Page 109 - International safety guide for oil tankers and terminals

GENERAL HAZARDS FOR SHIP AND TERMINAL

4.8.2.1 Medium and High Frequency Radio Transmissions
During medium and high frequency radio transmission (300 KHz-30 MHz),
significant energy is radiated which can, at distances extending to 500
metres from the transmitting antennae, induce an electrical potential in
unearthed ‘receivers’ (derricks, rigging, mast stays etc) that is capable of
4.8.2.2 VHF/UHF Equipment ย์ฝกพาณิชย์นาวี
producing an incendive spark. Transmissions can also cause arcing over
the surface of antenna insulators when they have a surface coating of
salt, dirt or water.

Therefore, it is recommended that:

All stays, derricks and fittings should be earthed. Bearings of booms
ship is alongside the berth.าเท่านั้น---
should be treated with electrically conductive grease (such as graphite
grease) to maintain electrical continuity or suitable bonding straps
installed.
Transmissions should not be permitted during periods when there is
likely to be a flammable gas in the region of the transmitting antennae
---ใช้เพื่อการศึกษ
or if the antenna comes within the shore hazardous zone.
Main transmitting antennae should be earthed or isolated whilst the

If it is necessary to operate the ship’s radio in port for servicing purposes,
there should be agreement between tanker and terminal on the
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procedures necessary to ensure safety. Among the precautions that might
be agreed are operating at low power or the use of a dummy antenna
load which will eliminate all radio transmissions to atmosphere. In any
งานห้องสมุด ศูน
case, a safe system of work must be agreed and implemented before
energising such equipment.

The use of permanently and correctly installed VHF and UHF equipment
during cargo or ballast handling operations is considered safe. However, it
is recommended that the transmission power be set to low power
(one watt or less) when used in port operations.

The use of portable VHF/UHF radios within a terminal or on board ship
presents no hazards as long as the equipment is certified and maintained
to intrinsically safe standards and the power output is one watt or less.

The use of VHF/UHF radio equipment as a means of communication
between ship and shore personnel should be encouraged.

4.8.2.3 Satellite Communications Equipment
This equipment normally operates at 1.6 GHz and the power levels
generated are not sufficient to present an ignition hazard. Satellite
communications equipment may be used therefore to transmit and
receive messages whilst the ship is in port.

4.8.3 Ship’s Radar Equipment

Marine radar systems operate in the high Radio Frequency (RF) and
microwave range. Radiation from the scanner fans out in an almost horizontal,
narrow beam as the scanner rotates. In port, it will pick up cranes, loading arm
gantries and other such structures, but it will not normally spread down to the
ship’s deck or jetty.

© ICS/OCIMF/IAPH 2006 75