(1)
Main steering gear is the machinery,
the steering gear power units, if any, and ancillary equipment and
the means of applying torque to the rudder stock (e.g. tiller or quadrant)
necessary for effecting movement of the rudder for the purpose of
steering the vessel under normal service conditions.
(2)
Auxiliary means of activating the rudder is
the equipment which is provided for effecting movement of the rudder
for the purpose of steering the vessel in the event of failure of
the main steering gear.
(3)
Steering gear power unit means
in the case of:
-
(a) electric steering gear, an electric motor
and its associated electrical equipment;
-
(b) electro-hydraulic steering gear, and electric
motor and its associated electrical equipment and connected pump;
and
-
(c) other hydraulic steering gear, a driving engine
and connected pump.
(4)
Maximum ahead service speed is
the greatest speed which the vessel is designed to maintain in service
at sea at its maximum permissible operating draught.
(5)
Maximum astern speed is the speed
which it is estimated the vessel can attain at the designed maximum
astern power at its maximum permissible operating draught.
(6)
Fuel oil unit is the equipment
used for the preparation of fuel oil for delivery to an oil-fired
boiler, or equipment used for the preparation of oil for delivery
to an internal combustion engine, and includes any oil pressure pumps,
filters and heaters dealing with oil at a pressure greater than 0.18
N/mm2.
(7)
Normal operational and habitable conditions means conditions under which the vessel as a whole, its machinery
services, means of main and auxiliary propulsion, steering gear and
associated equipment, aids to safe navigation and to limit the risks
of fire and flooding, internal and external means of communicating
and signalling, means of escape and winches for rescue boats, are
in proper working order and the minimum comfortable conditions of
habitability are satisfactory.
(8)
Dead ship condition is the condition
under which the main propulsion plant, boilers and auxiliaries are
not in operation due to the absence of power.
(9)
Main switchboard is a switchboard
directly supplied by the main source of electrical power and intended
to distribute electrical energy.
(10)
Periodically unattended machinery spaces means
those spaces containing main propulsion and associated machinery and
all sources of main electrical supply which are not at all times manned
under all operating conditions including manoeuvring.