17.16.1 For the carriage
of ethylene oxide the requirements of 17.20 apply,
with the additions and modifications as given in this section.
17.16.2 Deck tanks should
not be used for the carriage of ethylene oxide.
17.16.3 Stainless steels
types 416 and 442 as well as cast iron should not be used in ethylene
oxide cargo containment and piping systems.
17.16.4 Before loading,
tanks should be thoroughly and effectively cleaned to remove all traces
of previous cargoes from tanks and associated pipework, except where
the immediate prior cargo has been ethylene oxide, propylene oxide
or mixtures of these products. Particular care should be taken in
the case of ammonia in tanks made of steel other than stainless steel.
17.16.5 Ethylene oxide should
be discharged only by deepwell pumps or inert gas displacement. The
arrangement of pumps should comply with 17.20.5.3.
17.16.6 thylene oxide should
be carried refrigerated only and maintained at temperatures of less
than 30°C.
17.16.7 Pressure relief
valves should be set at a pressure of not less than 5.5 bar gauge.
The maximum set pressure should be specially approved by the Administration.
17.16.8 The protective padding
of nitrogen gas as required by 17.20.15 should
be such that the nitrogen concentration in the vapour space of the
cargo tank will at no time be less than 45% by volume.
17.16.9 Before loading and
at all times when the cargo tank contains ethylene oxide liquid or
vapour, the cargo tank should be inerted with nitrogen.
17.16.10 The water spray
system required by paragraph 17.20.17 and
that required by 11.3 should operate
automatically in a fire involving the cargo containment system.
17.16.11 A jettisoning
arrangement should be provided to allow the emergency discharge of
ethylene oxide in the event of uncontrollable self-reaction.