18.4.1 Personnel should not
enter cargo tanks, hold spaces, void spaces, cargo handling spaces
or other enclosed spaces where gas may accumulate, unless:
-
.1 the gas content of the atmosphere in such space is
determined by means of fixed or portable equipment to ensure oxygen sufficiency
and the absence of toxic atmosphere; or
-
.2 personnel wear breathing apparatus and other
necessary protective equipment and the entire operation is under the close
supervision of a responsible officer.
18.4.2 Personnel entering
any space designated as gas-dangerous on a ship carrying flammable
products should not introduce any potential source of ignition into
the space unless it has been certified gas-free and is maintained
in that condition.
18.4.3.1 For internal insulation
tanks, special fire precautions should be taken in the event of hot
work carried out in the vicinity of the tanks. For this purpose, gas
absorbing and de-absorbing characteristics of the insulation material
should be taken into account.
18.4.3.2 For internal insulation
tanks, repairs should be carried out in accordance with the procedures
provided for in paragraph 4.4.7.6.