You should always obey RF radiation warning
signs and keep a safe distance from radiating antennas.
The six types of warning signs for RF radiation hazard
are shown in figure 2-40.
RF BURNS
Close or direct contact with RF transmission lines
or antennas may result in RF burns. These are usually
deep, penetrating, third-degree burns. To heal properly,
these burns must heal from the inside to the skin surface.
To prevent infection, you must give proper medical
attention to all RF burns, including the small “pinhole”
burns. Petrolatum gauze can be used to cover burns
temporarily before the injured person reports to medical
facilities for further treatment.
DIELECTRIC HEATING
Dielectric heating is the heating of an insulating
material by placing it in a high frequency electric field.
The heat results from internal losses during the rapid
reversal of polarization of molecules in the dielectric
material.
In the case of a person in an RF field, the body acts
as a dielectric, If the power in the RF field exceeds 10
milliwatts per centimeter, a person in that field will have
noticeable rise in body temperature. The eyes are
highly susceptible to dielectric heating. For this reason,
you should not look directly into devices radiating RF
energy. The vital organs of the body are also susceptible
to dielectric heating. For your own safety, you must not
stand directly in the path of RF radiating devices.
PRECAUTIONS WHEN WORKING ALOFT
Prior to going aloft, you must follow all NAVOSH
and local requirements such as wearing a harness and a
hard hat. You must have a safety observer and meet all
other requirements.
When radio or radar antennas are energized by
transmitters, you must not go aloft unless advance tests
show that little or no danger exists. A casualty can occur
from even a small spark drawn from a charged piece of
metal or rigging. Although the spark itself may be
harmless, the “surprise” may cause you to let go of the
antenna involuntarily, and you may fall. There is also a
shock hazard if nearby antennas are energized.
Rotating antennas also may cause you to fall when
your are working aloft. Motor safety switches
controlling the motion of rotating antennas must be
tagged and locked opened before you go aloft near such
antennas.
When working near a stack, you should draw and
wear the recommended oxygen breathing apparatus.
Among other toxic substances, stack gas contains
carbon monoxide. Carbon monoxide is too unstable to
build up to a high concentration in the open, but
prolonged exposure to even small quantities is
dangerous.
SUMMARY
Naval communications using satellite and various
antennas types must always be ready to shift from
peacetime to wartime requirements. To this end, the
diversity of fleet communication operations has given
the Navy an expanded capability to meet ever-
increasing command, control, and support
requirements by use of satellites and assorted antennas.
Additionally, this variety of communications
technology has increased the requirements for greater
proficiency from all operating personnel. As a
Radioman, you will be tasked with higher levels of
performance in an increasingly technical Navy.
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